In my tests/adjustments on an old 2V K100rs, I found that I could balance cylenders 1,2 & 3 at approx 10" Hg.
#4 however seems to be consitantly low reading only about 1/2 the others and the bypass air adjusting screw seems to have little or no effect in the readings. It does not appear that anyone has tried to make any adjustments on the linkage screws.
I did try moving the linkage screw in & out on number 4 only, paying close attention to getting it reset back to it's original position. No amount of fiddling in either direction improved the reading at the gauge port, (I have checked & rechecked the valve clearances and have all new rubber boots & manifolds, including a new breather hose. The system has been checked & rechecked for air leaks, none found.
I find it curious that #4 is low even with the air bleed screw seated fully closed. On all the others, closing the screw raises the vacuum reading, opening the screw lowers it.
My question is: With #4 being consstantly lower than normal, would that cause the FPR to create more pressure at idle than would normally called for? What do you think about moving the FPR vacuum line to #3 since the vacuum there seems to me more "in spec"?
Can I assume that because #4 is low and unresposive to adjustments.... that I probably have a defective intake valve on that hole?
I have yet to get a 12mm adaptor for my compression gauge so I can not test compression at this time.
Inge K. wrote: Agerbundsen wrote:So what vacuum level should one expect at the throttle bypass?
It isn`t any specific value for this, since it`s much different things that affect this value.
And it can vary on the same bike over time as this and that are worn, and different maintenance
tasks is done, what is important is that all four cylinders is adjusted to the equal value.
But by memory I usually end up somewhere around -0,4 bar at idle, others in here might have
other experience about this.
Inge K.