In order to figure out where the hole for the caliper mount needs to be you need to measure at least one of those hole to the axle centerline.

I'd be interested to see where this goes and would be a buyer if an adapter was made (to allow use of an omega brake).

Three issues to consider:
1) Due to the location, the new (omega?) brake you end up using will be exposed to the wind (along with the new adapter). In other words, unlike the original brake, it will no longer be shrouded and the exposure to the wind will make it less aero.

2) Based on where the cable comes in, I don't see any way it could be anything other than center-pull.

3) The other quandary is the cable itself. Perhaps a hydraulic cable would be best, to avoid kinking. Magura RT6?

I wish you all the best in this and again, I would be a buyer if it was made with quality.

Agree, Maguras all the way.

---

ishi no ue ni san nen | Perseverance will win in the end. | Blog | @nebmot | Strava | Instagram |

You could look on Craigslist for someone local that has a 3D printer and can do the design for you to work out prototypes at a much cheaper than going to metal. A college student could probably do this for you pretty quickly.

---

ishi no ue ni san nen | Perseverance will win in the end. | Blog | @nebmot | Strava | Instagram |

If I place the caliper bolt right on the smaller, lower hole in the frame, the brake pads line up very well with the wheel.

---

Alex Arman

Strava

Good idea. I'll just hang around the CU campus trying to not look creepy :)
But really, that is a great thought. Will try to find someone to make some mock-ups.

I am running Maguras, for sure. And I am okay with the minor "exposed rear brake aero drag" to have drastically improved braking.

---

Alex Arman

Strava

That will make placing a through bolt in that location very difficult.

It would probably be easier to use a 'Direct Mount' interface since that is two threaded holes on either side of the central bolt hole.

That would knock the maguras out as a possibility though. Omegas, shimano DM brakes, and EE would still be possible though.

This is the adapter Orbea makes for the Ordu OMR to switch to direct mount brakes. The cabling is different also. Full housing from lever to brake, and also a new (larger) cover.

If that is the case, why are you not just finding the right spacer and bolt diameter to mount an Omega right into the frame there, forgetting about the other two mounting posts?

Honestly, I don't completely trust that the frame hole and threads can handle brake force.

The rocker pivot bolt that hole is designed for is spec'd only to 3nm of torque.

http://cervelo.co.kr/...efe6&ckattempt=1

---

Alex Arman

Strava

I think it should be alright. What do think handles the brake forces, or lack there of, now?

You need to measure where the braking track is in relation to the current mounting holes. An easy way would be to install the P4 brake and take a measurement at the mid point of the pads.

I found a brand new 2011 frame...planning on building it up this fall...I too would love to find another option for the brakes...hope someone figures this out...

Let me know if you find a CU student. My daughter was supposed to make me some parts, but so far she is "too busy". With all the tuition I pay you would think she could help dad out, ...but no.

I've planned to make basically this exact thing for quite some time, but never seem to get around to it. I've got a set of Maguras waiting for the project. The problem as I see it is that the adapter plate creates a long moment arm between the brake bosses and the attachment point for the adapted brake. The whole thing will want to accordion away from the frame under braking forces, so you've either got to rely on the unknown structural integrity of that 3rd hole, or make the adapter plate beefy enough that it won't flex too much. Determining the proper plate thickness is the crux of the design, and I haven't investigated it enough to figure out the forces it will see. A good baseline would be to consider the thickness of the existing cantilever arms, but account for a moment arm 2-3 times longer-- it gets to be a pretty thick plate unless you go with steel. I'm really surprised by how thin the Orbea adapter looks.

The original design is basically a center pull cantilever with really poor mechanical advantage. Thinking about it now, I wonder if you could fit a lowly linear pull V brake to the existing bosses. It might not work well with traditional aero brake levers, but worth some investigation.

Yeah, I'm all in using Maguras, so really want to figure out that design. You sound much smarter than me with an engineering mindset, so hopefully we are getting the right people on this thread to make this damned thing :)


Regarding a cantilever option, a Paul Motolite could work, since the arms are narrow and the springs are built into the boss bolts. Just not sure a TT brake would have enough cable pull.

https://paulcomp.com/...components/motolite/

---

Alex Arman

Strava

Maguras are MUCH harder than Omegas due to the fact that the post is threaded into the body rather than a bolt that goes through.

I have them on my Dimond, for which I figured out how to make such a thing work in a reasonable way, which was to put a very thin, very hard nut on the post.
Then screw the post (and brake) round and round and round until it's almost tight, and aligned correctly. Then unscrew the nut against the frame.

A similar thing could be done here. If I owned a P4 I would build them for you nerds, but I don't have a frame to work on.

I likely have access to a 3-d printer through colleagues. unfortunately, I have no idea how to create 3-d files for printing.

