PDA

View Full Version : Modifying 81-82 250r exhaust



morgan
03-11-2016, 07:16 AM
I've got a 82 250r that I would like a little more performance out of, I understand the stock exhaust are restrictive. Has anyone ever modified one? I'm a fairly capable welder, and wondering where the bottle neck is? Thanks

onformula1
03-12-2016, 12:30 AM
There is not a lot to play with there, find a Bassani and you will be very happy.

Just about any aftermarket silencer will work great with that pipe too.

morgan
03-12-2016, 05:02 PM
Any idea where to find one? Is there a classifieds section I'm missing, eBay hasn't been much help. Thanks for the advice, I'll know what to look for.

barnett468
03-12-2016, 05:45 PM
In addition to running a straight thru silencer, you can shorten the head pipe 10 mm if you want a little less bottom end power and more mid and top power with a few more rpm.

The compression is low on those so you will gain more power EVERYWHERE if you have the head machined which will cost around $125.00 . You will have to use premium gas and I would start with a 1 step colder spark plug like a B9ES.

If it has the stock carb, give it to someone you don't like . It is too small for that engine, especially if it has any mods . I would use a 30 or 32 mm . Mikuni makes one with a right side idle screw . Anyone that tells you to use a bigger one on a nearly stock engine is wrong . Bigger is NOT always better.
.

morgan
03-13-2016, 02:05 PM
In addition to running a straight thru silencer, you can shorten the head pipe 10 mm if you want a little less bottom end power and more mid and top power with a few more rpm.

The compression is low on those so you will gain more power EVERYWHERE if you have the head machined which will cost around $125.00 . You will have to use premium gas and I would start with a 1 step colder spark plug like a B9ES.

If it has the stock carb, give it to someone you don't like . It is too small for that engine, especially if it has any mods . I would use a 30 or 32 mm . Mikuni makes one with a right side idle screw . Anyone that tells you to use a bigger one on a nearly stock engine is wrong . Bigger is NOT always better.
.

Your referring to the aftermarket exhaust correct? And what compression and squish do you shoot for on these engines? I work at a machine shop so doing it myself wouldnt be a problem. Is there a application that used the 30-32mm carb so I can look for one?