Carbon dropouts, slipping under pressure-New bike
So I recently bought a new frame, a hong fu fm011, built it up last night and went for a test ride today. I've had a set of carbon tubs for 2-3 months and was relatively happy with them, they did flex a bit but it was manageable(they need more tension, sapim cx-ray spoke are rated at 18max on Park-tool tensiometer while they are only done up at 15-16max.)
So I went to test the new-built bike and whenever I sprinted the wheel touched the brake pads by quite a quite often. I'm a heavy guy and relatively good sprinter(84kg, 1600watts max power) but I had ridden the wheels on a alu frame before and they weren't as bad as today. I tried a standing start on a small hill and the rear wheel pulled out of the carbon dropouts completely. I re tightened it a bit harder next time and went to ride again. Next tries it only moved slightly in the dropout, without coming out completely contributing to brake rub(maybe even frame rub) again as misalignment of wheel towards pads.
Thus after repeating the test several times I was pretty sure that the wheel slips slightly inside the carbon dropout when massive torque is applied although vertical dropouts.
The QR isn't massively serrated, but it's not too bad(it was from a giant wheelset), the hub itself is relatively serrated.
I'm gonna test out a shimano ultegra QR and also thought of maybe putting some carbon paste on the dropouts, I'm also gonna tension the driveside spoke to max tension rating and the non drive to whatever keeps the wheel centered. What else would you guys suggest? Anyone else had problems with carbon dropouts?
I know I will most probably not get to use my max torque during racing as great power generated in a sprint doesn't require so much torque, but when accelerating it's definitely a problem, so I need a solution.
So I went to test the new-built bike and whenever I sprinted the wheel touched the brake pads by quite a quite often. I'm a heavy guy and relatively good sprinter(84kg, 1600watts max power) but I had ridden the wheels on a alu frame before and they weren't as bad as today. I tried a standing start on a small hill and the rear wheel pulled out of the carbon dropouts completely. I re tightened it a bit harder next time and went to ride again. Next tries it only moved slightly in the dropout, without coming out completely contributing to brake rub(maybe even frame rub) again as misalignment of wheel towards pads.
Thus after repeating the test several times I was pretty sure that the wheel slips slightly inside the carbon dropout when massive torque is applied although vertical dropouts.
The QR isn't massively serrated, but it's not too bad(it was from a giant wheelset), the hub itself is relatively serrated.
I'm gonna test out a shimano ultegra QR and also thought of maybe putting some carbon paste on the dropouts, I'm also gonna tension the driveside spoke to max tension rating and the non drive to whatever keeps the wheel centered. What else would you guys suggest? Anyone else had problems with carbon dropouts?
I know I will most probably not get to use my max torque during racing as great power generated in a sprint doesn't require so much torque, but when accelerating it's definitely a problem, so I need a solution.
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Comments
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if it is this frame...
http://dengfubikes.com/uploadfile/produ ... 4117_3.jpg
...you can see that the qr clamps onto the mech hanger, take the hanger off and check there's nothing trapped between it and the dropout, also check that the mating surface is flat
otherwise suspect the qrmy bike - faster than god's and twice as shiny0
