Dear MOby,

Help! My ’97 ZX-6R Kawasaki is running rough. Somebody said it sound like it’s only running on three cylinders. I replaced all four spark plugs, and all the wires and plug caps look fine, but it still sounds sputtery and sad. Another friend suggested maybe a plugged jet in one carburetor? Do I need to take all the carburetors apart or what? How can I tell which cylinder is the one that’s “missing”?

Raggedy Andy
Tucson, AZ


Dear Ragged,

Yes, if all the plugs are firing but one cylinder (or two) isn’t, it’s probably a fuel delivery problem and probably something is wrong in one carburetor. In a perfect world you’d rebuild all four of them (since you’ll have to take all four off in one chunk anyway), but in our world, why take all four apart if you don’t have to?

Here’s a trick straight from the 1980 Kaz Yoshima/ Ontario Moto-Tech playbook: Fill a squirt bottle with water, start the engine up, and spray each head pipe with a squirt. The water will flash into steam instantly on the “live” cylinders, and it’ll drip onto the ground on the dead one(s). That cylinder’s your problem.

And if it’s not that carburetor, when’s the last time you checked your valve clearances? Too-tight ones can also cause a misfire. Good luck and happy squirting.


Direct your motorcycle-related questions to AskMoAnything@motorcycle.com, though some say we’re better at non-motorcycle-related ones…

 

  • JMDonald

    Sounds like a plan. They have some nice stuff.

  • Bruce Steever

    They’ve got a deep, deep, deeeep hole to dig out of, for sure, but i’ll always have a soft spot for the brand. Good luck Suzuki!

  • Michael Mccormick

    Hope they have the budget to develope truly new bikes and not just parts bin specials. Just don’t think they have the scale to compete with Honda and Yamaha. At least for now with the cheap yen, they may pull it off. In the long run they need to move some production to Thailand or India like Honda, Triumph, KTM, and even Harley. Loved their X-6, Katana models in the eighties, the 16 valve GS series, the original GSX-R’s, and the TL1000S and R.

  • Alclab Ventek

    They’ve always made great bikes and the GSX-R have been great (mostly) throughout the years, they just need a little more development in their electronics package (I know I don’ miss it, but in this day and age, they need it to be competitive), which will probably be aided by their MotoGP program; and they really need to work on some new designs for their sportbikes.

  • Jimmy Z

    What they need to do, unfortunately, is establish themselves in the Bagger market. They make some nice V-Twins but don’t make a faired, overweight model with cruise control. While they build good sportbikes and dual purpose machines they have no presence. People need to see them on the street more.

  • SteveSweetz

    Can I post a question here without having to email? Anyway:

    Yamaha recommends throttle body syncs every 4000 miles on all their “CP3” engine bikes (FZ-09 and derivatives). I’ve got an FJ-09 and it’s a huge pain doing this due to the extra body work on my bike. Does this seem overly frequent to anyone else? Realistically speaking, what’s the worst that can happen if the throttles are a little out of sync?

    • Jon Jones

      Not needed at all. Running well? Nice idle? Then all is good. No harm if it’s off slightly. And it’s not. When I have checked throttle body synch, it’s always damn close if not perfect

      Great post, by the way. As a lifetime motorbike mechanic, I see more harm done doing unneeded maintenance than any potential perceived benefit. I’m good, but lazy. Lazy in a good way. I fix what’s needed. I don’t go looking for issues that aren’t there.

      Most newer bikes just need the basics; Tire pressure, occasional chain love, quality oil and filter from time-to-time, etc. Following the factory maintenance chart on certain items can often separate fools from their money.

      And good article, also. I use a non-contact thermometer regularly to pinpoint lazy cylinders. Wonderful and affordable tool.