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Vacume Problem

N

nsmisner

Tricycle
My bike has been hesitating from 4k - 5k while accelerating. I messed with the vacume hoses and fixed it by taking the Air Switch Valve out of the circuit. What problems will I cause if I just cap the vac tube on the switch valve?
 
This is something I know very little about. Are you talking about the vacuum switch that is above the valve cover that operates the reed valves? If so I think that entire system can be bypassed and the reed valves removed but I don't have more info then that. ---------------------------------- I will answer any question. It is up to you to figure out if I should have.
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<p align="left"><a href="http://www.flickr.com/photos/20211686@N05/">My Photos<br
 
If you want I can try and track down the info to remove the system. The other option is buy a new vacu switch and fix it back like it was. All the system does is help add O2 to unburnt fuel after it leaves the chamber so it will burn off the rest of the way. Good for the environment I guess. ---------------------------------- I will answer any question. It is up to you to figure out if I should have.
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<p align="left"><a href="http://www.flickr.com/photos/20211686@N05/">My Photos<br
 
As long as you have the vacuum attached to the petcock and plug the aire box openning you'll be fine. Several members have done away with the reed valves entirely with not ill effect. Yes the system is designed to re-burn un-burned exhaust gases that might leak up into the upper part of the engine, but in reality its effectiveness is marginal and has no real beraring on the operation of the machine. AKA "2linby" That's 2-lin-by folks! Northwest Area Director COG #5539 AMA #927779 IBA #15034 Team Oregon MC Instructor
 
You Cannot do away with the reed valves entirely unless you tap the ports in the actual valve cover and thread in some set screws. Th easier way here is to leave the reed valves and metal covers on the valve cover, and remove all the vacuum hosing associated with the pair valve. Go to your local auto parts store, and pick up three 5/8" "heater core block off caps". They look like big vacuum caps, and also some 3/16" regular vacuum caps. Using the 5/8" Cap off the 2 ports left on the valve cover, and insert one backwards into the airbox hole. Use the 3/16" to block the intake ports. You're done! steve
 
Bob is correct. It is a good, simple system that allows the exhaust system to pull fresh air into the header tubes between exhaust pulses (low pressure periods). That burns up unburned fuel. I am the furthest man from a tree-hugger you're likely find, but it IS good for the air we breathe. It uses no power, no fuel and it's only downside is some exhaust popping on overrun. It might also screw up mixture readings on a dynomometer. I say fix it as soon as practical. Run as is 'til then.
 
What Steve said.... I have done this on 3 Kawasaki four-cylinder bikes including the Concours and it works great.
 
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