Removing cranks without a crank puller?

I searched the forums but was unable to find anything…

I got my new cranks today and i would really like to put them on right now, but seeing as i don’t own a crank puller and the bike shop is closed by now. What exactly can i do to get the old cranks off?

Thanks.

well do as i do, gently beat it with a hammer…

Chase

how can i get to the crank with a hammer? do you do it through the spokes somehow?
i would have experimented with it, but i dont want to mess anything up.

well i just gently tap the sides of the crank and that will loosen them up a little, and if that doesnt work, i just pull and yank and twist till im really frustrated and they eventually come off… so yeah its not a very good system, i recomend buying a crank puller…

Chase

… good luck hitting the crank w/ only a hammer… you need some kind of punch to go through the spokes and if you don’t want to scratch the cranks put a small board between the “punch” and the crank … and hit as close as you can to where the crank meets the axle … i have posted about this before… and it may help to hold the crank/pedal off the ground by putting the wheel on your legs

a big bolt usually works as a “punch”

The safest way to do it is: DONT do it! no matter how bad you want the new cranks on , are you willing to risk damaging your uni and still not getting the cranks off and still have to go to the local bike shop…

haha…man this is a tough choice.
i will go take a look at it. see if i think i can do it. if not…then the guys at the shop will be seeing me bright and early tomorrow.

I have never had a problem w/ the way i do it

Use a crank puller. The less extra impact and wear you put on your hub, the better. Plus it’s so much easier. Be patient, wait till your shop opens, then go buy a puller, and you never have to wait again.

I’m going to echo what madmatt said. You might not have a problem the first time you use a hammer, or the 2nd, but the process of using a hammer applies forces to the hub and cranks at angles that could cause the metal to deform, weaken, or even crack (microscopically).

Generally the hub is made of a metal that is harder than the cranks, and the cranks are the first to deform… so you probably won’t be able to get a good fit from hammer-removed cranks after the first or 2nd removal. Weakening your hub is never a good thing… especially a square-taper hub. It’s like playing russian roulette… you’ll never know which big drop will lead to a disasterous hub failure. Do you really want to risk a bruised pair of 'nads?