Fitting new cranks.

Skinnaird

I may be a bit overly optimistic about my bike repair skills, but I'm presuming that I'll be able to fit a new pair of crank arms on to my Giant XTC SE without much trouble. Taking the old ones off should tell me all I need to know about putting the new ones on, right? Maybe? I've never fiddled around with this area of a bike before. I think my current ones are pretty standard, four bolts in an X, like this:

http://www.jandrhanson.com/Crankset.jpg

Can I just undo those bolts and put some new arms on? I need pedals too, but that's dead easy, I think. Just screw them on.

Any advice would be helpful.

supersonic

What crank do you currently have? What is wrong with them?

Skinnaird

Truvativ comp G. They look a lot like this

http://www.origoshop.cz/kliky%20s%20pre ... sefelt.gif

Couldn't find a picture of my cranks. Same sort of fitting, anyway. One of the pedals just fell out, on a flat section luckily. It felt loose, and then it went. It won't go back in again, the thread's stripped. I was told by someone who knows more than me that I'd need new pedals and cranks. Do I?

alfablue

depending on the type, you may need a crank extractor tool, though if it is a Hollowtech II you wont, but you will need the tool for the crank arm fixing bolt, TL-FC16 (alen keys for the clamp bolts). See the Shimano Service instructions.

Skinnaird

Well, it goes back in of course, but it doesn't screw in properly. It just falls straight out again.

Skinnaird

Righto. Thanks.

supersonic

You will need a crank arm and spider of the same dimesnions as the old one, best to take it into a shop. May be cheaper just to buy a whole new chainset! Swap the rings over, and then you have spares. Shouldnt need new pedals.

alfablue

Oh, ignore my last post, with that chainset you probably need a crank extractor like this for a square taper BB, or this for splined = I think the Truvativ Comp G is splined (ISIS).

Skinnaird

Ok. Sounding as if it might be for the shop. I sort of wanted new pedals anyway, as explained here:
http://www.bikeradar.com/forum/viewtopi ... 6#14562396

Thanks.

supersonic

Have a look at Wellgo V8 copies for about 15 quid.

Skinnaird

Great, just the pedals I was looking for. I'm undecided about the cranks. I suppose buying the tools and the stuff would still be cheaper than taking it onto a shop.

alfablue

I think a shop shouldn' charge much more than a tenner just to fit the cranks - a five minute job, so the costs would be similar, though it's nice to have ones own tools and learn how to do stuff. This Park Tools web page shows how it's done.

Skinnaird

Hmm. Pretty detailed instructions. I should probably try it, you have to learn these things one day... Cheers.