rpm's

[craig196]

Just trying to figure out whats wrong. When I throttle up it takes awhile to idle back down, also on it's own it rev's up now and then. I already rebuilt the carbs. Is there a liquid gasket I need to put on the rubber seals that connect the carbs. to the head. I thought maybe I'm getting a vacume leak at those spots. I have a 82 GS450T if this helps. Thanks, Craig

[Nessism]

GS motorcycle school now in session.

Lesson numer one (1).

Large O-rings trapped between the cylinder head and the rubber carb boots dry out allowing them to leak - suck air "in" actually. This will lead to an inconsistant idle (usually high). Sometimes the boots themselves dry out as well so you should inspect them carefully after taking them off.

Schools out.

Good luck.

[craig196]

I did replace the O rings and the rubber boots seem soft. When I took them off there seem to be something on them to help seal them. I just ordered new boots just in case there could be a small crack that I don't see. I'm new at this and any help is greatly appreciated. Thanks, Craig

[chef1366]

Where did you get the o-rings? Sounds like they were the wrong size. We are talking abot the o-rings between the intake boots and the head, right?

[fgh]

Sounds like you need to synch the carbs. I would think any crack large enough to cause your problem would have been visable. Every time you take the carbs off coat the boots with silicone grease. Here in the US I get it a Ace Hardware. Comes in a small tub, 1 to 2 oz. LOL!

[craig196]

I bought the O rings from Bike Bandit. They are the right size. We are talking about the same thing.

[jimcor]

Craig, just because you cleaned the carbs once doesn't mean you got everything clean. You wouldn't be the first guy that had to re-clean carbs a second or third time. Did you replace th O rings in the carb? I'm not familiar with 450 carbs, but I'll bet Robert Barr's kit will have the rings in it that will work in your bike.

www.cycleorings.com

[Dave8338]

I bought the O rings from Bike Bandit. They are the right size. We are talking about the same thing.

Sounds like you got that covered...just to cover the bases, I will mention a valve lash check and then carb synch. A bench synch is good enough to get things going however, once you have the bike up and running, and after the valves have been set, a true carb synch will cure most performance issues unless something is amiss somewhere else.

It can be a bit frustrating...but hang in there. To my knowledge, there has not been a bike yet, that won't challenge one's mechanical abilities, from time to time. At least you've found the right spot to get you through the project. And when you're done...and after a ride or two, you'll forget about all the fun you had getting it done right.

[craig196]

I replaced the O rings with the O ring kit. I also have a problem with the right carb leaking fuel out of the over flow tube. What do you use to gage the float tubes and where can you buy this tool? I ran the bike for a few days and everything was fine and it all started. I bought the bike for $100.00 It looks like it just came out of the show room. If I can only get it to run with out any problems.

[fgh]

Well the tool to set the float costs money and can probably be had on line. It is adjustable so you can use it to set any float. I've got two bikes and don't want to spend the money. SOOOO! When you set the float you adjust the tang on the float so that it just touches the needle valve when the bottom of the float is the specified distance from the carb body. Now lets say you spec is the same as mine 15.5mm. Take 15.5 divide by 25.4 and multiply by 16 and you get 9.7632. So in inches your setting is 5/8". Be as precise as you can. Get a piece of that heavy paper that is used to package stuff for retail sales. Cut out a square 2" by 2". From that square cut a corner out that is 5/8" by 5/8". When adjusting your float NEVER EVER FORCE THE VALVE INTO THE SEAT. Turn your carb upside down with the float bowl off. Raise the float off the valve and with the cut out corner resting on the float bottom lower the float until the tang just touches the valve. Since your leaking fuel out the overflow you will see that the paper touches the carb body before the tang touches the needle if your problem is an improper setting. If in fact the tang doesn't touch place something under the tang and bend it GENTLY until it does.
With this said it maybe debris in the needle and seat. On Suzk’s the pin that holds the float on is pressed into one of the posts. Before you try to adjust the setting take a small nail or something and tap the pin out. You have to tap the pressed in side inwards. Check for debris in the seat or on the needle and look carefully for damage to both parts. If either are damaged replace them both. That’s about it. Best of Luck!

[craig196]

fgh, I will try what you said, I really appreciate the help and that goes for everyone. Thanks, Craig

[robertbarr]

When I throttle up it takes awhile to idle back down, also on it's own it rev's up now and then.

Not sure about twins -- all I've ever worked on (much) are I-4's. However, on a 4-banger, this is a symptom of carbs that are out of sync, or an intake leak. We've (well, you've) eliminated the intake leak, so I'd look at sync. Should be super-easy with just 2 carbs.

[kurifu]

Your carbs have spings above the slides, make sure they are still there, with your bike off use something like a popsicle stuick to push the slides up, do they return when you take the stick out? If not could mean they are dirty and/or the springs up top are missing.

[craig196]

Right now I'm cleaning the right carb again and I ordered some parts just to be sure everything is new when I put it back together. My carbs are super clean. They look like I just bought them new. Nothing is sticking. When I get them back together I will try to Sync. them. I will let you all know how things are going. Thanks again, Craig