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Discussion Starter #1
:pepper: I pulled my carbs out today.First time ever.I have an '86 with 20,000 miles on it.Everything looked good.The only thing I found,was that the coaster richening diaphram was worn and a little frayed on rear carb.It had some small tear's on it.My question is,with this diaphram worn,what would it do to the performance of the engine? I've had some problems,and Im just wondering if this was the culprit. Thanks, Steve:doh:
 

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I am not going to be able to tell you the problem, but I can tell you the folks who are going to help you will need to know more... what kind of problems are you having? Is this a new bike to you? Did you just get it? Did it sit for a long time without being ridden? Have you replaced the battery with a M/F one? Did you run seafoam through it? What kind of gas are you using? What kind of Oil? All these questions will help everyone here diagnose the culprit, but first and foremost they need to know what the problem was that prompted you to pull the carbs in the first place.

Just my .02 cents... now I will let the real wrenches help you... good luck!:smiley_th
 

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Discussion Starter #3
One time,while sitting overnight,the front carb flooded out on garage floor.I did not have the petcock turned to prime.Another time,it idled like only one cylinder was working.I ran seafoam through it and it ran good for a couple of days then started acting up when I would idle down from high speeds. I then ran carb cleaner through drain hole and it ran fantastic for about 30 miles.When I got home,I shut it off,then took off and it started bogging down like it was flooded or something.While idling,if I lean the bike to the right,it idles faster.[/U Now,lately, it acts like the rear carb is not getting gas.If I turn the petcock to prime for a few seconds,it starts running good.Thats why I decided to pull the carbs and find out whats happening.
 

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great start, now how long have you had the bike? did you get it used or new? has it ever sat over a long period of time with a half full gas tank?

I am really out of my depth here, HIZZO, CC, Cegodsey are you listening, this poor guy needs help!

kait
 

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Discussion Starter #5
I've had the bike for about 8 months.It did sit for a few years with the previous owner.My tank has some rust in it,also I question my petcock.After sitting for so long,I turned the petcock to reserve and wander if the diaphram is messed up.I am going to clean the tank and check out the petcock before putting everything back together.
 

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HAWK
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Sounds like you are on the right track, I would replace the diaphram. That can cause flooding and poor running. Yes make sure there is no junk in the tank or in the petcock. Can cause the float to be plugged or the jets to get cloged. If sea foam helped sounds like dirty gas from sitting. Varnish can build up break off and cause problems. Take your time with the carbs, a small mistake or loose jet can cause you alot of problems down the road. I would reed up on the Vulcan Verses also just to keep up on maintinance.
Keep us informed.
 

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If I were you, I'd drain the gas, take the tank off, take the lid and the petcock off, and all other hardware, and clean the tank out. Fergy or Nachos4life are a couple of the tank cleaning/recoating experts. There's also a write-up in the verses. Tankist is eventually going to coat the inside with zinc, using the method in the verses. You should do this before you do much of anything else, to eliminate any problems upstream that a piece of rust may cause you later.
 

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Let's see if we can figure this out. When you coast, the vacuum drops because you are no longer wanting to draw air into the system via the butterfly valve. So then the diaphragm must work to let more fuel into the intake to prevent green house gases when the vacuum is low. Now, by looking at the parts diagram, if the diaphragm is frayed, then wherever the vacuum is coming from will start sucking gas instead of air. With this info, I'd have to guess that when you are accelerating, or keeping the speed the same, the bike is running rich, as if it had the choke on. Am I close?

But then, I could be wrong.
 

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ssmendez said:
One time,while sitting overnight,the front carb flooded out on garage floor.I did not have the petcock turned to prime.Another time,it idled like only one cylinder was working.I ran seafoam through it and it ran good for a couple of days then started acting up when I would idle down from high speeds. I then ran carb cleaner through drain hole and it ran fantastic for about 30 miles.When I got home,I shut it off,then took off and it started bogging down like it was flooded or something.While idling,if I lean the bike to the right,it idles faster.[/U Now,lately, it acts like the rear carb is not getting gas.If I turn the petcock to prime for a few seconds,it starts running good.Thats why I decided to pull the carbs and find out whats happening.


i had a carb that was leaking gas. i ran seafoam and it helped but then it must've knocked some junk into the system which then caused poor running but i kept riding for a day or so and it worked its way through. no carb probs since. knock on wood.
 
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