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A new vibration

jagarra

Gerard
I had just finished the yearly ritual of flushing the brake system on my 11RS, among the other things I did was a canisterectomy and I changed the rear bit of the front fender to a longer style to keep debris off the motor front. Since my seat came back from Russell yesterday I figure today would be a good day for a ride. I was enjoying the new seat but also I could feel a vibration coming through the seat of my pants. First I thought it was the longer fender, but no, it was from the motor. I could feel it as I revved the motor, so I am trying to figure out what changed and if It was there all the time and I just didn't notice it before on the old seat. When i got back from my ride I put a sync gauge on the bike and they were balanced until I pushed it to the most sensitive scale, then off a little.

Before the Canisterectomy the throttle bodies were linked by a vacuum hose that was Teed to a vent from the tank. After that we just block the throttle bodies off individually so there is no longer shared vacuum. I mention this because when I had Kawasaki fours we always linked the carburetors vacuum ports as 1-4 and 2-3 with a hose, we felt it made the bike run smoother. So the question is has anyone noticed any changes after removing the canister.

I may link the ports again just to see if the vibration changes and satisfy my curiosity.
 
A new vibration UPDATE

Before I took my ride today I pulled the side panels off and ran the original hose with the T back to the throttle bodies, capped the T and I went for the ride. Bike was a bit cold blooded, but finally was working and idling good. I did notice less of the vibration or pulses that I was experiencing yesterday. Went on a spirited ride in the "cow counties" of Nevada, so few LEOS, speeds pushing ton or more . Mileage improved from yesterday (44.65 to 45.45) about .8 miles per gal.
 
To me that says you haven't been picky enough with the valve adjustments plus the throttle body balance.
 
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