Motorcycle Repair: KZ1000 - losing top end, yamaha venture royale, sta bil fuel stabilizer

Question
You were very helpful to me several months ago so I thought I'd ask for your assistance again.

I have a 77 Kawasaki KZ1000 B1 LTD. I got the bike out of the shop a couple of weeks ago after having the carbs cleaned and the timing reset. It ran fine when it left the shop. I only ride it once or twice a week in winter. Two days ago I took it out for a spin and seem to have lost my top end. The engine misses at 3000 RPM and above and under acceleration. Any ideas about what might have changed since I got the bike back? The only thing I have done differently is to add a little Sta-Bil fuel stabilizer for the winter months.

I also noticed some slow gas seepage from 2 of the carburetor float bowls, which probably just means new gaskets. I guess I'm wondering if I have a leg to stand on if I go back to the same shop! Thanks.

Arthur LeJeune
alejeune@mvp-av.com  

Answer
Hi Arthur,

I remember your name thru association with (Marines-Camp LeJuene).

It's important to add Sta-Bil in proper amounts or the engine may run poorly. I once had to clean a Yamaha Venture Royale's carbs after the owner added Sta-Bil. If a little is good, alot must do wonders, he thought. Follow labeling instructions carefully.

What do spark plugs tell you? Remove the plugs and read their conditions.

Drain and add fresh premium gas and see if the problem clears up or improves. May need to clean spark plugs, too.

The leaking carbs may be gaskets. If so, try tightening bowl screws. Don't use silicone gasket sealers on float bowls. Silicone breaks down in fuel and clogs jets. Be certain the overflow tubes are not the source of the leaks. If so, the carbs will need to come off and adjustments made.

I would contact the shop and discuss the running condition of the MC as last resort. Be respectful for best results. Flaming arrows work best when they blow you off. Puts distance between you and the scene. :)

Mark Shively
www.fop104.com

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