: Bicycle gear slip repair.


ertman
May 25th, 2010, 02:15 PM
I am not that bicycle-mechanically inclined, and have recently ran into a problem.

When pushing the pedal with some force the front gear will slip and while the pedal will move, the gears and chain don't. It is an inexpensive CCM bike, but I was wondering if anyone know what the problem is and whether I can do anything about, or should I just take it to a repair place.

MLeh
May 25th, 2010, 02:43 PM
Is it a multiple gear bike? Could be that your cables have stretched and derailer (derailleur for purists) isn't aligned properly.

Probably you should just take it to a shop.

l84toff
May 26th, 2010, 12:49 AM
I had the same thing happen on a cheaper bike that I had quite a few years ago. I took it into a shop and it helped. But the problem came back. I blamed it on cheaper parts. Now I ride a Kona Cinder Cone and love every bit of it. Incidentally I no longer experience that problem, even 6 years later on the same bike with little more than an annual tune up. And I usually put over 1k on the bike a season. Used to do a lot more when I was single and had lots of time.

This is seriously a good reason to spend the money on a better bike. It may seem like a lot of money to spend $600-$1000 on a bicycle but after 10 years or more of nothing but enjoyment, you'll think it's worth every penny. You're actually paying for higher quality components.

Of course if you only put 100km a season, that's probably a waste of money.

ertman
May 26th, 2010, 08:00 AM
Thanks to all so far.



While this CCM bike has served me well over many years. because of the age of the bike and its current condition, I was planning on buying another bike in the next year or so. I was also planning on buying a more expensive one to get a little better quality out of it. I'll look into the shops to see if they have anything else to add.

Is it a multiple gear bike? Could be that your cables have stretched and derailer (derailleur for purists) isn't aligned properly.

Probably you should just take it to a shop.


It is a 21 speed. I do not see a failure in the derailleur, and I can replicate the failure by putting weight on the bike and pushing with my arm to see what is going on. It would appear (don't know if this is the case) that the front gear set is possibly press-fitted to the crank and with enough force it can be rotated independently, creating a slip.

Because of this problem, I think that this would have to be replaced, and as the bike is old, I would rather not get too much into repairing it.

chimo
May 26th, 2010, 09:24 AM
If the front chain ring is not turning it could be your crank arm. If you have a style that takes cotter-pins, they tend to deform and cause this type of problem.

+1 on the comment of $600-1000 for a bike. This seems to be the "knee of the curve" for value for money.

Check out the link "Cottered Cranks" on the page below.
Harris Cyclery articles About Bicycle Repair (http://sheldonbrown.com/repair/index.html)