Kawasaki Versys Forum banner

Engine misfire at idle

4K views 7 replies 5 participants last post by  onewizard 
#1 · (Edited by Moderator)
G'day,

I've noticed lately the engine seems to cut out during idle??? I had a dealer top end re-build, de carbon, new vales & piston rings late last year. Iridium plugs are less than 2 years old + new stick coils. I serviced the air cleaner recently & checked the spark plug gap - all within spec. Idle speed is around 11,13000 & the misfire happens when the bike is hot. Running is fine, still goes like a rocket! Any ideas???
 
#2 ·
... Iridium plugs are less than 2 years old + new stick coils. I serviced the air cleaner recently & checked the spark plug gap - all within spec. Idle speed is around 11,13000 & the misfire happens when the bike is hot. Running is fine, still goes like a rocket! Any ideas???
How many MILES on your plugs? Just because they LOOK good and the gap is correct, doesn't mean that they ARE good. I assume your idle speed is 1,300rpm...?
 
#3 ·
Sounds like a possible TPS not set correctly, once off fast idle is off, if not set correctly it will lean out. Also if a sensor on the air box isn't plugged in it will do similar.
 
#4 ·
How many kms since the top end rebuild of two years ago? Your valve lash clearances should now be measured and adjusted, along with new spark plugs and a throttle body vacuum synchronization (done at 1,300 rpm idle). A compression check while you're in there could confirm that the rings are well seated and the new valves not leaking.
 
#7 ·
The symptoms you provided could very well indicate valves that are too tight. Like Invader said, the compression check would be more of a peace of mind thing but also could provide diagnostic help.

I would check the valves before taking it somewhere to chase after electrics, adjusting the valves is part of a "tune up" and critical for other diagnostic work. It's kinda the first order of business in this case.

The mileage since rebuild would seem to be a bit low for "too tight valves" but you do have to rule it out and who knows if they were set properly in the first place. Do you have a shim map form the rebuild indicating what clearances the valves were set at?

Edit to add: And as long as you are in there, do replace the spark plugs.
 
#8 ·
The booster plug adjust fuel by fooling air temperature. In actual fact your bike is a MK-2, that TPS setting is very important , several have done the vacuum hose link, I found it to be dumping excessive fuel while engine braking and went back to the original vacuum line. Invader is the one who first posted it.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top