synchronization help, bad throttle response!

[joezxr]

Im suffering with bad throttle response on my 2003 ZX6R (B1H) its always as if i pull the throttle back and it makes lots of noise but doesn't go anywhere, seems like its running out of sync!

Anyway so iv followed the procedure in the users manual to sync the throttle bodies, hooked up some gauges, warmed the bike up on the paddock stand, set the idle at 1300rpm, adjusted the center screw on the rail to match the highest vacuum of 1 and 2 to 3 and 4, then fiddled with the bypass screws until all the gauges dials are all in alignment with the same amount of vacuum...

BUT it now runs like absolute crap.

So to undo my apparent mistake, i literally just set the bypass screws all 2 1/2 turns out, and then adjusted the center screw on the rail until it sounded like it was idling okay and what do you know it runs a lot better and more responsive?

Now i am so confused, as far as i know this procedure is literally just to control how smooth the revs are and how smoothly it idles, not the fueling as it is fuel injected.... so why on earth am i having this problem?

can someone enlighten me on the proper way to sync throttle bodies because it seems the manual is absolute rubbish and im used to doing carbs!

[Robby]

Doing any carb or throttle body balancing is a bit like solving a maths problem. You need to have an idea of what you expect to do, and what you expect the result to be, before trying to solve it. If you blindly trust your method/instruments you can make it worse.

I think you cocked up on fitting the guages, most likely by not having a secure, air tight fit on one or more of the adapters. This gives you an inaccurate reading, and you adjust it based on that.

I've done the same using nylon adapters, which is why I always use brass ones. If you need more than one full turn to pull a throttle body into sync, or the readings keep drifting, check your tool.

[Stalk]

[orac]

I second checking your clutch. Also the way I have always balanced carbs is 1 and 2 then 3 and 4 then 2 and 3. All the gauges should be calibrated of the same carb before hand, it's normal to use number 1.
____________________
Current rides - 2016 Triumph Street Triple Rx, 1994 Suzuki Bandit 400 VM, TGB 204 Classic 125cc
"with nothing left to lose, there is everything to gain. It's not the size of the dog in the fight, it's the size of the fight in the dog"

[cb1rocket]

[orac]

It doesn't actually matter, it's so that the gauges read the same. There is normally a small valve to adjust each one, each gauge should be set the same amount of fluctuation, to much and they are unreadable to little and they are useless
____________________
Current rides - 2016 Triumph Street Triple Rx, 1994 Suzuki Bandit 400 VM, TGB 204 Classic 125cc
"with nothing left to lose, there is everything to gain. It's not the size of the dog in the fight, it's the size of the fight in the dog"