88 venture carb sync question

[twigg]

I have been wondering about the condition om my diaphrams, I don't see any pinholes but they are original and I am having carb problems. I have the airbox off and when I reach down with a tool to manually move the slides back one is very sluggish in coming back compared to the others. The other three move back fairly quickly. What is the normal movement?

Thanks.

 

Normally they slide back fairly quickly. If you have three returning in a similar manner, and one that is sluggish, then that one has a problem.

 

It could be any number of things .... Wear on the slide or body, a weak or broken spring, deposits on the slide, etc.

 

You might try moving the slide in and out with the top off and spring out to see if you feel any unusual resistance. Get everything spotlessly clean before you re-assemble.

 

When you check for holes use a bright flashlight behind the rubber, and stretch it very gently. Any holes will quickly become obvious.

 

That sticky slide will cause a number of symptoms ranging from an apparent flat-spot to an idle that struggles to return to normal. (Doesn't open fast enough to doesn't close fast enough).

[gscbertrand]

You might want to change the spark plug caps and wires then start using some sea foam.about 1/2 can. Run the bike as long as you can then let it sit for 24 hours. It can't hurt.

[Scudrunner]

I have changes plugs, caps and seafoam treatment. The bike was running pretty well a year ago but I couldn't pull enough vacumn to balance the carbs. Since then I probably did more harm playing with carb screws and now it won't come off choke, stalls with any throttle. Have read some good tips here like adjusting the throttle plates with a fine wie to get them in harmony. I did notice though that when I look at the inner throttle cable mounting bracket I see it flexing and until I can get in there I don't know if that is normal or not? Anyways, I have a new set of diaphrams ordered although I looked mine over before and didn't see any pinholes. I will pull the sluggish slide out, check it and clean it. What is a good lubricant for them? Can I spray them with silicone spray? We'll keep at it!