Running too lean

[jordraatt]

Hi folks!

I have a GS650M Katana 1981..

After replacing the air-filter with 4 individual KN power-filters, the motorcycle was running too lean.. So i bought a carb-jet kit and changed the main jets and put in some spacers on the needles.. They told me that this kit was big enough for my little modification..

After installing the new carb-kit the engine is still running lean.. I haven't done any adjustments on the carbs.. What shall i do??

[MisterCinders]

Any other mods to the bike (e.g., pipes)?

What jet kit did you use? For pods and 4-1, most start with a DynoJet Stage 3.

Where are you getting the lean symptoms - idle, mid-throttle, WOT?

[AJ]

I don't know which jet kit you bought, but I have the needle raised two full clips from the DynaJet recommended settings and I still think it's too lean in the mid-to-upper ranges. Might be going for a larger main jet.

If you haven't read it, I think this is the best "how to" tutorial for tuning CV carbs:

http://www.factorypro.com/tech/carbtune,CV,high_rpm_engines.html

[jordraatt]

Any other mods to the bike (e.g., pipes)?

What jet kit did you use? For pods and 4-1, most start with a DynoJet Stage 3.

Where are you getting the lean symptoms - idle, mid-throttle, WOT?

i have replaced the rear mufflers with straight thru..
the jet kit comes from a company called SigmaRacing.. i think it is stage 3, i mentioned all my modifications.. main jets are 2x135 and 2x137,5..

the lean symptoms are in the mid-throttle.. it runs fine on idle..

[MisterCinders]

Mid-throttle mixture comes from the needle setting. Raise your needle a notch and see if that helps.

[jordraatt]

yes, i read that too.. so i'm gonna try so.. it said 2 shims in the instructions, but i'm gonna try raising it even more

[tkent02]

Did the jet needles come with the jet kit or are you using the stock needle?

[tom203]

Did the jet needles come with the jet kit or are you using the stock needle?

I hope he answers this correctly!

[jordraatt]

there were no jet needles in the kit, and the instructions said that i should use the original ones, so i am using the stock ones

[jordraatt]

now i tried to raise the needle a little, but nothing changed.. goes well on low RPM, but as soon as i turn the throttle it dies out..

[jordraatt]

any ideas anyone??

[tom203]

now i tried to raise the needle a little, but nothing changed.. goes well on low RPM, but as soon as i turn the throttle it dies out..

The stock needle worked well with stock airbox/exhaust setup, but as you are discovering, things get messy with pods. Folks here stress getting the dynojet kit which has its own needle- this makes for a happy marriage in the mid range .

[jordraatt]

so you sugest that i get dynojet needles instead of the originals??

i think it's strange that the manufacturer of my jet-kit didn't mention anything about that

[tom203]

so you sugest that i get dynojet needles instead of the originals??

i think it's strange that the manufacturer of my jet-kit didn't mention anything about that

No. you need the kit, cuz the needle "mates" with the other dynojet parts. check this link out.... the stuff is designed to work in harmony

http://www.z1enterprises.com/detail.aspx?ID=4059

[jordraatt]

okey, thank you very much.. i've ordered this kit now, looks much more "pro" than the other kit i ordered.. much more parts in this one..