[RD400 Problem]

I brought it and it had been rebuilt etc etc. So I'm not sure as to how well it's set up. Its got stock carbs, expansion chambers etc. The pistons are apparently a little oversize. I think the tank is venting okay, but I'll take the bike for a run tomorrow with the lid popped up to see if it is the problem. I'll check the airfilter too....

[RD400 Problem]

Hey guys, I have a 1976 RD400, and I have a problem.

I'll be gunning it along, and always, when I hit 7000, the bike seems to choke up and splutter., and refuse to rev more.

Is it retarded timing or is it needing a carb readjust?

Or is there anything else that you would suggest is wrong with it?

Advice/knowledge is kindly accepted, haha.

[SR250- SR250 bottom end SR400 top end?]

** and put the sr400 top end onto the sr250 bottom end?

[SR250- SR250 bottom end SR400 top end?]

I was wondering if it would be possible to use the bottom end of the standard sr250 engine, and take the top end, bore and piston from a sr400 engine?

Knowledge would be greatly appreciated!!!

Thanks!