Compatibility of early RM and PE expansion chambers - 250cc models

[James P]

Can anyone advise whether an RM250A, B and/or C model expansion chamber can be fitted to a PE250B, C or N model without modification to mounting points?

I am fairly certain that silencer mounting points are different, but always thought that the three mounting points for the main chamber portion (i.e. cylinder stub manifold, right-hand front frame lug and left-hand rear frame lug) were in the same relative positions for all these early RM and PE models.

Since I lack enough parts to try out the theory for myself, I am hoping someone has already investigated and can advise accordingly .

Thanks & regards,
James

[suzuki27]

Some are same figment. I have an nos PE250C pipe which I fitted to my RM250B. The mounting points are the same. I sold the RM but still have the PE pipe

[brent j]

Some are same figment. I have an nos PE250C pipe which I fitted to my RM250B. The mounting points are the same. I sold the RM but still have the PE pipe

Out of interest, how much do you want for the PE pipe?

Thanks

Brent

[James P]

Out of interest, how much do you want for the PE pipe?

Thanks

Brent

Doh! I was going to ask that - you beat me to it Brent!

S27 - Thanks very much for the info...and can I please have second dibs on your now-almost-NOS PE250C pipe??

Regards,
James

[suzuki27]

PM sent guys

[shelpi]

yes they fit I have A RM250B and a PE250B,C the only difference is the baffle in the chamber of the PE and spring location for the muffler

[James P]

PM sent guys

Thanks - replied.

yes they fit I have A RM250B and a PE250B,C the only difference is the baffle in the chamber of the PE and spring location for the muffler

Excellent - thanks for confirming what I thought I knew . Should it follow that pipes for all 77-79 PE250, 76-78.5 RM250 and 76-78 RM370/400 are physically interchangeable...?
If they fit, I'd be interested to hear from anyone who has tried an RM370 or 400 pipe on a PE250 (or even vice-versa for interest) - is there much/any obvious difference in the shape, length or volume (internal space, not loudness )? Any observations on performance?


Thanks & regards,
James

[suzuki27]

I think the header diameter on the 370/400 will be too large to fit the 250 manifold.
I did try a PE250T chamber on my RM250T and it made it a little slower but seemed to give it more torque - better for mx on a rough track I thought. It is to do with the baffling and mellows the delivery

[James P]

I think the header diameter on the 370/400 will be too large to fit the 250 manifold.

Yes, you're right of course. I'd forgotten that the RM370 used a different exhaust stub manifold on the cylinder.

Regards,
James