This was my first thought on reading the thread. I considered doing something similar for an FM087 Frame I had a few years ago, but I came to the same conclusion & figured that the 3rd hole (BB Cable Guide Hole on that Frame) wouldn't be worth the risk.

One solution might be to have longer "posts mounts" that "rib" into the main arch of the piece & avoid the 3rd hole altogether, but that would have to be analyzed (FEA).

I would think that a piece that adapts to the Direct-Mount standard would have less of that cantilever effect on the mounting points.

---

---

The brake forces (pad to rim) do not change depending on where the brake is mounted to the adaptor plate.

Any updates?

If someone can provide a dimensioned sketch, I'd be more than happy to provide a 3D file and/or print for you to check the design.

---

Strava

Awesome, thanks! A buddy of mine sketched up a design. What file format would work best you for 3D printer? I'll ask him to save it in that format.

---

Alex Arman

Strava

STL file for a 3d print. If you need the 3d done, a simple picture with dimensions will work.

---

Strava

Let me know if this DropBox attachment works. Else, PM me with you email, and I will forward it over.

https://www.dropbox.com/...0MOUNT%20AA.STL?dl=0

Thanks!

---

Alex Arman

Strava

Printing now.

---

Strava

You the man! PM when it's all done so we can chat shipping and your compensation.

---

Alex Arman

Strava

You *are* going to keep updating this thread, right?

---

Citizen of the world, former drunkard. Resident Traumatic Brain Injury advocate.

Lol, yes, for sure. Once I get the 3D piece, I will do some testing to confirm everything lines up nicely.

Then, the next step is to find a CNC shop to cut the final product out of alloy.

---

Alex Arman

Strava

/like

---

Citizen of the world, former drunkard. Resident Traumatic Brain Injury advocate.

/like x2

Out of curiosity which 3d printer are you using? I have a Prusa i3. Got it after building a Mars rover replica and fruitless attempts to find just the correct mounting hardware for the controller, battery, camera, solar charger, etc.... then realization set in: it'd be a piece of cake if I could make the pieces.

Keep me in the loop. Very interested!

For this I used a Flashforge Replicator. Its a clone of a Makerbot Replicator 1.

Anyway, parts printed. I'll upload a picture shortly.

---

Strava

Very excited. Count me in on buying one of these sunzabitches. Thanks

I may have missed something...is that top hole going to be clear to accommodate a centerpull brake like a tririg? And the two lower holes will be for mounting hardware only? Thanks

doublea was the one who designed it, so I'm not sure. My assumption was that yhere is supposed to be a 4th hole for mounting a brake caliper.

---

Strava

Hookay, wanted to share some updates. First off, huge thanks to gmh39 for printing the adapter. Really, very appreciate you're help.

The original idea was to just run 3 holes, with the upper hole lining up the brake caliper and the upper frame hole. It does line up very well, however, the tire/caliper clearance is extremely tight. But not too shabby for the 1st prototype.

Some photos below of the fitting.

[url=https://ibb.co/kk00Kb][/url]
[url=https://ibb.co/jDNrQG][/url]
[url=https://ibb.co/daDy5G][/url]
[url=https://ibb.co/fT3LKb][/url]
[url=https://ibb.co/gubkkG][/url]

---

Alex Arman

Strava

No problem. Let me know if you want to do another iteration.

---

Strava

Nice progress. In the first couple pics it looks like there is a machine screw thru the 3rd (top) hole, mounting the adapter to the frame. In the other photos it looks like the brake bolt goes thru that hole, so I assume the machine screw was removed and nothing is attaching the top of the arch to the frame once the brake is installed. Is this correct? Just want to make sure I understand the assembly.

Also, do you think there’s room for a 3D printed fairing over the whole thing?

I am very interested in either buying a finished article or having one made. The fact you've added a magura brake was the clincher for me.
Such a niche product but the rear braking on my p4 is woeful

Yes, that is correct. My original goal was to use the top hole for the brake caliper, but also have a smaller support bolt going into the frame. Although I could still make that work, the tire clearance is too tight for my liking.
Version 2.0 will have a 4th hole at the top exclusively for the caliper, with the original 3 holes bolting directly into the frame.

Yes, I think a full fairing could work. My plan, at the moment, is to dremel the current P4 fairing to fit around the brake caliper. This will cover the internal wires as well as the chain stays where the original brake arms are located. Then, I may get the rear P5 Magura cover and somehow hack that to fit over the brake and, again, somehow fuse with the P4 cover. Not super elegant but just the first thought in my head.

---

Alex Arman

Strava

Well done!


I’m assuming a tririg would fit there too right? I’m not familiar at all with maguras.

Yep, TriRig should work as well. I'll try to borrow one from someone once I get version 2.0 built out to confirm.

