2 into 1 gremlins

[Jonesey]

Hi all, I've recently fitted a 2 into 1 system to my vtr, with a full length race can with no problems, no rejetting etc.
Today i replaced the full size can with a much shorter carbon can, and there is a flat spot at 6-6500rpm??
What gives??
What I want to know is, is it now too rich or too lean at this point?
Or is it some other issue?
I have since swapped the cans again and bike is back to normal- what caused it, and will tweaking it leaner/richer solve the problem? Or is it £dyno£ tiime?
Your thoughts??? more the merrier!!!
Thanks, Chris.

[donk]

Its loud aint it matie!!!!! The old bill are going to love you, infact so are your neighbours!!!

[coledog]

if you have a decent 2into2 leave alone looks better imo, and prob. runs better

[Phil-VTwin]

The shorter can probably mucks up the scavenging pulses in the pipes, exhaust tuning is just as important as intake or engine tuning regarding pipe diameters and lengths.

[Phil-VTwin]

Here is an article that explains it very well, much easier than i was taught!!

http://hemrickperformance.com/aboutus.aspx

[sirch345]

The shorter can probably mucks up the scavenging pulses in the pipes, exhaust tuning is just as important as intake or engine tuning regarding pipe diameters and lengths.

That would be my 2p worth as well

Chris.