Hi
My rear section of frame is out of line. That measurement of 4 inches and 3 13/32 just doesnt line up with the centre of the bike. I am about 8mm out. Now if you drop a plumb line down the centre from the front of the bike the 4 inches increases by about 8mm or so and encroaches into the 3 13/22.

has anyone dealt with this and what sort of approach should be taken? Should i rather try bend the two front sections of the rear section or try bend the back section to match the front? Will that 8mm have a massive effect on the bike?

Hi Brandon..It is not uncommon for the rear frame sections to be bent. This is the way I do them....
First, the position and alignment of the wheels is ultimately the only thing that matters.If the rim offset is correct and the rim is in correct alignment with the front frame then everything else will be correct. To this end fit (bolt up) the rear wheel into the frame and check the centreline of the rim against the centerline of the front frame..they should be in line with each other.
If the wheel is out, say 1/4" to the right when viewed from the rear, then remove the wheel and bend the left hand side of the frame that amount to the left. Refit the wheel to the frame, but don't tighten it up. You don't want the right hand side of the frame to have any 'influence' at this point. Pull it over to the left hand side and check that the two 'centerlines' are now in alignment. If they are remove the wheel again and bend the right hand side of the frame in to give the correct overall width as per the frame drawing..You will then have correct alignment and the right width at the wheel mounting points...Ian

email (option): ian@wright52.plus.com

Do you apply any heat on the frame when doing this Ian?

Hi Brandon..No, the rear frame is quite flexible without the rear wheel in place and will bend quite easily...(that is the problem!). Though they should be bolted to the front section to avoid bending the cross member under the saddle. Frame front sections do require heating being far more solid..Let us know how you get on...Ian

email (option): ian@wright52.plus.com

Thanks Ian. Will give it a go and report back in a few weeks.....still have to build up a rear hub assembly..

Thank you Ian! I'm at the same place as Brandon. We are both sharing notes on these rebuilds, and you have solved a problem for both of us.

email (option): britool51@hotmail.com

email (option): ahum@quicknet.nl

Also don't forget to check if the rear sprockets are in line. Before Henk's picture with dimensions I put in the gearbox first and line the gearboxsprocket with the rearchain wheel, then you know the hub is in the right position and you can spoke the rim into the centerline of the front frame.

And before fitting the tyres I put both wheels in line and two long straight bars vertically beside the rims and check if these are parallel so that both wheels are in the same plane, like the pictures below. Good luck, Michiel

Hi Michiel,

What are these pages from? Can I get you to scan them and email to me? I'll then share with Brandon.

If you can't scan them, would you tell me the name of the book?

Many thanks,

Robb

email (option): britool51@hotmail.com

Hi Robb,

It was a 2 page article in 'the classic motorcycle' from february 1991.

No working scanner so made pictures of the whole page. Regards, Michiel