help needed! bike won't rev

OK, so i've stripped the carb again, cleaned everything out that i can get at, i'm no expert on carbs, but to me the diaphragm seemed to be fitted ok, but just to be sure, I used a bit of silicon grease in the groove to make sure that it was seated correctly. Fires up fine but still having problem with revving, bike can be ridden, bet when I close the throttle (whilst bike is on the move) it sounds as if the engine wants to cut out, if I open the throttle the power delivery is not smooth, so bike takes off a bit quick. I took air filter off to see what happens when bike is revved, and the movement of the slide is a bit jerky, should it be smooth? Also checked for air leaks with WD40 but coulcn't find any. I am now baffled, looks like a trip to local harley dealer!

thanks

[kiwidave]

spark plugs soaked in petrol? oil?

Is there a VOES on this model? if the hose comes adrift between carb and switch, or has a hole, bike runs really rough

[eezyrider123]

Been standing 5 years ?
Sounds like sticking valves is a possibility.

spark plugs soaked in petrol? oil?

Is there a VOES on this model? if the hose comes adrift between carb and switch, or has a hole, bike runs really rough
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Yes there is a VOES on this model, although I dont fully understand what this does, Would appreciate if anyone could enlighten me on this.

[kiwidave]

the Vacuum Operated Advance Switch is connected by hose to the intake manifold. It monitors intake vacuum and sends a signal to the ignition module. The manifold pressure is then used to tell the module to advance the timing based on the engine load. It prevents detonation.

Here's a quick test to see if your VOES is good (picked this up off net years back, but it's rare for them to fail)

Get the engine *****warm and idling*** then use the KILL switch and shut it off. Get a long pair of needle-nose pliers, locate the hose running between the VOES and its carb port (far easier than unattaching the hose, these are usually bloody awkward to reach) clamp off the hose so the VOES can 't read anything, then restart the motor.

Get the idle speed steady, then release the hose and listen for a change in idle speed. It should be significant.

If you don’t hear any idle speed change, then test the switch further. At idle, it should have less than one ohm resistance to ground. If it has more resistance, replace it.

Check also the ground wire going from the VOES to your frame (often mounted to a stud on the edge of cylinder head), and also, the wire coming from your ignition module to the VOES.

these checks are pretty cheap

Thanks for the help guys, and thanks kiwidave for the info on the VOES, I always wondered what the hell that was for. Anyway I've finally solved the problem, the accellerator pump was blocked! I was so busy checking the diaphragm and main jets etc, that I didn't check if the accellerator pump was actually squirting fuel into the venturi. At least I've learnt alot about a sporty carb! So it's off to get an mot tomorrow. thanks again, great forum