sprocket repair

Question
I have a Mongoose Scorch mountain bike and I bent the sprocket.  I don't think the crank is bent and I was wandering if it is something that I may be able to fix and repair myself. Thanks

Answer
Rob,

Whether you can repair it yourself depends on how badly bent it is.  Oh, and by "sprocket" I assume you mean the front chainring. (since you mentioned the crank, I figure you are talking about the front).  Technically, the "sprockets" (gears) are in the back and the "chainrings" are in the front.

If the chainring isn't bent badly, you can try to fix it yourself.  Find the biggest Crescent wrench (adjustable wrench) you can.  The Crescent wrench should have flat blades and no gripper teeth.  Narrow the opening as much as you can and slide it onto the chainring.  Move it over the bend and slowly and carefully twist the bent section back into place.  Two things to think about:

1.  Bend back using a lot of small twists instead of just big one.  You will run less of a risk of breaking it.
2.  If the chainring is aluminum, it may break in bending it back at all (aluminum has no fatigue strength, so it can be bent once and then if bent back it sometimes breaks).

If the chainring breaks, don't worry too much.  Replacements are rarely more than $25 if you shop around.  Installing a new chainring is pretty simple, requiring only an Allen (hex) wrench.  

Let me know if there is more I can clarify for you,

Graeme