---

Alex Arman

Strava

Subscribed. looks like a needed mod.

---

BoulderCyclingCoach.com

You win. Count me in. I want one of those things!

TAKE MY MONEY!!!! lol

One question for you. How much clearance do you have now? Are you are able to put the same sized wheel as before? The P4 is tight. I don't want it to be any more narrow.

With this first interaction, tire clearance is certainly smaller. So I don't want that to happen.

Version 2.0 will spacer the caliper further away to have the same clearance as a stock P4.

---

Alex Arman

Strava

Good job sir!

Great stuff here. I am having all kinds of head ache with my (new to me) P4 and am hoping to piggyback off your project. Status update?

For you? No. You're too fast. You must live with crappy braking.


But really... took a bit time off for the holidays, but am working on version 2 with a CAD buddy of mine. Will redesign to increase tire clearance and better pad/brake track alignment.
I'll have the CAD file done this week and just need to get it off and 3D printed.

---

Alex Arman

Strava

This is great! I have a CNC and prototyping shop. Once you get it to a point, get in touch with me and I can give you a quote on getting it done out of aluminum and let me know if you need a hand with the design at all, although it looks like you have it under control :)

Cheers,
Omid

---

---------------------------
http://www.o-block.com/

Not to be a Debbie-downer here, but why on earth would I want to bolt that to the bottom of my P4? The P4 rear brake isn't the greatest thing ever, but it's passable, and more importantly is very clean aerodynamically. This thing, while it's a tremendous engineering exercise (it really is a nice bit of engineering) is aerodynamically hideously bad. I can't see why, on a tri bike, I'd want to make that trade-off for perhaps slightly better rear braking?

For me, I am very happy to have dramatically better braking for the cost of maybe a watt of drag savings.
I don't have data to back it up, but below bottom bracket drag must be such a small number compared to everything else. Hell, the Shiv with Magura brakes does the exact same thing I am. Hangs it down super low for the wind to hit.

---

Alex Arman

Strava

how do you know the aerodynamics of the magura vs. oem brake?

for reference, on a p5, the faired vs. unfaired rear magura made absolutely no difference. so, just curious how you arrive at that conclusion.

I suspect it makes almost no difference aerodynamically because the flow in that location is already detached and turbulent. Add in the planned cover and they're all set.

I don't, but I know that the OEM rear brake sits inside the cavity that this adapter bracket is sitting in, and is covered entirely by the fairing. With this setup, the rear brake sits entirely outside where the fairing would be, so in terms of aero cost it's not "OEM vs Magura" but rather "Magura vs. nothing" (if that makes sense).

Just curious - have you actually ridden it and confirmed dramatically better braking?

I have not. In fact, I have never ridden the P4 with stock brakes. But I have heard many people complain about its lack of power. Also, I have a friend who's P4 rear brake completely failed and ended with a crash. I do not wish to test for myself.

I have, however, used Magura brakes before on a loaned P5. And, my god, did I instantly fall in love. The confidence that I can lock up the wheel with a single finger really made things nice.

---

Alex Arman

Strava

From my understanding, it's less an issue of poor braking as it is an issue of the v-brake (both original and Evo) that are made for the P4 require constant adjustment to prevent from rubbing on the rim. This is an issue common to all v-brakes, but the narrow width of the P4 v-brake increases rubbing. So, I'm going to imagine that having brake rub nearly every pedal stroke is worth addressing.

I love the idea of having the adapter cnc'd. Further, I'd like to see a 3D printed cover that attaches to the cnc machined adapter, and fits the Tririg and Magura brakes.

Good luck, and great work. I look forward to seeing the final product.


now, to comment on braking: I've used DA, Red, Campy, EE rim brakes, and the Magura hydro-rim brakes are a dream to use - the ratio between lever movement and pad movement is perfect.

---

wovebike.com | Wove on instagram

This is exactly right. I bought my new 2011 P4 in Jan 2012. Enjoyed it for five years but was constantly having to adjust the rear brake / rubbing, etc. The rubbing issue cost me a podium more than once.The actual braking (lack of) I could live with. Only disc wheel that would fit was the original Zipp 900 because of the tight clearance. Last January, my LBS was doing it's annual tune and confirmed the brake couldn't be adjusted to prevent the occasional rubbing. Cervelo replaced with a 2014 P5 frame which I've ridden this past year. PITA to pack and ship but a superb bike and brakes work great. The P4 was a great bike....if you can get by just using the front brake. I don't know if I'd put a lot of time/money into this frame....just my opinion.

unless you're one of us folks who can't get low enough on a P5.

I'm on a Speedconcept and can't quite get low enough; the new P5x would probably do the trick, but the price.... so, this is where the P4 comes in nicely. It has amazing geometry.

