Signs of leaking throttle shaft seals???

Let me ask...did you by chance remove the butterflys and separate the carbs?

It sounds to me that your pilots aren't having any effect because you A. have a massive air leak between the carbs and the engine, the other side of the carbs doesn't matter nearly as much or B. the butterfly or butterflys are partially open. You MAY NOT be able to tell by looking it they are too far open.

It sounds exactly what I did when I reassembled a set a while back and had not set the butterflys correctly first. I took the rack back off, fixed my badly aligned butterfly and instantly, my idle dropped back to zero so I could set it with the set-screw.

but these other guys know a lot more then I do.....


jeff

 

Or all that dipping and pressure washing and dishwasher action has completely blown out/ruined the throttle shaft seals and there are now massive air leaks through there...

When you bench sync'ed, did you start off with the main idle (knob) screw IN far enough so that you still have some "adjustment" left to turn it DOWN further? It sounds like you may have run yourself out of adjustment.

Other possibilities, more remote but still possibilities:

When reinstalling the rack, did you accidentally trap the linkage under the fins on the back of the head so it CAN'T close all the way?

What method was used for setting the floats?

What method was used for bench sync? (What "gap gauge" did you use?)

Why in the name of all things holy would you have someone spraying WATER on it while trying to start it?

 

I used the business card strips Rick talked about and have had to bench sync like six times due to not changing the shaft seals and they failed. Using the card strips when I put them back on and start it it idles at about 2k. A turn or two of the idle screw it settles down to 11k. Right now mine will start and idle at 800 rpms without the idle screw touching. I did at one point have the intake boot screw hold the throttle open my son tightened that side so he turned the clamp where he could get to it better and it hung the throttle open.

 

I used the business card strips Rick talked about and have had to bench sync like six times due to not changing the shaft seals and they failed. Using the card strips when I put them back on and start it it idles at about 2k. A turn or two of the idle screw it settles down to 11k. Right now mine will start and idle at 800 rpms without the idle screw touching. I did at one point have the intake boot screw hold the throttle open my son tightened that side so he turned the clamp where he could get to it better and it hung the throttle open.

 

I haven't messed with the butterflys, or separated the carbs.

The bike ran before, never idled quite right but it certainly did not race up rpms.

Turning the idle screw one way or another really doesn't seem to make a difference.

I used the tube method for the floats.

I did use the strips of card like Rick mentions

I read somewhere about the water, I guess it is not the best of ideas. In any case, I did not think there would be any leaks.

If the bike idled before, what need would there be for a bench sync?

 

The funny thing is, I took the carbs off my KZ750 and cleaned and polished the bores, it does the EXACT same thing.

 

Sound like to me JeffK is on the right track that your butterfies are not closed, I like to use the K.I.S.S. method have you checked the adjustment on your throttle cable?

 

I have installed both racks without the throttle cable just to eliminate it as a source of the problem. It races when there is not throttle cable installed

 

Have you popped the clips and nylon washers off the outside of #1 and #4 and checked the throttle shaft seals you can see?

 

No, not yet

 

it sounds a lot like mine when the shaft seals started leaking

 

Put some 20/50 Oil in an Oil Can and put a few drops of Oil on the Shaft Seals with the Bike running off a small Tuning Tank.

See if the Revs come down.

Make sure the YICS Plugs are tight.
Measure the Vacuum on each Manifold and see it there is a tell-tale great disparity.
ColorTune. See if each Carb is able to be regulated (Color change) or if there is an obvious leak.

 

Well turns out the 750 carbs had one of the rack bars installed backwards (PO), causing the linkage to not snap where it should.

It idles so beautiful now


Hopefully the Maxim has a similiar issue

 

The things Previous Owners do can be simple mindned but wind-up costing you plenty.

I had a Bike come-by here where the PO used Automotive Radiator Hose Clamps on the Carb Manifolds.

The Automotive Clamps sliced through the Manifolds and ruined the Intakes.

Feel good about finding what the trouble was and be glad it didn't cost you anything to "fix".

 

Ugh.... POs are always a nightmare.

Fortunately mine was not nearly as expensive of a fix as yours Rick lol