More problems. **** | GTAMotorcycle.com

More problems. ****

brockmx

brockmx

Well-known member
Was riding to work today and my zx9 was running ok sounded like vales need done and then all of a sudden started to sound like an old pos car with no power. No exhaust leak. I'm guessing the valves are so far out that one is stuck open now. I don't know what I should start with.
 
If you lost power, you've probably broken a valve.

Don't run the bike any more, you're causing more damage every time it runs and it will stop running completely very shortly.
 
How much more involved is a valve replacement versus the valve adjustment I was going to do
 
brockmx said:
How much more involved is a valve replacement versus the valve adjustment I was going to do
Click to expand...

depends...new valves need to be seated if your head isn't done. Or you'll need a new head, head gaskets etc etc etc....

Motor on a work bench would be the best thing to go about business

looking at atlest 10hours or shop labour if not more, 10hours x $85/h = $850 + PARTS + machining work
 
Could it just be an exhaust valve stuck open I wasn't even going hard I was short shifting to conserve fuel
 
Took a real look.
4ac609e0-2690-b736.jpg


Looks like it was cut with a plasma cutter or something. It's a clean break
 
this is tricky. If a valve broke you'd DEFINITELY hear that clanging off the piston while running. If you DIDNT hear that then I doubt it's a broken valve. You could do a compression test to see if you've actually lost compression and in that case I'd say take it in. If you've ridden it already after the proposed break then a few more cranks for a compression test wont do much more damage if any at all in my opinion (I take no responsibility if it indeed does cause more damage, fire, loss of life, dismemberment, loss of vision or hearing :)).
I wouldn't expect that exhaust leak to cause a huge loss in power either, but anything is possible.
 
Actually, I would expect that exhaust leak to cause a HUGE loss in power. High-performance engines rely on the pulsations in the exhaust system to help the engine breathe. At least fixing this doesn't involve an engine rebuild, and it's an excuse to replace that stock exhaust header with a high-performance one!
 
It wasnt like I heard something break it was just getting rougher and rougher the farther I went. 2 headers are 100% broken. I'm trying to think of a quick fix to get me home though. Any suggestions?
 
And my bike has been popping and craking a lot on decel lately. I just assumed it was poor jetting that I will fix. This may explain it though
 
These bikes are notorious for stumble/hesitation at 2000rpm. Go to zx9r net to see how many threads there are.

I have a spare header you can borrow for the short term, usual fee of large dd from timmies is applicable.
 
My buddy is going to weld then back together I just thought maybe tin foil wrapped around thick and a clamp so it doesn't sound like a 1990 Buick with no headers
 
Welded the pipe back together and got rid of the popping, power loss, and retarded sound. Next is valve adjustment. I'm glad it's not a valve replacement.
 
If you want to take a trip to Huntsville, I've got a header pipe off a 98 zx9r you can have. Its in good shape and taking up space.
 
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