---

wovebike.com | Wove on instagram

I'm moving from a 2009 P4 to Cervelo P2 with Magura brakes and can echo most of those sentiments about braking power. I used a Renn Disc and the aluminum braking surface was much better (provided adequate braking power) than a Zipp 900 that I tried.

However, adjusting the brakes for rub was never an issue for me(?). Just curious, but did you have an in-line barrel adjuster? I did, and perhaps that made all the difference to get the brake set up with the right clearance the first time.

Yes, had the barrel adjuster....and also used the Zipp 900 with the aluminum braking track. The problem was (and was getting worse over time), the "stud" that attached the brake assembly to the frame was held by epoxy and was starting to loosen and wobble, therefore one side of the brake would not release properly when the brake would be first applied. I never realized this and spent a lot of time shaving down the pads. The last few races I did with the bike, I only used the front brake. After the 2016 season, my LBS contacted Cervelo who confirmed this was a common issue and was not repairable (I was hoping it was.....loved the bike). The stack and reach was close enough on the P5 and I was able to duplicate my position.....no issues. I think the P5 bike is more stable and handles better and I've kept or improved my bike times while switching to a pair of Enve 8.9s. And the brakes required no adjusting this entire last season. That's why I said I wouldn't spend a lot of money fixing a P4 over maybe a used P5, and you would have more rear wheel choices.

I'll second this. I have a 2011 P4 that I absolutely love, however, that back brake makes everything so much more difficult. I couldn't figure out why everyone was passing me on the bike at Choo 70.3 in 2016 until I went to get my bike after the race and the back wheel wouldn't move. I'll gladly give up a watt or two if I can use a Tririg brake instead of that crap that's on the bike now which is not even remotely usable.

The P4 was before I really got into tri. Something I have been wondering..... I have seen many people refer to the p4 as a flop. Why? It has great geometry, so why was it a flop? Help me understand what I am missing.

---

blog

Well, I was selling Cervelo at the time. I liked it, but there were four things that I was hearing from customers and other shops that made it unattractive to buyers: the very skinny downtube, skinnier than the P3 and P3C, was deemed odd looking; the waterbottle was deemed non-functional and odd looking, especially with how the frame looks when the bottle is removed; and shops hated working on the rear brake, they hated how dirt collected inside the rear brake area, and tire/rim clearance was an issue. I saw shops not wanting to sell this bike.

---

wovebike.com | Wove on instagram

It's a flop because it didn't sell well. There are a lot of reasons for this, but basically that's why.

Most people don't ride long and low, or at least aren't fit long and low, so it's not great geometry for them. Think of the bike fits at your average tri, they'd be on a foot of spacers. Additionally the rear brake is difficult to set up and from the sound of things it is easily misaligned so it rubs while you ride.

Love how looks came before the crux of the issue. :D Damn I love slowtwitch. Yep the rim/tire clearance was a big problem. And that stupid rear brake design.

Well, if the looks are off then the customer will just bypass the bike for something else, so those other technical issues don't even come up.

---

Swimming Workout of the Day:

Favourite Swim Sets:

2020 National Masters Champion - M50-54 - 50m Butterfly

Alright guys, here's an update. Had a new prototype printed and it is better.
I dremeled open the stock brake cover to allow the Magura to fit partially inside. The cover still covers up the shift cabling and keeps things clean. (I think it's clean - people will bitch that it's not 100% faired)

Tire and rim clearance remains the same as the stock brake, so that's good news. Looking to print off 1 final design this week and ride it. Then can give more feedback and see the interest in producing more to the lovely ST crowd.

Btw, there is another forum member, notaero, who has claimed to have created a similar adapter for Magura brakes. However, he hasn't responded to any of my PMs or other members requests for photos. So keep bugging him :)

---

Alex Arman

Strava

That looks awesome! Well done. Magura brakes (or tririg) on a P4 could definitely breathe new life into that frame.

Hi, nice work.

I am working away from home/my bike, so I do not have access to take photos, and rarely have the time to look at this forum. My concept is similar, however there is more spacing between the bolt closest to the BB axis and the Magura. I use 4 holes total. I have the brake a little closer to the frame, and the brake blocks are nearer to the end of their adjustment range. The side effect is the tyre clearance is a little larger, but the width between chain stays is the real limitation there. I used 5083 aluminium plate.

One note, the crank set in the photos is missing the NDS arm retention bolt, i would not ride that without it.

Thanks, appreciate the info and your design. Just giving you some shit for no replies :)

I am going to try and space the brake a bit further away from the tire, and slide the brake shoes to the end of the caliper, like you mentioned. Currently, I am trying to figure out a way to mount the brake cover AFTER mounting the caliper and adapter. Right now, I have to mount them together - which isn't that big of a deal, just means the caliper has to be perfectly centered on the adapter at time of installation.

