Singlespeed & Fixed Gear - question on bottom bracket

i recently bought a '76 Raleigh Grand Prix. I the bottom bracket was completely ruined. i need to get a new one. I have a bunch of mountain bikes that are being put to use and i was wondering if i could use the bottom bracket off one of those. Would it fit or is there a special road type?

It might work depending on the spindle length and some mtb are 68 shell and some are 73 so that part may be too wide.

Quickest way to solve this problem is to take it to your lbs and have them install a new one. It shouldnt cost you more than $30 incl labour and possibly as low as $15. The slower way is to figure out whether your raleigh and mtb bb's match across three parameters:

1. bb shell width
2. bb spindle length
3. bb threading type.

You can get info about all this stuff at http://sheldonbrown.com/gloss_bo-z.html#bottom . I would classify this project as "hard for a newb" so unless you enjoy this type of thing you might want to lbs it.

Edit: A "hybrid" approach would be to go to your lbs and have them figure out what kind of bb you need, then buy that bb along with a bb tool & crank puller from them and do the rest yourself. Thats how I did my first bb replacement. With the tols it may well cost you more than a straight up bb replacement but you will have profited by gaining some knowhow.

Double edit: If youre planning to convert this raleigh to fixed/ss that opens up a whole nother can o worms with chainline.

The 76 Grand Prix uses the old Raleigh style threading, so you're not going to be able to easily switch anything out. Your LBS should be able to put in a new one for you though. I rebuilt a 76 last summer, cottered cranks and all, but couldn't find a replacement spindle because it wasn't even the standard spindle width so you can't just switch the spindle out either. Just LBS it.

The 76 Grand Prix uses the old Raleigh style threading, so you're not going to be able to easily switch anything out. Your LBS should be able to put in a new one for you though. I rebuilt a 76 last summer, cottered cranks and all, but couldn't find a replacement spindle because it wasn't even the standard spindle width so you can't just switch the spindle out either. Just LBS it.
First person in this thread who knows what they are talking about!

Read this about Raleighs to understand why you will have trouble: http://sheldonbrown.com/raleigh26.html

The 76 Grand Prix uses the old Raleigh style threading.

Huh, really? I guess I've never done a Raleigh that old. What's different about the threading? Is the thread pitch different?

The tpi is different, as well as the diameter of the spindle hole.