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Discussion Starter · #1 ·
anyone have a guide
 

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'Supposed' to give you more power... Difficult to prove though...
 

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Yeah I've heard this also but how? How does it work? Benji
Quite simple actually...

All it does is bypass air from the air box directly in to the exhaust.
This allows COMPLETE combustion to take place in the exhaust, and therefore makes the emissions cleaner.

The theory is, that if you bung this thing up, then ALL the air has to go through the engine.
And more air to the engine = better.
I imagine this also does something to the backpressure...

Where I would question this, is that our engine doesn't adjust the fuel mixture on the fly as we do not have a lambda (oxygen) sensor in the exhaust so even if it gets more air to the engine, it wont get the extra fuel to the engine.

In an ideal world, it would work like this: More air, means more FUEL can also be added, therefore more bang. Same principle a turbo works on.
So that really just leaves the back pressure...
 

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Whilst it probably doesn't give any extra power, it COULD possibly make the engine a bit more responsive.
However, at a guess I would say the effects are more psychological.
 

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Arghh I get it!!! But yeahh I know that some exhausts don't have the whole to plug the pipe into so I guess covering hole will not ruin bike/engine?
 

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Arghh I get it!!! But yeahh I know that some exhausts don't have the whole to plug the pipe into so I guess covering hole will not ruin bike/engine?
No it wont damage the engine... Will just alter the fumes that come out the pipe :p
 

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Discussion Starter · #11 ·
Fisher said:
No it wont damage the engine... Will just alter the fumes that come out the pipe :p
Only thing that's bugs me about this why would you block off the one way value
Maybe we need to block off a different tube?

Sent from my iPhone using Forum Runner
 

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The best way to do it in my opinion, is to place a bung inside the tube, and then just reconnect it at either end.
That way it looks normal, and is easy enough to revert to normal.

Obviously if you are doing this mod because you HAVE to, then cut the pipe short, and bung it at the end.

I believe Benji (or someone else), removed the valve ALL together, and bunged it at the airbox, and therefore saved some very precious weight.
 
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Right, I remove the valve entirely, there is no need for an extra lump of weight sitting on one side of the engine also causing a dirt trap. Cut the pipe short to the airbox, then insert bung. Cut the pipe short to the exhaust and then insert bung. If I remember rightly the Leo Vince does not even have the facility to attach the air injection system. It is there to fool the emissions reading, there should be no combustion going on in the exhaust.

As for how it works, it works on reducing turbulence in the airbox, especially prone in on and off throttle positions, therefore promotes a more positive throttle response. We do a similar thing on an R6 race bike I have been involved with, and see approx 2 bhp extra mainly in the mid range. There is similar improvement on the Ninja's as well (have a set of ivans plates ready to bolt in).

Won't cause engine damage, ran them happily for over 10k mileage on my R125.
 

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Right, I remove the valve entirely, there is no need for an extra lump of weight sitting on one side of the engine also causing a dirt trap. Cut the pipe short to the airbox, then insert bung. Cut the pipe short to the exhaust and then insert bung. If I remember rightly the Leo Vince does not even have the facility to attach the air injection system. It is there to fool the emissions reading, there should be no combustion going on in the exhaust.

As for how it works, it works on reducing turbulence in the airbox, especially prone in on and off throttle positions, therefore promotes a more positive throttle response. We do a similar thing on an R6 race bike I have been involved with, and see approx 2 bhp extra mainly in the mid range. There is similar improvement on the Ninja's as well (have a set of ivans plates ready to bolt in).

Won't cause engine damage, ran them happily for over 10k mileage on my R125.
How much difference does it make to our little 125 engine... as 2bhp on an R6 would be a lot less different on little bike like ours. I am buying Leo Vince at some point so i guess i will have to bung it at some point anyway.
 

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The best way to do it in my opinion, is to place a bung inside the tube, and then just reconnect it at either end.
That way it looks normal, and is easy enough to revert to normal.

Obviously if you are doing this mod because you HAVE to, then cut the pipe short, and bung it at the end.

I believe Benji (or someone else), removed the valve ALL together, and bunged it at the airbox, and therefore saved some very precious weight.
ive done this aswell now, found some spare pipe and cut it down and blocked it off both ends, no one belives it makes a difference but most if not all the people whom have done the simple mod said they have noticed abit of a change but like you said it could be psychological :)
 

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How much difference does it make to our little 125 engine... as 2bhp on an R6 would be a lot less different on little bike like ours. I am buying Leo Vince at some point so i guess i will have to bung it at some point anyway.
Don't have a dyno plot for the R125, but it definitely felt better, did two timed back to back runs within a few minutes of each other with it on and with it off, and it was quicker with it off (i.e. bunged)
 

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Don't have a dyno plot for the R125, but it definitely felt better, did two timed back to back runs within a few minutes of each other with it on and with it off, and it was quicker with it off (i.e. bunged)
Maybe i do it in prep for my Leo Vince :D
 

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Right, I remove the valve entirely, there is no need for an extra lump of weight sitting on one side of the engine also causing a dirt trap. Cut the pipe short to the airbox, then insert bung. Cut the pipe short to the exhaust and then insert bung. If I remember rightly the Leo Vince does not even have the facility to attach the air injection system. It is there to fool the emissions reading, there should be no combustion going on in the exhaust.

As for how it works, it works on reducing turbulence in the airbox, especially prone in on and off throttle positions, therefore promotes a more positive throttle response. We do a similar thing on an R6 race bike I have been involved with, and see approx 2 bhp extra mainly in the mid range. There is similar improvement on the Ninja's as well (have a set of ivans plates ready to bolt in).

Won't cause engine damage, ran them happily for over 10k mileage on my R125.
When you say entire valve. Is it from the bit from engine near the start of exhaust and then to the exhaust????
 
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