Adjusted Throttle Stop Screw and can idle to around 2500rpm then dies

[Archania]

I have been trying very hard to get the '82 GS450T to idle properly. I was able to adjust the throttle stop screw and turn it on which makes it idle 5000rpm. I was able to adjust it down to around 2500-3000 rpm. When it goes past 2500rpm it quickly goes to 0 and stalls.
I have dumped the bowls and ran cleaner through the carbs several times already.
I also have the haynes service manual. I am stuck on what to do next.

Any help would be great. I have my class next weekend and trying very hard to get the bike ready to ride.

[SPARKSS]

I have been trying very hard to get the '82 GS450T to idle properly. I was able to adjust the throttle stop screw and turn it on which makes it idle 5000rpm. I was able to adjust it down to around 2500-3000 rpm. When it goes past 2500rpm it quickly goes to 0 and stalls.
I have dumped the bowls and ran cleaner through the carbs several times already.
I also have the haynes service manual. I am stuck on what to do next.

Any help would be great. I have my class next weekend and trying very hard to get the bike ready to ride.

Without knowing the history of your problem, I'll always verify basics first - confirm compression (if near-zero or low then you have to correct that first). I'll guess that the probable reason for the engine not being able to idle is lack of fuel in the mixture. Two usual culprits here The first thing I'd do, is get the thing running as best you can and, using an UNLIT propane torch (turned on) see if you can find air leaks between the carbs and the head (this will show up as an increase in rpm). If you don't find anything obvious here, try the same trick dumping the propane into the air box while seeing if you can then idle it down as you tried before (this, along with NOT finding any previous leaks) will let you know you have carb fuel problems otherwise (cleaning/setup per your manual).

I don't know your 82 450, but am thinking it has electronic ignition and, unless you have reason to know it was tampered with, is probably ok. The fact that it will rev up means the intake isn't restricted (plugged filter etc).

Alternatively to using a propane torch as described, you can spray a volitile oil such as WD40 giving similar results......just a little messy.

[KEITH KRAUSE]

Sounds to me like it's not drawing sufficient fuel when the throttle plates are at smaller openings/nearly closed positions.
First thing I think of is a clogged pilot circuit. Running cleaners through the carbs doesn't work well in most cases and can damage the inner rubber parts. Clogged carbs need to be taken apart and properly cleaned and also blown out with high pressure air if possible.

[bwringer]

Mystery potions won't do you any good -- sounds like your pilot circuit is clogged, as Keith mentioned.

Peruse the Carb Cleanup Series for CV carbs. You'll have a bit less to do since you only have two carbs. \\/

http://thegsresources.com/gs_carbrebuild.htm

All you'll need is a set of carb o-rings from Robert Barr:

http://cycleorings.com

These are sets of o-rings for the four-cylinder bikes, but you'll need only half.

You might need a couple of float bowl gaskets, but usually these can be re-used. Do NOT waste your money on crappy rebuild kits -- clean and re-use everything as outlined in the rebuild series.