And yes, the crank bolt is missing, but it's just a pre-load bolt. No different than removing your stem top cap after properly torquing down your stem on the steerer.

---

Alex Arman

Strava

OT but, my caution comes from a singular experience seeing a Rotor 3D arm drop off the axle during a hill climb. The 500w - 0w crash resulted in the rider (who is a competent mechanic) laying on the wrong side of the road. We put it down to the arm working itself off the greased/antiseized spline. Secondary retention is nice.

Latest update: It's complete! The final version was 3D printed out of pretty thick plastic. It's sturdy, so not yet sure if it needs to be made from aluminum.

I have yet to ride it outside :/ But will put it to the test in a race this weekend. So if I don't die, I'll have more photos and details for everyone next week.

---

Alex Arman

Strava

I'll be interested... let us know how your testing goes!

Awesome. Good luck

Update?

---

http://www.clperformancetraining.com
http://www.pillasport.ca

My final version is done and installed. I have 1 race and 3 other training rides on it, and it has functioned perfectly.

I am printing out another copy to send to a friend who will install his TriRig. I will put together a little how to video, as well.

I personally feel the 3D plastic design is strong enough to work. I do not think think the aluminum version is needed. But certainly willing to hear other people’s opinion on that.

---

Alex Arman

Strava

Can I buy two from you?

My gut says don’t use the printed plastic. Even if it’s strong enough initially, its fatigue and aging properties are relatively unknown and probably poor. The consequences of a brake ripping off are pretty high, so let’s not do that!

Could you make a video/picture for us: on a trainer, lock up the rear brake and stand on the forward pedal. Cycle your weight on and off a few times while videoing the brake adapter from the side to see if/how much it flexes away from the frame. It might not be a lot, so lighting and optics might be tricky, but worth a shot.

Thanks for your work on this project. It’s something I’ve wanted to do for a while, but never find the time.

Printing off a few more now and should have them later this week.
I’m looking at $50 shipped each.

---

Alex Arman

Strava

I’ll try to get a video up this week. We’ll see how much flex my 145 pound self can create.

---

Alex Arman

Strava

What are you printing them out of?

I have recently been printing aerobar risers out of ColorFabb XT-CF20. It's an incredible product.

More here:
https://www.3dhubs.com/talk/thread/thoughts-about-new-carbon-fiber-filament-colorfabb


The structural capabilities surpass any of the other carbon infused filament I have used/seen except the MarkForged direct injector.

PM me and I'll send you payment. You don't know how excited I am if this works and I can replace that useless brake.

How long have you been using the risers for? This could be the material I need for some angled risers for my aerobars.

---

Strava

ABS plastic, because that’s what the 3D printer I have access to uses.

I’m all for making stronger and better versions. I’m just here to get the ball rolling. You definitely know way more from a technical aspect than I do.

---

Alex Arman

Strava

Maybe 200 miles? I printed them with 100% infill, other than where the bolts go through (on Ventus II bars). They are indestructible (but also only 30mm)

What brakes are you going to use?

Strongly disagree!!! At least it’s just a rear brake.

Alex,

Any update on the back brake?

Hey, sorry for the delayed response on this thread. Have been swamped with year end approaching at work.

I have a handful printed out and available for sale.

Shoot me a PM and we can coordinate payment and shipping.

---

Alex Arman

Strava

I've got Kiley's P4 at my shop, and started tinkering with the BB area.

It does not appear sensible to try to mount the brake directly to the frame as I had intended. The space there simply is not large enough to make it work.

New plan is to utilize a 8mm thick chunk of carbon to build the U shape, mounting to the 3 existing bolts. Then bolt the Tririg direct-mount adapter to the carbon plate, so as to spread the load to all 3 mount bolts, rather than focusing all of the brake vs. wheel torque on the front one. Honestly that mount point is probably plenty strong, but why not add the ability to have a direct mount there?

So are you using the Omega SV to mount directly to your u-shaped plate? Or is your u-shaped plate going to have the 2 direct mount holes? Thereinby using the u-shaped plate, the TriRig direct mount adapter, then the Omega X brake?

---

Alex Arman

Strava

U shaped plate will have the 3 holes to mount to the Cervelo inserts, plus 2 direct mount holes with flanged rivet nuts inserted.

Like this:


That will leave ~9mm of good threads for the Tririg adapter plate to bolt into when using an Alpha X, and Kiley will have several options including Magura RT's or Shimano direct mount if he wants to swap out brakes later. That said, the Tririg is probably the most aero option here, and doesn't seem to have a down side.

Smart. I like your style.

