OK you choppin fools, how about a little help here...some photos...

I'm trying to fit a 'J' motor into a
GPx frame. I will have to cut the down
tubes just above where they bend from
an inverted 'V' to parallel. I will also
have to cut the bottom tubes where they
are parallel to the ground, just before
they bend up. In place of the cut out
section I'll need tubes that are 15"
apart instead of 12" (on the inside)
in order to clear the pipes. These tubes
also need to be a bit more vertical than
they are now. Closer to the same angle as
the police frames.


My question is, how do I keep everything
lined up while I cut and weld. Will the
top tubes keep things straight enough (how straight is
straight enough?) or do I need to build an jig?

Aside from the downtubes interferring with
the 1-4 head pipes, the 'J' motor is about half
an inch too long to cram in the frame as it sits.
Picked it up and tried to wiggle it in there
and it just didn't want to go

Thanks,

-Duck

Post edited by: Duck, at: 2006/01/25 18:05

Post edited by: Duck, at: 2006/01/25 18:07

Jig it. You'll thank yourself later. It needs to be straight,real straight

Thanks. Would rather get it right the
first time.

Need a few nitpicky pieces just to get
her running. Two cam cap hollow guide
pins, and one shim bucket. Blower work
comes after getting the ride right.

I'll try to get it jigged on Friday.
Do you think front to back cross brace
welded just beyond the section I'm
cutting out will do the trick?
Don't know wall thickness so need to
get the section out to order some material.

Have changed mind and will weld up a rigid jig
with tight tube through swing arm pivot and another
through the neck. This way I can make sure I'm straight
no matter how much I cut out and replace...


-Duck

Post edited by: Duck, at: 2006/01/26 08:12

This is where I am now with my 1977 KZ 1000 A1 frame, Using a simple jig, NEW DOM Tubing and a lot of checking and re-checking all is well. I hope you have fun with your Chopper Build. Cheers Dan.


My PIC is to large to put in this form.

Post edited by: dog pound, at: 2006/01/27 13:47

Post edited by: dog pound, at: 2006/01/27 13:48

Sent you email so you'll have mine.
I just put a note on buddy's desk to order a stick
of 1 1/4 0.095 tubing for me when he puts in his next
order with JM Tull.

I spent some time measuring today and it looks like I'll
be able to bend the new down tubes, weld then to the old
tubes, and then cut out the old tubes. The bottom tubes
are a half inch closer together than the bottom tubes on
the police bike but there is 1/2 clearance on either
side of the engine case in the police bike frame.
I think 1/4 inch will be enough so I'm leaving the
bottom tubes.

-Duck

Hay duck I hope the pic's help. when joining / welding the to tobes together you will see you that the inside dia of your current frame is larger than new DOM tubing. I, would get some solid stock steel and make slugs, usually twce as long as your dia in lenght. 3" inserted inside each end.It will help reinforce and give you more to weld to.

Post edited by: dog pound, at: 2006/01/27 15:23