Hi-
Maybe someone can help. I just re-assembled my fuel system (removed and cleaned both carbs, unclogged jets, drilled out brass plugs which hide fuel mixture screws and added fuel filters below the tank)...
today it starts up ok, but has poor throttle (hesitation). I haven't let it run very long, but I did spray carb/choke cleaner up into the area above the carbs, and the engine level dropped when I did.

I removed the tank again and ran it, and sprayed the stuff around the carbs again. Now it doesn't drop,
it runs fine. Makes no sense. But still has hesitation in the throttle. I've looked for an air leak and can't detect any.
I removed the air cleaner and (it's not too bad) the engine runs the same with or without it.
Vacuum lines not pinched. All connections tight. I haven't played with the mixture screws yet.
New plugs. Hose connections ok.

(Before all this, it used to run only with choke on, it idled poorly, had occasional misfire, lean plugs,
then one plug started becoming fouled... that's when I took it all apart)

What causes the engine level to drop when carb cleaner is sprayed on the carbs? I always thought it would go UP, not down  if there was an air leak.

Anyway, I'll run it some more; I expect the occasional misfire to return. (it always did, about a week or two after shop servicing, then it would go away again when I dragged the bike back to them).

I hope I'm making sense. Time for a drink!

95 model 500e

steve

Vacuum leak.  That's pretty much the test for vacuum leaks is to spray something (I use starting fluid) around possible locations where the carb could be sucking air.  The vacuum caps on top of the carb were probably loose.  I'm going to replace mine because of that same issue.

I did open the caps to check them, and I replaced one missing tiny o-ring which was missing. But they are  tight. Anyway, I may repost this whole thing because the problem has changed. It idles fine, and spraying makes no change.

One cylinder isn't firing at all, at idle. That explains the slow throttle/acceleration.  It was firing before I took everything apart, just not very well. But now, not at all. So I must've missed something when I cleaned the left carb. I'm tempted to re-post this new problem, after I search the archives first.

Thanks for the tip. I will re-check the vacuum diaphram tops again, and probably replace the mis-matched screws. (I noticed that someone had been inside these carbs A LOT.)

Steve

I've had my carbs off countless (or at least uncounted) times.  I finally got it right.  The factory service manual is good for learning how it works and what you need to clean/check for proper operation. 

The first dozen or so times I did rejets on my Shadow, putting the vacuum diaphragms in was a pain.  Even tried putting grease around the groove they fit into.
The next several dozen times, were easier- no grease, just push the cap down onto the spring gently and uniformly, it will seat the diaphragms into the grooves, watch the last 1/8 inch by sighting along the edge of caps, you will see if the diaphragms are seated correctly.
Although a Shadow, same principle as other CV carbs.

When I looked at the vacuum diaphrams, one seated nicely but the other one was all blown out
and it was difficult to fit it back into its groove. But I did.

Maybe it popped loose when I (carefully) replaced the cap. Wasn't sure if I could get a new one
without buying a whole new rebuild kit, and even then would it contain the big ol' rubber diaphram?

thanks for the tip.

s

Rebuild kits typically contain o-rings and needle valves.  Not a bad idea, but not a diaphragm.  You can get most parts from the dealer, or from an online dealer like bikebandit.