I have a 2007 Fuji road bike. I would like to change the cranks. I removed the hex bolts, thinking the cranks would then come right off. They're not. Do I need some sort of tool for this?

The bottom bracket has square spindles. My new crank accepts square spindles. I'm hoping this is a simple swap job?

I probably should have asked these questions before, but this all seemed pretty straightforward. Guess not!

Thanks!

You need a crank puller.

Awesome.

I assume the correct use of this tool should be pretty self-evident once it's in my hands?

Are there any other surprises I may be in store for? Just trying to avoid multiple trips to the LBS.



Thanks for the quick reply!

Well, you will probably need a matching bottom bracket for your new crank (unless it uses an identical one to what you have now). If so you will need the appropriate tool to take out the old one and install the new one.

Crank pullers are pretty simple. Just make sure that you thread it into the crank all of the way. If you don't you risk ruining the threads of the crank. When you install the new one, torque the crank bolts down very tight.

Watch the threading of the part that goes into the crank arm. The threads are very fine and it's super easy to cross thread them. Be gentle and if it doesn't seem right ease it out and try again. Some cranks with sloping shapes in that area have partial threads on the "deeper" side that can fool you and make it hard to catch the thread correctly. The big deal here is use only two fingers and if you can't turn it with those then back it out and try again. Force will kill you in this issue. Use all your skills as a master criminal safe cracker to get it right...

Oh, and your new crank puller will thank you if you grease the threads on the inner pusher pin threads. But I'd leave the outer crank engagement threads dry or just use a very light oil on them.

If the threads in the crank are super muddy or otherwise gummed up you really should clean them out first. The mud or grime will make it harder to feel the threads on the puller going in right.

Thanks for all the help. I got the right tool for the job, and it was indeed pretty obvious how to finish the job. It took a surprising amount of elbow grease, but I guess it's a relief to know that I was riding cranks that were very securely fastened!

I'm convinced that my new cranks aren't squeezed in as tightly as the old ones. Although I tightened the hell out of them, they just seem to project laterally a bit more than I remember the old ones doing. This is evidenced by the fact that the FD shifts fine between the smallest & middle chainrings but can't seem to engage into the largest. (This is a triple crank, in case I didn't mention).

Should I somehow try & force the cranks further in? Or am I simply better off loosening the H screw on my derailleur?

If the crank bolts are tight, and you are close enough then go ahead and adjust the derailleur.

The worst case situation here is that the new crankset was designed for a different axle length in the bottom bracket. If the derailleur cannot be adjusted, or if the chainline is obviously wrong then you will have to replace the bottom bracket with the proper length.

For a quick crash corse in this, read the sections in the Sheldon Brown articles about chainline, cranks and bottom brackets.

There's bound to be minor variations in the taper. Also each time the cranks are mounted they'll pull on just a hair farther because of the stretching and wear on the inside of the taper. Just re-adjust the derailleur screws.

Also I know it seems odd but the tapers actually tighten themselves as you ride the bike. I tighten the snot out of my bolts as well but every time I've taken them off the screws area darn near loose and the crank takes a lot to remove.

Just for a lark try removing them now. You'll likely find that even with all your sweating to mount them that the puller will have little trouble popping them off. Remount as before and go ride for a year or so and then try to remove them. The bolts will be only a fraction as tight as you left them and the cranks will be hard to remove. It's as sure as death and taxes...

grease all metal to metal contacts. square tapers and hex bolt threads. that is all.

Make sure.. when you pull the crank .. you tighten the crank puller bolt all the way down into the crank with a wrench. Most of the time finger tightening can leave you with a stripped crank.

Got my FD adjusted and I'm good to go. Had to back the H limiter screw way out, but it's shifting pretty smoothly so I think I'm in business.

Thanks for all the help!