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Re: Official Speed Concept Owners Thread [Carl] [ In reply to ]
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I suppose I need to find a dealer with some experience with this. Unfortunately, I am not able to consider a warranty as I bought the bike used. I was looking online and saw a youtube video on the BB90 replacement. I had to giggle when I saw the guy get out the bearing removal and installation tool. Mine will be out as the crankset is removed.

I will find a good kit and try the loctite I guess. I appreciate your quick and complete responses, although I would try to talk you into a threaded BB design in the next generation.
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Re: Official Speed Concept Owners Thread [Carl] [ In reply to ]
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Bought the new 7.5 SC (light gray). Planning to buy the Draft Box II, but want the color to match. Is it possible to get the draft box custom painted by Trek?

http://endurancesportlifestyle.blogspot.com
Last edited by: TRIspud: Dec 1, 16 9:28
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Re: Official Speed Concept Owners Thread [TRIspud] [ In reply to ]
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Hi TRIspud-

It's something we've done for some of our Race Shop sponsored athletes, but generally speaking, no....at least not direct from Trek. A custom paint shop might be willing to take a shot at color-matching to the frame.



Carl Matson
Trek Bicycles
Design Engineer - Speed
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Re: Official Speed Concept Owners Thread [Carl] [ In reply to ]
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Thanks Carl. I'll check out the custom paint option.

http://endurancesportlifestyle.blogspot.com
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Re: Official Speed Concept Owners Thread [flocrest] [ In reply to ]
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I wanted to follow up with my bearing issue in case someone else was having the same issue (using GXP in a BB90 frame).

There are two parts to this,

1. Took the bike to an experienced dealer. He said the frame was nowhere near close to needing the V2 (slightly bigger) bearing. The bearing in question was loose, but it had failed and that could have been part of the fit problem. It was rusty and nasty with around 500 miles. The other bearing was fine. He said that the new Trek kit had some safeguards against the creaking, he said they started making them with a coating on the outside of the bearing to deal with some possible issues. Really, the bottom line with this is it was not installed correctly when I had the GXP kit put in. In fairness to the original dealer, it is possible that the install was messed up by me, as I did change the chainrings at some point and could have messed it up myself.

2. This is a bit more interesting and I wanted to see if Carl had any thoughts. While trying to find a fix for this, one of the bearing companies sent me correspondence comparing radial vs. angular bearings. I found it interesting and I thought others could benefit from me posting it.

The problem with using radial bearings in a GXP bottom bracket, particularly on a BB90 frame, is that SRAM expects one bearing (drive side) to be “free floating.” Normally, this means the bearing has free spindle on either side of it. This may work with fixed cups, but in a BB90 application, this would allow the bearing to back out of the socket or for the entire crankset to even shift toward one side or the other—hence the necessity of a wave washer to take up that excess spindle space and exert enough force to retain the bearing. This wave washer is necessarily going to put some side loading on the bearing. So, if you are with me, a radial bearing paired with a wave washer that gets compressed, means the radial bearing will be side-loaded, which is bad for the bearing. In other words, it’s a stupid factory design from SRAM. Angular contact bearings can correct this.

Since they are designed for side-loading, angular contact bearing work very well with the wave washer. Regardless of socket fit, I think an angular contact bearing setup is going to quieter because the crankset will be imparting inward force against the outer surfaces of the bearings. This should increase the friction fit inside the sockets. Additionally, I previously recommended the Teflon tape. If you want the bearings to fit tighter, this is a good method. It’s also somewhat “adjustable” due to the fact you can control the number of wraps around the bearing.

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Re: Official Speed Concept Owners Thread [flocrest] [ In reply to ]
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Glad to hear the V2 bearing wasn't necessary. Suspect what the dealer meant by a "coating" on current bearings is actually an integrated plastic seal, which also functions as a spacer much like the old orange seals (and silver cap on older SRAM BBs).

Lest anyone get the wrong idea about your "fixed cup systems" reference, the distance between BB90 bearing cups is also fixed...there's just a different set of seals and /or spacers involved to take up the slack depending on what BB your crank requires. This is not unique to BB90 either. Which brings us to the wave washer...

In a quick search through the forum plus some googling it seems the wave washer should be treated as an "optional" item...or, more accurately, as an "if needed" item. Whether as-designed or due to tolerance stackups between frame, bearing, and crank manufacturers, you'll have situations where the wave washer is not only unnecessary, but actually could contribute to the very problem you note re: axial loading on a radial contact bearing. Several SC owners (and, notably, some other brand owners as well) have found that their GXP-based crank & BB combo has no axial play after everything is torqued to spec...without the wave washer installed. Most often, this is discovered after an installation including the wave washer where the cranks seem unreasonably draggy.

The above certainly jives with my experience installing GXP-based cranks into my various BB90 bikes over the last few years...I don't think I've needed a wave washer in any of them.

Side note: GXP crank install torque is substantial. I've sometimes referred to "getting my gorilla on" when installing them, so it's possible people (particularly if they don't use a torque wrench) could put a wave washer in there and only get things tight enough to where the cranks seem to spin freely without lateral play but in reality they've got a loose crank that is going to gradually walk around and make noise, damage the bearings, etc.


