Kawasaki Z125 Forum banner
1 - 7 of 7 Posts

·
Registered
Joined
·
34 Posts
Discussion Starter · #1 ·
Alright guys. I've got the TB 194cc big bore kit installed and the bike doesnt want to idle anymore. I've put about 300 miles on it since I've done everything. Had it dyno'd and tuned. Ran perfect until a little bit ago. I've got a ninja 300 injector with a NGK CR8HIX spark plug. I threw 100 octane in there to see if that helped at all. It didnt. Anyone else have a problem like this? Thanks!
 

·
Registered
Joined
·
177 Posts
Check your compression and if it is lower than expected, check your valve clearance. We are running the TB V2 head on our race bike and it has had the valves tighten up after some serious high RPM outings so it might be worth a look. If there is still clearance then it might be worth pulling off the head to have a look inside since something has changed. Any idea if it got really hot at one time? Do you have an oil cooler on it?

BTW, how hard is it to start that monster? Do you have a decompressor on it? Does it crank over slowly?
 

·
Registered
Joined
·
34 Posts
Discussion Starter · #5 ·
Check your compression and if it is lower than expected, check your valve clearance. We are running the TB V2 head on our race bike and it has had the valves tighten up after some serious high RPM outings so it might be worth a look. If there is still clearance then it might be worth pulling off the head to have a look inside since something has changed. Any idea if it got really hot at one time? Do you have an oil cooler on it?

BTW, how hard is it to start that monster? Do you have a decompressor on it? Does it crank over slowly?
It may have gotten hot on one ride, but not to the point where it would cause damage. Yes, I have a takegawa oil cooler on it. I can bump start it just fine. I pulled the spark plug out yesterday and it's running a little rich. Gonna replace it and throw it back up on the dyno with the 100 octane to see if that helps it.

And yes, it's very hard to start it some times. I've got the tb 2v decomp head. Still cranks over slowly. Sometimes takes a couple tries before she fires.
 

·
Registered
Joined
·
875 Posts
I've got the tb 2v decomp head. Still cranks over slowly.

Can you provide some more information about the decomp head? Is it an automatic or manual decompression? I haven't been able to get any real information from any of the Z125 vendors. I plan on going with the 143 kit and I keep getting told that decomp isn't needed... but if it's only a few extra $ to keep automatic decomp, it seems like a no brainer... especially since I have heard a couple reports of broken starting gears...
 

·
Registered
Joined
·
34 Posts
Discussion Starter · #7 ·
Can you provide some more information about the decomp head? Is it an automatic or manual decompression? I haven't been able to get any real information from any of the Z125 vendors. I plan on going with the 143 kit and I keep getting told that decomp isn't needed... but if it's only a few extra $ to keep automatic decomp, it seems like a no brainer... especially since I have heard a couple reports of broken starting gears...
It's a manual decomp. Push the "button" in just before starting. Then once it fires it pushes it out. If I try to start with it out, it wont ever start. I also put the thinnest base gasket on, so that gives me a little more compression. I know there are some auto decomp cam sprockets, but idk how well those actually work. I've only been able to find the manual decomp head on the 178/194cc kits tho. And that's on ebay. Cant find it on TB website. The pic shows what it looks like. That red button is the decomp button
 

Attachments

1 - 7 of 7 Posts
Top