Compact crank issue



Scary ride today in a way. DOing Seated stomps really hard from low speed and big gear (50/14) and chain was now popping off the big ring to the outside!!


I called my LBS as soon as I got home and he called SRAM and I should have new chainrings by Friday. Thanks LBS and SRAM, but glad it didnt come off in a big gear out of the saddle sprint-ouch my family jewels!!!
 
rayhuang said:
Scary ride today in a way. DOing Seated stomps really hard from low speed and big gear (50/14) and chain was now popping off the big ring to the outside!!


I called my LBS as soon as I got home and he called SRAM and I should have new chainrings by Friday. Thanks LBS and SRAM, but glad it didnt come off in a big gear out of the saddle sprint-ouch my family jewels!!!
My FSA compact has always worked fine. I think the manufacturers are still working out the bugs on the compatibility issues. Shimano apparently has their compact dialed in with their own chainrings, chain, and deraileurs. But I think the rest are still tweaking and have to make it compatible with Shimano or SRAM chains. I always usd the lemon law principle, give a LBS two shots to fix a problem, then you might want to have them switch to Shimano and give you a credit for the stuff that doesn't work right. The tolerances are very tough for this type of drivetrain and you need a good LBS and products past the tweaking stage for everything to work well. Once it is dialed in, you will never look back
 
kopride said:
My FSA compact has always worked fine. I think the manufacturers are still working out the bugs on the compatibility issues. Shimano apparently has their compact dialed in with their own chainrings, chain, and deraileurs. But I think the rest are still tweaking and have to make it compatible with Shimano or SRAM chains. I always usd the lemon law principle, give a LBS two shots to fix a problem, then you might want to have them switch to Shimano and give you a credit for the stuff that doesn't work right. The tolerances are very tough for this type of drivetrain and you need a good LBS and products past the tweaking stage for everything to work well. Once it is dialed in, you will never look back
I agree theres not a lot of room for error in these Shimano 10 speed drivetrains. I dont think this little LBS has the experience in these 10 speed drivetrains to be of much help. Sadly to do it right-there are some very proffesional mechanics in town and I'd have to pay $120 or more for a tune-up. I am not cheap-I just dont like paying for things while they are "under Warranty" or new and not working.
 
SRAM sent express mail to the LBS a set of new chanrings. Now of a significantly different loking tooth design, ramps, etc. Also now made from anodized or hardcoated aluminum.

Shifting is smoother in all respects (up and down) and I had to readjust my front derailleur as it needs less throw to shift and it doesnt require as much fine adjustment to not rub in the extreme gear choices 36/12 and 50/21 (11-23 cassette).

But, sadly it still comes off the chainrings in the 50/11 peddling backwards, but only the 50/11, not the 11,12,13 like before. I also did some serious stomps in the 50/13,12,11 and it did not come off the chainring.

This was all on a windtrainer. Tomorrow's the acid test when i ride outdoors and find some good rollers and climbs.

Thanks for everyones help,
Ray
 
rayhuang said:
hey guys,

Very frustrating on a new $2200 bike. Worse I think my LBS owner is just swamped, understaffed in his little bike shop so its hard for him to be very active on this matter.
Take the bike back - leave it there - get a refund - and take your business somewhere else.
 
John Rupp said:
Take the bike back - leave it there - get a refund - and take your business somewhere else.


I have thought of that as a last resort, but I am not that type of person.

Heres a wonderful gesture on the part of th LBS. I got this via e-mail today.

Ray, I am ordering a ultegra level crankset for you, I can't remember
if they make an ultegra, maybe it's called r700, (between Ult and D/A)
whatever, I don't have time to look now but I just had to respond to you
right away.

I've had hints that truvativ is not as good as shimano but this is the
worst. I even checked your frame alignment and it is fine.

The first hint that a part might not be as good for a bike is when it
is not a shimano part. Starting about five yers ago we went into
another cycle of going to non shimano cranks and brakes. Shimano is dropping
it prices to oem now so we may start seeing shimano crank equiped bikes
being sold more againg.

Personally I am not a fan of shimano or loyal to them, it is just that
it works so well, that shimano is the way to go. From a marketing
standpoint and from a cool factor standpoint Shimano may not have that zing
bling thing, but they design all their stuff to co-ordinate together
and it works best together.

Everybody else is trying to get their market share but Shimano holds
back crucial engineering information from the other manufactures.
Shimano tells them just enough to get on the road. The other manufactures
know the next generation is coming but can't wait for the actual
production pieces to engineer from be cause that would put them a year behind.
And they can't retool next year unless its a total disaster because
that'll drive the cost up. So on and so on. A blend of my opinion and
opinions and facts I've picked up talking to those in the industry.

I am putting in the order tomorrow or tuesday.
Sorry we have to deal with this but we will deal with this.
 
To have closure-a Shimano Ultegra Crankset (53/39) has solved every problem and the drivetrain is now smooth, fast shifing, quiet and no stupid issues like chain falling off anymore.