Vintage Dirt Bike Q & A

I have seen a few bikes at the races that use 450 or 480 swingarms to replace the steel original unit in their 78-80 cr250. One thing i am unsure of though is then you weld the tabs on the swingarm for the dual shocks, do most re-heat treat the swingarm or is this not an issue? Thanks for any advice on this.

It's not an issue.

Those swingarms were cold worked and tempered by artificial aging.
The heat from TIG welding shock brackets won't affect their strength.

I TIG weld skid plate and case guard mounts as well as finish the
factory beads on my aluminum framed CRs without any problems.
The new frames use the same type of aluminum and manufacturing
process as the old swingarms.

dogger

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1973 CR250M
1979 CR250R
1993 CR250R
2008 CR500R
2009 CR250R

Will the swingarm bolt up to a 79 CR250 without modifying?

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Terry Moody #48f
3x 74 Honda CR250M Elsinore
74 Honda XR75
73 Honda QA50
78 Yamaha YZ125E
78 Yamaha YZ250E
78 Yamaha YZ400E
79 Kawasaki KX250
79 Honda CR250R
79 Suzuki RM400
80 Honda CR125
2x 83 Honda CR480R
98 Kawasaki KX250