I want to start my build and have decided taking the stretch way.
Pushing the aluminum cold makes me think it would crack faster. Do you guys heat the frame and how much? Have anybody welded their front mountings with a mig or should I stick with a tig job only?
Stretching the frame
This method has been done a few times...
PRO's:
Easy
Cheap
Works
Con's
You gain mount and waterpump clearence, but still have to dick around with pipe clearence
Some frames need more pushing that others
Some frames push easier than others, like their softer
You should mock it up, and see what your up against. If it only needs a slight push, consider it. It it needs 3/4".... pass.
Heat the frame up first, the whole frame, not just the cradle.
Personally,I would replace the "Y" with a Gen4 cast one, and have new rails bent for the cradle. Remove the old one at the foot pegs.
Tig.... Always.
PRO's:
Easy
Cheap
Works
Con's
You gain mount and waterpump clearence, but still have to dick around with pipe clearence
Some frames need more pushing that others
Some frames push easier than others, like their softer
You should mock it up, and see what your up against. If it only needs a slight push, consider it. It it needs 3/4".... pass.
Heat the frame up first, the whole frame, not just the cradle.
Personally,I would replace the "Y" with a Gen4 cast one, and have new rails bent for the cradle. Remove the old one at the foot pegs.
Tig.... Always.
-
asteroid500
- Posts: 1047
- Joined: January 5th, 2009, 1:29 am
- Location: Australia Melbourne
[quote=Not a ton of movement needed[/quote]
WTF ... i dont meen to burst your bubble, but thats alittle more then a push away ... having said that, i've never done a G3-4
Take the advice so freely give mate ..... i'd cut & tig if it were me.
just my 10 cents worth.
WTF ... i dont meen to burst your bubble, but thats alittle more then a push away ... having said that, i've never done a G3-4
Take the advice so freely give mate ..... i'd cut & tig if it were me.
just my 10 cents worth.
"not speeding officer".....qualifying
CR250 97
CR500 AF 99 (in progress)
CR500 AF CR G-4
CR500 1985 true legend
RGV250 96 X2
GSXR600 07 TRACK BIKE
VH Commadore cup car (race)
CR250 97
CR500 AF 99 (in progress)
CR500 AF CR G-4
CR500 1985 true legend
RGV250 96 X2
GSXR600 07 TRACK BIKE
VH Commadore cup car (race)
Mine went about 6mm in the center over 55-65mm length. So the taper is ever so slight and barely noticeable unless your looking for it.
But as Bob says, you can redo the cradel. So if you salavage the mounts wheres the harm in trying. If it dont work out do it another way with very little financial outlay.
I reckon the hot tip is if someone can make an adjustable jig, attach the front mounts to the jig, push it to desired position and weld it in one application. Let the heat settle with your rails in the new position.
The thing is the frames bend easy, the part that is NOT easy is the spring back. For example you may push it 15mm with next to no force, when you release it will spring back to pretty much where you started from. This is the tricky part because you have to gradually go past that point so the spring back is less each time. If you get impatient and try do it in one go you would require more intial force than what it will happily bend at and risk breaking it.
But as Bob says, you can redo the cradel. So if you salavage the mounts wheres the harm in trying. If it dont work out do it another way with very little financial outlay.
I reckon the hot tip is if someone can make an adjustable jig, attach the front mounts to the jig, push it to desired position and weld it in one application. Let the heat settle with your rails in the new position.
The thing is the frames bend easy, the part that is NOT easy is the spring back. For example you may push it 15mm with next to no force, when you release it will spring back to pretty much where you started from. This is the tricky part because you have to gradually go past that point so the spring back is less each time. If you get impatient and try do it in one go you would require more intial force than what it will happily bend at and risk breaking it.
13 isnt unlucky i just keep falling off
I was giving it some thought about a new cradle, but decided that it was too extreme for my first build and then I stretched her. I pushed the rails out but they just kept coming back, moved the jack around on the cradle and it started stretching. My frame rails had to move about the same distance as the one in the pic of gmbond , its crazy how far you can push these rails without cracking. When cutting the front mounts of I only removed the flat pieces that touched the motor and not the L section of the mount welded to the frame. Cutting so close to the frame makes me nervous and I thought of leaving it and only welding the old flat pieces back to it. Would that way be okay or will I be nigivering it?