But just make sure Kiley knows that he will only have the 2nd coolest P4 on the interwebs.

---

Alex Arman

Strava

I'm doing this work because I find it interesting, and carbon fiber owns my soul.

But IMO Kiley should buy a size 48 P5 for cheap and throw the P4 away. Its a great flat land TT machine, but the P5 is better in every way once you throw out the Aduro bars.

The issue for Kiley has always been about getting low enough, but since the P5 in 48cm is the same stack/reach as a small Omni, I dont see a reason to continue down this path. At least not with these frames approaching $2000, brand new.

I've received Alex' widget and ordered an Omega, which should be here in a week or so. If it fits (i.e if the bracket is wide enough for a DM adapter), I'm going to rip of your idea and drill some holes for rivets like that.

OT but I uninstalled my OEM brakes, and omigod I don't understand how I rode with those for so long. That's a singularly piece of bad engineering; in software we call shit like that 'premature optimization': you optimize shit you think is going to be slow, come up with design that doesn't really fit the rest of the system, and then in the end it turns out your major bottlenecks were somewhere else to begin with. But now you're stuck with an ugly wart on your design.

Besides badly engineered the brake was also rusted out, but that's on me for not properly cleaning the BB area. My excuse is that the fairing makes it 'out of sight is out of mind', and also that the fairing collects all matter of crap dripping down the frame (sweat, gatorade).

---

Citizen of the world, former drunkard. Resident Traumatic Brain Injury advocate.

Hey guys! Any updates on use/abuse of the adapters? I'm building up a new-to-me P4 and am not happy with the OEM brakes, very interested in how these are working for you all.

I’ve had great use of mine so far, no issues. Used it with aluminum and carbon wheels, both worked great.
Have descended some steep climbs, and again, no issues.

I have mounted and un-mounted my brake many times and see no signs of wear.

---

Alex Arman

Strava

what brake are you using?

Magura RT. But I have a buddy of mine on an Omega X with the adapter.

---

Alex Arman

Strava

doublea334 send me an adapter. I'm waiting for a shipment from tririg, which has bounced from Boulder to LA to NY and now hopefully to Canada over the last two weeks :-/ Once I have the brake, I'm going to attempt to mount it.

I'm all in; I took my stock brake off and it basically disintegrated between my fingers in a pile of corrosion and dust. Don't think I can get it back together.

---

Citizen of the world, former drunkard. Resident Traumatic Brain Injury advocate.

I have Kiley's finished with the 8mm carbon plate.

The first iteration with a 5mm carbon plate was OK, but IMO, not completely indestructible. Not willing to risk someone else's safety on hopes and dreams.

So, I got ahold of a thicker chunk that my dad has been hoarding for years and rebuild with a few mm more thickness everywhere and additional meat elsewhere. By utilizing the Alpha X adapter plate in just the right location, you change the way that the forces are distributed and how the deflection in the plate turns into a twisting force rather than a direct assault on the original upper bolt. I'm really happy with the design.

I also adjusted the location so that a Shimano direct mount would work with the same mount, but it's just not setup optimally for that with 25mm rims. 23mm was fine with an Ultegra direct mount. I suspect that I would have to move the NDS mounting stud about 2mm off center to make that brake work perfectly. It's certainly possible if someone wanted that.

Can you post some various pictures please

Happy to email them, but dont want to deal with scaling and uploading and hosting them. Have a newborn in my lap.
PM me.

I finally received my tririg brakes after USPS gave them a 2-week tour of the US - Boulder, Denver, LA, Brooklyn, then Toronto.

I did some playing around yesterday night:



I used some M4 bolts I had laying around - I need to get some longer ones with bigger heads. I have no concerns for the integrity of the adapter and the way it connects to the bike, but I will report back after I have actually ridden the thing.

Disadvantage of the tririg brake is that I will have to take the crank off to adjust the brakepads, but such is life I guess.

---

Citizen of the world, former drunkard. Resident Traumatic Brain Injury advocate.

We are currently doing the same thing at my bike shop. Can't wait until I have a true back brake. I'll feel so much more confident on the course.

Now i'm pissed that I got rid of mine. Balls.

---

"the trick is to keep losing weight until your friends and family ask you if you've been sick. then you know you're within 10 pounds. if they start whispering to each other, wondering if you've got cancer or aids, you're within 5. when they actually do an intervention, you're at race weight." - Slowman

How do we order the mount and adapter with instructions? I'm handy with a bike but can't custom make parts.

Are you mounting without the upper bolt that goes into the frame? Drilling later?

Driling later. First want to see how everything fits together.

---

Citizen of the world, former drunkard. Resident Traumatic Brain Injury advocate.

