Engine Power not good

OK guys I posted once about this problem and have got some things done since the first post. Here is the original problem. The bike (KZ750-M1 CSR Twin) will not go over 55 MPH on the highway. Here is what I have done so far Checked compression and get 120 on the compression according to my manual anything above 114 is serviceable. took the coil and igniter to Kawasaki shop and had them tested no problem with them. Finally got a new Valve cover gasket for it so got the valve cover off and checked valve clearance here is my question the manual says valve clearance should be between .05MM to .10MM the 2 valves on the right side sitting on the bike are at .102MM will .002MM make a difference I know on a car I would not worry but I know a bike is different will it run correctly with that amount off on clearance. I wanted to ask before I put it back together. I also had a broken throttle cable it was snapped at the handle and didnt know it. Also when I took the coil to Kawasaki I found out that the coil had the wrong type plug wires on it. I was told that the wires on it were suppression core and I should have copper core with resister ends so I ordered wire and ends from Z1 (my coil wires can be removed and changed). thanks for any help you have all been great help to me so far. I know a lot about cars about anything you want to know but a bike has been a different beast all together but I am learning.

First off, I'd like to know what you are using to measure valve clearance to .0001" (.002mm)? That's an awful precise measurement, and at that level, whatever you are using to measure with better be certified by NIST (if you are in the US anyway).

Assuming that is an accurate number, it's irrelevant anyway, simply call it .10mm and let it go. The only thing I have that is capable of reading to .0001 inches is a dial test indicator, and I wouldn't even put much faith in that, since it's at it's limit at that point.

steell wrote:

First off, I'd like to know what you are using to measure valve clearance to .0001" (.002mm)? That's an awful precise measurement, and at that level, whatever you are using to measure with better be certified by NIST (if you are in the US anyway).

Assuming that is an accurate number, it's irrelevant anyway, simply call it .10mm and let it go. The only thing I have that is capable of reading to .0001 inches is a dial test indicator, and I wouldn't even put much faith in that, since it's at it's limit at that point.

you put to many zeros in there my feeler gauge reads .102 MM on the two valves.it is the next size up from .10MM. If you think that is close enough I am putting this baby back together tonight and hoping that my new wires arrive tomorrow. Thanks for the help

Post edited by: dadams7161, at: 2007/06/08 00:51

Post edited by: dadams7161, at: 2007/06/08 00:53

Nope, no extra zeros in there, .002mm = .0001"

Try a .005" and if it won't fit then you are good to go. .10mm = .004" so .005" = .125mm

Better to loose than to tight, the clearance will decrease due to wear.

BTW, did you check the timing advancer to make sure it turns freely and is not stuck?

OK i was just looking at the metric readings that were on mine LOL. Yes the advancer is working properly I checked it to and lubed it up

Your valve clearances are fine. What type air cleaer do you have on the bike? What pipes?

what rpm are you turning at 55?

since you had a broken cable are you sure you were able to open the throttle all the way?

what does it feel like, is it like it is maxed out or does it shutter like its not getting enough fuel, poss a venting problem at the tank

wiredgeorge wrote:

Your valve clearances are fine. What type air cleaer do you have on the bike? What pipes?

I has a foam type air filter on it and the pipes are stock.

BSKZ650 wrote:

what rpm are you turning at 55?

since you had a broken cable are you sure you were able to open the throttle all the way?

what does it feel like, is it like it is maxed out or does it shutter like its not getting enough fuel, poss a venting problem at the tank

well before the new cluth I was at 4500 now it is around 3000 I believe it is very possible the throttle was not opening all the way I did not check just went ahead and bought a new cable and I just feels like it just looses power when you go up the smallest of a rise in the road it slows down,

just a couple more thoughts,
have you looked inside the exhast pipe to see if there is some restriction.

Have you tried to ride it with the gas cap open and taped down to see if it has a plugged vent

I am figuring you have a new gas filter and it is installed the right direction and you dont have any kinks in the line

Foam air filter? Hmmm, you may have added so much air, it is actually running out of gas. I would check the throttle cable first (good idea) and then look at the filter second. Does this foam filter require cleaning/reoiling?

just had a thought, does the bike pull hard thru the gears?