On a P4? The brake is hidden. Why would you want to consider? I have it on the front but wouldn't even consider for the rear.

The p4 rear brake lacks power and makes me nervous on rainy decents.

I'm just trying to improve braking and figured that even uncovered the omega x shouldn't be much of a difference aerodynamically.

Well, rainy descents make me nervous regardless. I bought mine new (2011 model) and over the years have been able to figure out how to adjust to maximize capability.....new pads.....make sure the adjustment screw is tightened down. Frankly, using the front brake mostly and optimizing the rear capability, I've never had an issue. How long have you had the bike.....relatively new and trying to get used to it?

That is a worthy quest. The P4 uses a cantilever brake with the pivot below the brake pads, and those often have crappy leverage and performance. One option could be a brake lever with a stronger pull ratio, like the Shimano TT-78 levers. That would not fully solve the problem, but it might help.

I've thought about this as a fun project bike.

Have a machine shop create a super stiff/strong horseshoe shaped chunk of metal, like a cantilever brake booster.
Thread it into the P4 existing brake threads where the stock brake bolts into the frame.
Then, have a short bolt/nut on the Omega brake to bolt into the top of the "horseshoe".

Tough to explain the idea in my head, but Google image "cantilever brake boost" and you should get a good idea of what I'm talking about.

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Alex Arman

Strava

Thanks! That's exactly what I had in mind! I wonder if anyone has done that?

Do you think this would work?

http://www.tririg.com/...60/000_Store_315.jpg

 Not that one specially, but that design would work.
That piece bridges either direct mount spacing or dual post spacing to work for the single brake bolt design of the Omega.

I haven't seen one in person, just photos online, but I believe the P4 rear brake spacing is unique. Your best bet is to the bring the bike to a machine shop, have them measure the brake spacing, then show them a picture of that Omega bridge piece as the end design.

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Alex Arman

Strava

I'm curious what kind of rear wheel you're using. I can lock up the rear brake on my P4, so I've never seen it as a problem. But that's on aluminum rims...

I've never ridden a P4. Just have heard lots of complaints about the rear brake.

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Alex Arman

Strava

It's the first generation P4 (I think maybe the rear brake design was improved on the newer P4 models).

I can also lock it up but the modulation is very difficult and it's difficult to adjust precisely.

I've used a number of narrow wheels, some aluminum and some carbon.

For all of these reasons, I just think the Omega X would be an upgrade. If anyone disagrees (or has personal experience that would lead them to think otherwise) please let me know. I'd love to hear about it.

Sounds like a fun project! A few (maybe more than a few) years ago a fellow was racing on a P3sl he'd fabricated a rear brake behind the bb for (can't find a picture unfortunately) of course metal not carbon but still... Shouldn't be too tough to fabricate something that would work fine, just be careful of clearance issues.

I think Alex's line of thinking would likely work best.

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My Blog - http://leegoocrap.blogspot.com

I don't necessarily disagree, but I'll give you a quick overview with mine (also a 2009 P4). I have very narrow rims on both my day-to-day and race wheels -- a Zipp 900 clincher. The brake wouldn't adjust enough until I added a washer on the fixed side to reduce the spacing a bit. It was good after that. Also added a barrel adjuster inline on the brake cable.

I know what you're saying about the modulation but it's also the rear brake, so I don't think about it as much. I've ridden that bike in a lot of hilly races and crappy conditions like Mont Tremblant last year :)

If you tear it apart and do this project I'll be interested to hear your results.