I think I'm done for now. I forgot to take pictures, but here is what I did since my previous post:
- longer screws.
- drilled a hole for the center bolt. Countersunk the bolt so it won't interfere with the brake.
- Dremeled the fairing. There wasn't a whole lot left over, but electrical- and duct tape do wonders.

Notes:
- I probably have to tape the fairing again. My aim is to reduce dirt- and water ingress as much or more as to decrease drag.
- I have a hard time finding socket head (I think that's what they're called) metric bolts. I used hex head ones from Home Depot which I'm afraid are going to rust out pretty quickly.
- The cable pokes out of the brake quite awkwardly. This is kinda annoying with the type of stand I have, but oh well.
- I'm going to have to wait and see if swapping wheels requires a lot of brake adjustment. If I can't find a 'one size fits all' setting the removing of the crank may become annoying.
- I wonder if I should keep the brake cover on. I'm afraid I'm going to lose it (it's only held by two magnets). I may tape it and turn that bottom bracket area into a giant tape ball.

---

Citizen of the world, former drunkard. Resident Traumatic Brain Injury advocate.

Silicone caulk?

Are they stainless steel? The home Depot stainless bolts are high quality and you'll be fine. They zinc bolts are ok but you'll see some surface rust.

Consider an inline barrel adjuster?

Probably not. I dremeled away large amounts of the center so the brake cable can pop out and into the brake. Not a biggie, even if I have to tape the thing every couple of months.



There was only one type on hand, and I *think* it's zinc, but not sure. But I'm going to take 15 minutes out of my busy day (ha!) and find some better screws. They probably have to ship from Outer Waziristan with a minimum order of 2 gross, but oh well.


[/quote]
maybe I'm shellshocked by the old brake, but I used to have to line up the brake pads with the rim for different rims. But maybe I don't have to do that anymore.

And I forgot to mention that I have awesome braking now. So main goal achieved!

---

Citizen of the world, former drunkard. Resident Traumatic Brain Injury advocate.

Stainless are shiny and black are zinc. If it's a hard to find size, just get it from McMaster. They ship same day.


Edit: it occurs to me that black screws may be oxide, but anyway just order stainless from McMaster.

what did you use to mount tririg to adapter plate?

I used the hardware that came with the brake. I stacked two of the serrated washers together and used one of the provided bolts and the recessed nut (which fit the hole doublea334 put in the plate). Disadvantage is that you can't easily take the brake off without taking the adapter plate off. But that's minor.

I'm going to take it apart again one of these days and then I'll post more photos.

---

Citizen of the world, former drunkard. Resident Traumatic Brain Injury advocate.

As promised I took the whole thing apart again. I located proper stainless M5 bolts (I needed one M5x25mm, 2x M5x30mm, 2x M5 nut, and some washers, plus stuff that comes with the TriRig Omega X). I also drilled a hole lining up with the P4's center bolt hole.

Here's a photo album outlining the process:

https://photos.app.goo.gl/xHAk2U0VYQJuC1Yr2

Remarks:

• I found out that I can actually adjust the brake with the crank in place. It's finicky, but it can be done.
• I taped up the fairing (especially the long slot accommodating the brake cable) with klassy black duct tape (the same tape you use to tape your water bottle closed with after you cut it open and put your flat kit in). This to prevent water and grit ingress.

---

Citizen of the world, former drunkard. Resident Traumatic Brain Injury advocate.

Thanks for the update

Great to hear! Do you have any on hand, or plans to print some more?

Yes, have a few more available that I can ship out this week.

---

Alex Arman

Strava

Just wanted to say I am a happy camper. I finally got out on Sunday to test the new back brake and it works better than I ever imagined. I can also now run a wider wheel than with the old brake. Thank you so much for doing this. I got one picture to upload.

Can you make a higher res picture available (email is in my profile)? Maybe I can learn something from the way you installed the TriRig.

---

Citizen of the world, former drunkard. Resident Traumatic Brain Injury advocate.

on the way.

Thanks dude.

---

Citizen of the world, former drunkard. Resident Traumatic Brain Injury advocate.

Can I get a plate? Thanks

Are there any differences between the 09 and 11? Rear brake or anything else.

I understand there are minor changes to the brake, so minor that it's still finicky and doesn't stop well, and changes preventing the seat stays from snapping. I think doublea334 answered a question from me about that as well; don't know if it was here or on another thread.

But I understand you should get a 2011 if you don't want your seat stays to snap.

---

Citizen of the world, former drunkard. Resident Traumatic Brain Injury advocate.

Hi guys, I’ve been receiving messages to reply, sorry I’ve been very busy with work.
I’m using a direct mount Magura mounted with a bracket that picks up on the original mount points.
My first prototype was abs, then a ti part. After a fatigue analysis I settled on a lighter aluminum part. This should be in the infinite fatigue zone for a 100kg bike rider system.
Still retains the PIA brake pad bolt obscured by the chain ring!