Good tip on the teflon tape. For a bunch of other really good BB install tips - for all standards - all in one place check this out: http://www.vcrcbike.com/...bfiles/bbinstall.pdf . While it was compiled by an aftermarket bearing supplier and includes some info specific to their products, I found there was a lot of best practices info and other neat tips in there...like the tubular glue version of your teflon tape trick :-)

Cheers!



Carl Matson
Trek Bicycles
Design Engineer - Speed
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Re: Official Speed Concept Owners Thread [Carl] [ In reply to ]
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Silly question but are generation 1 and 2 stems innerchangable?
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Re: Official Speed Concept Owners Thread [pokey] [ In reply to ]
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I'm afraid not.



Carl Matson
Trek Bicycles
Design Engineer - Speed
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Re: Official Speed Concept Owners Thread [Carl] [ In reply to ]
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Thanks Carlnfor that detailed response on the wave washer. Using a gxp crank in my SC, I found the wave washer definitely added a lot of drag and even without it, there is no play.
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Re: Official Speed Concept Owners Thread [wsrobert] [ In reply to ]
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Does anyone have experience with running Hawk Racing bb bearings in a speed concept 7 series? I contacted them and they didn't really seem to know which bearings would fit (if any).

Any thoughts on the pros and cons of going this direction appreciated too.

Thanks,

Steve

Edit - running shImano cranks
Last edited by: Blue_Quest: Jan 8, 17 6:31
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Re: Official Speed Concept Owners Thread [Carl] [ In reply to ]
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With full weight on my elbows in aero, there is a clicking noise coming from the pads or aero bars. Not sure where, but if I lift my weight off my elbows, ever so slightly, the clicking stops. Any ideas? Doesn't sound critical, just annoying for 4+ hours.
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Re: Official Speed Concept Owners Thread [jareed58] [ In reply to ]
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hard to say without having the bike in front of me to try a few things, but my first reaction is it might actually be coming from the stem area?

for gen1 SC

for gen2 SC



Carl Matson
Trek Bicycles
Design Engineer - Speed
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Re: Official Speed Concept Owners Thread [Carl] [ In reply to ]
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First weekend out on the new-to-me Gen 1 SC. Thanks Carl for all the pestering re: fit and sizing and thanks to all the folks at Trek for this brilliant bike. "Stupid fast" doesn't even begin to describe it.



ZONE3 - We Last Longer
Last edited by: tessar: Jan 10, 17 0:07
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Re: Official Speed Concept Owners Thread [tessar] [ In reply to ]
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My pleasure. Looking fast there!



Carl Matson
Trek Bicycles
Design Engineer - Speed
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Re: Official Speed Concept Owners Thread [Carl] [ In reply to ]
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Carl, do you know if the mono extension plug-in version is still available? Or know where we can find them?
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Re: Official Speed Concept Owners Thread [iamAERO] [ In reply to ]
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Out of stock at the moment and unfortunately no information on when it'll come back in...but what I'm hearing is that it's still part of the existing options.

So, if you're looking for one and can't find it in stock at a dealer (unlikely, but not impossible) or in the classifieds, your dealer can certainly backorder one and that'll put you closer to the front of the line when they do come back in stock.



Carl Matson
Trek Bicycles
Design Engineer - Speed
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Re: Official Speed Concept Owners Thread [Carl] [ In reply to ]
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Great to hear! Thank you
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Re: Official Speed Concept Owners Thread [Carl] [ In reply to ]
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Carl,

I'm a happy owner of a 2014 speed concept 7 series. unfortunaley I missed the spacing issue on the pioneer power meter before ordering. The bike shop I went to (not my normal shop as i'm living and training out of the country) placed two small spacer rings on my left crank arm to give it 1-2mm of clearance).

What issues if any do you see with this set up in terms of the spacers themselves or flex causing contact with such minimal clearance?

Thanks.
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Re: Official Speed Concept Owners Thread [LecTriTFN] [ In reply to ]
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Glad to have you aboard!

Can't speak to that setup with the spacers, as our official stance is that the Pioneer system isn't compatible with our bike. That said, it's a workaround I've heard of before. In your place, if I wasn't willing to get a different power meter, I'd keep an eye on how secure my crankarm is...check it for any looseness every so often.



Carl Matson
Trek Bicycles
Design Engineer - Speed
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Re: Official Speed Concept Owners Thread [Carl] [ In reply to ]
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Ok, thank you for the quick reply, still debating if it's worth the trouble or if it's possible to return to Pioneer.

Im the meantime I'll keep an eye on it.
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Re: Official Speed Concept Owners Thread [Carl] [ In reply to ]
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Hi Carl,
I went from a size XL first gen 9 series to a size large gen 2. I was riding the first gen with low/far stem and the smallest spacer. I wanted to get lower so I got a size smaller frame. I have the low /far stem for the gen 2, and I have yet to build it. I'd like to be about an inch lower, what mono spacer do you recommend as a starting point?
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Re: Official Speed Concept Owners Thread [ridenfish39] [ In reply to ]
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Howdy!

The difference you're shooting for is about the same as the difference between frame sizes...so start with the lowest monospacer. Cheers!



Carl Matson
Trek Bicycles
Design Engineer - Speed
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