I have lost all power between 2k - 4k rpm.  Pulled apart the carbs a verified all is clean and floats are correct.

Any suggestions? Ignition problem?

Wow- when did the GS ever have power under 4,000 rmp?

What year is the bike? are there any mods on it?  Milage?

I don't know what you mean by lost all power.  Does that mean it had power before and you have recently noticed a difference?  The average GS is useless under 5,000 rpms.  

$15 will get you a 14t sprocket.  Advance the ignition.  Those are the cheapest/easiest ways to gain on the bottom end.

my gs pull ok from 2 to 4k, not great, but enought for commuting, check your air filter... have you changed your gas brand?  hit it with some carb cleaner

Welcome!

Our bikes typically don't have much power between 2-4k, but you're stating that you lost all power in that area. Is your bike stock? When was the last valve adjustment done?

good call scratch

1999 GS 500E 7500km.  The bike was in storage all winter.  It was running excellent when it was put away.

The bike has a dynojet stage 1 w/ a Hindle exhaust and K&N air filter.

Last year it was very quick, but something has happened.  Very rough idle with a 50% reduction in power at low-mid rpm range.

Does it rev up smoothly or do you have to feather the throttle? Try checking the wires from the ignition module to the coils. Corroded connections can lead to intermittent spark. New plugs never hurt.

Did you just get it out of strorage?  How many tanks of gas have you put through it?  Have you changed the oil since getting it out of storage?

Yeah if it's got the same gas as it did when you put it away, it could be as simple as that.  Did you put some Sta-bil in it before putting it away?

jeff

No power in 2K-4K? Not my GS.

I can shift to 6th gear, and at 3KRPM I can open GAS and the bike
pulls hard till 7K, then it will not go beyond, need to shift 5th, and
it will pull very little to 8K or 9K.

Any way to merge 2 engines?
(Stock jetting 120's and 37.5, Thunder competition exhaust, 2 washers
under the needle).

Marc.

Marc-

Members in the past have described similar problems and have attributed them to valves being out of spec.  Search for posts on JohnLA and Richard
from Utah.
I had a similiar problem that had more to do with throttle possition and not being able to pull enough gas.  I ran a straight, short gas line to the carbs and my problem went away.

Thanks for your help folks!

Same gas as last year - however, I did use stabilizer.

I will try:

New plugs.
Clean/check wires and connectors.
New gas.
Valves - clearance/compression check.
New gas line direct to carbs.

It's always a good idea to hit a problem with one fix at a time.  I'd start with a couple tanks of fresh gas with some sort of additive/cleaner.

Then move to the plugs/wires and end with the valves.

Thankyou Hi-T

Valves should be OK, since it's 4000Km since last valve job.
But I may have valve seats or valve seals out of specs.

I've ordered from Srinath 125 and 40 jets, and a vacuum gauge.

Planning full engine diagnostics (will take photos) and a carburetor
work again.