I hit the photo limit on the last post.

I'm curious if you guys have had any failures on the plastic parts yet? how are they holding up just after the mounting bolt area?

Now that is the right way to do it ,aluminum !

Who made that?

I installed a plastic one for someone and it will flex under load.
And if you over tighten it will start to crush

Hi, I designed it. The M7 bolts with the correct shoulder length were the most difficult thing to procure in this project.

So you replaced the 2 stock bolts on the caliper with linger, through bolts?

And how did you remove the stock, center mounting bolt? Doesn’t that pass through the reservoir?

---

Alex Arman

Strava

Hi Alex,

The exposed stud was removed (cut-off) only. I was careful about heat build up and did this with fluid in the bore.
The pivot bolts were replaced with through bolts. The magura threaded section was drilled out and obviously the front/back had to be spot faced. I used Ti bolts to save some weight and prevent any galling on the AL part.

Damn. That is one hell of a mod. Looks like a lot of work, but the end result seems fantastic.

Well done.

---

Alex Arman

Strava

Is the metal available to buy? If so how much?

Took a couple months to finally get around to the chop and swap, but happy with the vastly improved braking after installing today! No perceivable flex with the rear locked up while bouncing on the cranks (probably helps being skinny and 5'8"), and managed to install over/around the fairing with minimal dremeling to keep the grime away from the brake. Will update down the road if there are any issues.

Very clean!

---

Alex Arman

Strava

What mount did you use for the Tririg ?

Nicely done.

You did a better job with the fairing then I did. :-D

---

Citizen of the world, former drunkard. Resident Traumatic Brain Injury advocate.

I'm curious..I think what you guys have done is awesome...can it also be done, or has anyone discussed about it being done on a Felt DA? I hate the rear break.

Totally doable: https://forum.slowtwitch.com/..._install_P4455155-2/

---

Alex Arman

Strava

would you be willing to come up with one for me? Would love to put an Tri rig on the back

You’d have to reach out to the poster on that thread. I don’t have an IA to measure, fit, and test.

---

Alex Arman

Strava

will do..thanks

He doesn't want to sell or make any for others:( I understand why..but bummer

Is there anyone who has replaced their Evo rear brake that would be willing to sell me their old parts? New to the P4 family and hoping to keep it as original as possible whilst retaining the best possible functionality.

Yeah, I can sell you mine - everything but the fairing cover.

---

Alex Arman

Strava

PM'd

Alex,

Did you get my message?

Dan

I still need one of these, if I can't buy one is it possible to get the specs on the one that finally worked for the omega?

---

Ironman Certified Coach

Currently accepting limited number of new athletes

I found out, a year after the fact, that I somehow shared the wrong link. I edited my post above, and the link a couple of lines above this should be the right one as well.

---

Citizen of the world, former drunkard. Resident Traumatic Brain Injury advocate.

Once I get this installed, I am going to get one of my engineering students to 3D print a new fairing. This is awesome. I love my p4. There still really isnt another bike that fits short dudes that steep with full sized wheels.

---

Ironman Certified Coach

Currently accepting limited number of new athletes

Do you have any more of these plates available for sale?

Yes’r Sent you a PM

---

Alex Arman

Strava

So I got a CNC copy made out of aluminum
I used the 3D one but it would flex with the two point mounting
With the aluminum there is three point mounting super solid.
It’s a 1/2”thick can go down to 3/8”
Next step the fairing back on

That's way cleaner than mine!

---

Citizen of the world, former drunkard. Resident Traumatic Brain Injury advocate.

Late to the club but the rear brake adapter that came with my P4 (bought secondhand) snapped. I really love my fit on this bike and don't want to start over.

Does anyone have:
A) an adapter that I would be able to buy?
or
B) an original rear brake that I could install on mine to make it rideable?

Thanks in advance.

Contact > https://www.alden-carbon.com/
He made two versions out of aluminum for me
The second version Is a little thinner and shaped
It will work with Magura and tri rig brake
Pretty sure he has the file for a CNC

[/quote] Contact > https://www.alden-carbon.com/
He made two versions out of aluminum for me
The second version Is a little thinner and shaped
It will work with Magura and tri rig brake
Pretty sure he has the file for a CNC[/quote]
Resurrecting this one:

Tried to reach out to Glen, but site appears to be down as well as email. Does anybody have a resource for the plate. I can also work with the STEP file. Trying to save some SolidWorks effort;) and machining cost.

Cheers!

Anyone know how to Get hold of one of these adapters now?

I have a P4 that I just retired last year. All parts are original, brake, cover, everything. What is it specifically you are looking for?

The rear brake adapter wich is discussed in this thread