Help solve the mystery of my semi-working bike!

[mdonof02]

Greetings, thanks for taking a look. I hope you can help me out:

I have: 1982 Suzuki GS450T
-13,0000 miles, and just got back from a 2,500 miles trek

Problem: The bike starts up, but after say about 1 minute of idling, the engine begins to noticeably slow, but continues to run
- A little gas beings to drip from the over-flow tube from the carbs
- Upon putting it in first gear and trying to move, the bike begins to shudder, and usually turns off, unless I give more throttle, but then it labors into first. While riding, the big is laboring for sure, and is only running when I give it an excessive amount of throttle, then eventually shuts off.

Attempts at a solution: So far I have taken off the gas tank & looked at the pea-cock, and nothing seemed awry, but was clean as a whistle.
- Took the carbs off. I am no mechanic, so my over-view of the carbs was most likely cursory, but here's what I found: Unbelievably clean, and no gunk built up. I tweaked the float chamber heights a bit, since they were a little off. Looked over the jets, and no noticeable build up of dirt or any obstructions. Then put'em back on.
- Opened up the air-filter after use: A bit of gasoline built up, but no clogs/gunk anywhere that needed to be cleaned.


Okay, I hope I put enough information up here to give you some clue about where I am. Like I said, I'm not mechanic, and after looking threw my repair manuel, I'm all out of ideas. If anyone can offer some advice, I would greatly appreciate it.

Thanks

[Larry D]

What maintenence have you done ? Have you ever cleaned/dipped and rebuilt the carbs with new o-rings ? Is the petcock original ? Did you experience any problems on your trip ? How long has the bike sat since you've been back ?

I'm no mechanic either but, it's sounds as if you have either a petcock fail and/or one or more of the needle valves are allowing to carbs to overflow. It really doesn't matter what they look like on the outside...it's how they work internally that counts.

[koolaid_kid]

Sounds like the engine is loading up due to too much fuel. Possible suspects include incorrect float level, sticking, dirty or worn needle and seat. But with 130000 miles on it, what can you expect.
But seriously, when you changed the float level, did you raise the fluid in the bowl or lower it?

[Dave8338]

As Larry mentioned, it could also be a bad petcock adding to the problem.
Choke slides clean and set correctly?

[Big T]

C'mon guys - carb problems for sure, but

Valves adjusted when?

Running on both cylinders?