Does anyone know about the intake manifold restrictors?
 

I have seen a website which says removing them in combo with "their package" of jetting filter and dyno time you get xyz increases.

Anybody played around?

Re: Does anyone know about the intake manifold restrictors?
 

When the VTR came out in 98 it had a tendency to die if you pulled the clutch and chopped the throttle, like when coming to a stop after a good run.
What happens is that the port velocity drops so much that it can no longer pull enough fuel from the carb to keep the engine running.
I used to be able to kill the 98 at will with the right combo of throttle/clutch.
In response Honda introduced the "restricted " manifolds that maintain port velocity and pretty much prevent the stalling.
I've ridden pre and after bikes and can't really tell a difference, other than that it no longer stalls.
Kai ju

What site is that?

http://www.dynobike.com/vtr1000_tips.htm

Is the only site I could find...and damn they got some high numbers for just jetting and filtering....on a stock exhaust...BS flag???

Aha! I was wondering if they were the source of this BS rumor. I believe what is pictured there (and I've seen that pic elsewhere) is the French model VTR that is horsepower limited. I've never seen that on a US spec bike.

However the place is in Australia, so I suppose they may have the horsepower restricted version too.

They are also wrong about the K&N Filter. On an unmodified VTR engine, you can expect to gain nothing or lose about a horsepower. It's also worth noting that they seem to give basically the same advice for every other bike.

So yes, I absolutely call BS. But I'm willing to give them some benefit of the doubt since they live upside down. :wink:

Re: Does anyone know about the intake manifold restrictors?
 

So a filter on a slip-on'd only motor is worthless?

Re: Does anyone know about the intake manifold restrictors?
 

Well, it'll be cleanable. But the stock filter flows more than adequately for the stock motor. A slip on really doesn't make any difference.

Years ago, a K&N was a must-have performance mod for most any bike. Not so much anymore.