Noobie question: Head tubes & Bottom brackets

[Jason B]

Forgive my lack of knowledge, I'm a noob.
I'm designing a scratch build, and I want to use a Schwinn springer fork. I cut these parts off a mountain bike I found at the dump. Am I good to go with this, or will I have compatibility issues?
It would be nice if I had a real Schwinn to compare to, but I don't.

 

[udallcustombikes]

If the donor bike had a three piece crank then you are stuck using a three piece. What is the length of the head tube?

 

[Jason B]

Head tube is 5 5/16" (five and five sixteenths)

 

[B607]

Postwar Schwinn head tube is 5 3/8". I just went and measured one. That's not counting the bearing cups...frame only. Since your lower cup (upper too?) is part of the tube, I'd say the Schwinn part will be too short for your frame. I suppose if you're clever enough you could grind off the cups. Gary

 

[Jason B]

So, with a proper piece of steel tube, I could use the bearing cups from virtually any scrap bike?

 

[OneHorsePower]

yes , any tube of the right diameter to fit the cups snug in it and the right thickness to be safe can do the job ,
after all that's what they started with to build the frame in the beginning :wink:
olny the threaded Botom bracket cant really be made by yourself ... but if you go with a one piece crank , you can find the right size tubing and just fit new bearing cups in there

 

[october]

Also,
If you we're to use a bottom bracket shell for a one piece crank,
You would have the option to run a one piece crank, or a three piece set up with one of the adapters...


Oct

 

[Jason B]

Thanks for all the help. 8^D

 

[Vintagebikelover24]

That head tub has a lot of room on the bottom. You could always take the cup out cut the tube down to fit a postwar Schwinn fork in there.

 

[Uncle Stretch]

These might help some. Just click the picture and the video will load.

 

[sensor]

2 things that no one mentioned thus far are the fact that if its a new bike that those are off of it will most likely be 1 1/8" headtube and the bottom bracket looks to be a Euro or maybe mid? Older Schwinns(aka made in U.S.A.) are going to be a 1" headtube and the older style B.B. (sorry I don't know the size but check Sheldon Browns site. it will have it.) will be bigger as well.
Hope that helps some.