250 vs 400 pipes

[JNOYES]

Help!

I have a '77 MC5 400 and a '76 MC5 250.  Someone cut off the silencer/stinger from the 400 pipe before I got it and welded on a big spark arrestor.  I would like to weld a new stinger and silencer on the end to replace the spark arrestor. Today I pulled the 400 pipe off to clean it up and noticed how much it looked like the pipe on the 250.  I placed the pipes side-by-side and took some measurements and as far as I can tell the pipes are identical from manifold to stinger.  Is this true? Are the pipes the same, or do I have a 250 pipe on my 400?

Thanks

Jon Noyes

[tlanders]

I believe the 250 pipe should have a 7/8" diameter stinger and the 400 a 1 1/8" diameter stinger.

Teddy

[rob w]

Hi Jon,  
Yes, there is a clear difference between the two pipes. The head pipe on the 250 has one big sweeping bend up to, and making the first cone.
Where on the 400 pipe, the head pipe is made up of three 90 degree (apx) bends, 1st one right after the manifold turning to the left, the 2nd turning up vertical, and the last one sweeping back and forming the first cone.
I've been using a 250 pipe on my 400 since July when I crashed the original 400 pipe into a kinked-up mess. I don't know if I can even tell the difference between the two. Mostly because so much time had passed between rides. If anything, I think the 400 pipe will make better bottom-end, just abit sooner.

Bob

[Mike Lenz]

Bob, your correct for the frame breather. On the mc-5's the pipes are the same except for the diamiter of the stinger and the 400's was longer.

[rob w]

Hey Mike, Thanks, ya know I kinda thought that, because I've had a MC5 400. But to double check, I looked in the spare parts manual for 76+ MC5's and they show the 400 pipe to be like the 75's. Well anyway thanks.
Did you get that 79 rolling chassis from Bikerman on ebay?, I use to own that bike.
Seeya, Bob

[JNOYES]

Thanks for all your responses to my question.  So as I understand it, the pipes are the same except for the stinger.

[tlanders]

I think the header is supposed to be larger for the 400, 2 and 3/16 or 3/8 diameter instead of 2". I'm at work and don't have any info here.

Teddy

[Mike Lenz]

Teddy Teddy Teddy, Your confusing the issue! The frame breather header pipes are different. The 76-77 mc-5 pipes are the same except for the stinger. The 78 and on mc-5 and mc-80 snake pipes header pipes are different. Besides, Teddy, what are you doing on this site at work anyway?? Do your partners know about this??