torque problem GS 650 GT

[sahtlinurk]

Hi!

I got 1983 GS650 GT, from first to fourth gear, bike does fine. but with fifth gear on 5500 revs and upwards, there is actually no power left. in one second it revs and then again is like choked.. with other gears - nothing like this.
when I bought this bike, last owner had it restricted with smaller jets. and he just put the next size up in before i had it. too small jets?

Thanks,
Lauri.

[Big T]

Sounds possible

What size jets are in there now?

[sahtlinurk]

132.5 RD

that is written on main jets

Chrs.
Lauri

[waterman]

That seems pretty rich, 110 is standard. Are you running 4 into pipes and / or pod filters? IF so, I still think 132 is going to be plenty rich.

[Nessism]

Is the bike running on all four cylinders?

[sahtlinurk]

All four cylinders are working. I will try smaller jets.

Thanks,

Lauri

[chef1366]

Someone asked you if you had modified the motor with pod air filters and a 4-1. We could help you with a good base setting to your jetting if we knew what was or wasn't done.

[BassCliff]

Hey howdy hey!

Mr. sahtlinurk,

Let it be known that on this day you are hereby cordially and formally welcomed to the GSR Forum as a Junior Member in good standing with all the rights and privileges thereof. Please note that "good standing" implies pictures! :-D

Don't forget to check your valve clearances too. Thanks for joining us!

Thank you for your indulgence,

BassCliff
(The unofficial GSR greeter)

[spchips]

Are you running a fuel filter? It may be starving.

[sahtlinurk]

Hi Again

sry guys, as I am not english speaking i had to do some translation first.

well I have those K&N air filters( one per carb), installed by previous owner(s). four in one exc. pipes ( if you ment that) I just changed main jets back to original and the bike is not going over 4000 rev anyhow with or witout filters,( while driveing only ) so worse than before. valve clearances are all right.i do not use fuel filter, the one in the tank is checked..

any ideas? how to regulate the fuel mixture on these carbs?

Thanks,
Lauri

[Dave8338]

Have you pulled your spark plugs to check for the color? Blakc=rich or White=lean. Sounds like you may need to clean the carbs

[waterman]

What size are the original main jets that you have installed--the ones that prevent you from revving past 4000 rpms? If they are stock 110 and the other set is 132, with your setup, I think you need to find some that are around 115 or 117.5. Even then you may need to shim the needle to enrich mid rpms. Not an expert, just trying to help.

[sahtlinurk]

plugs are more like bright color than dark. it means that it really do not get as much fuel as needed. but why are those original ones does not work?? seems i have to go and get the ones ( 117) suggested.

Thanks,
Lauri

[Big T]

Lauri,

While the translation ino English is a drawback, keep plugging away and you'll get your answers.

We've established that:

1. You bike has a 4-1 header and pod air filters
2. It has been rejetted for #1

You will need jets larger than the 110 stock jets with pods and a header. To help us determine what the problem is, please confirm:

1. Did you just get this bike?
2. Was it running okay with the pods and header, then your problems began?
3. Are the air filters clean? Have you cleaned thm lately?
4. Was anything else changed on the motor that you haven't told us about?

[chef1366]

Does Dynojet make a kit for the 850?