Stumbling Bird

[Mr.XX]

For the Carbed and Carb savvy,

I recently had a dynojet kit installed on my 97 bird

it runs great except it stumbles when I first crack the throttle

otherwise it works good throttle response is much improved everywhere else.

I dont have a great holeshot to start with (leave the jokes in the pub :roll: ) but that is where the stuble shows up

any Ideas ?

[ststricker]

Have you had the carbs synch'ed lately? Just an idea. I had mine done last year and it made a noticeable difference in the idle and initial throttle response.

[Mr.XX]

yeah I had all that done when I put the jet kit in

[Northman]

Too rich.

My buddy's did this when we installed his jet kit, and to me it felt like a lean stumble.

So, we disassembled the bike again, and raised the needles one notch. Couldn't tell much difference, so raised them another notch, when the stumble got really bad. Took it apart for the third time, and lowered the needles as low as they could go but left the washer under the clip.

It was pretty good, but I still want to remove the washer and try it once more.

Try lowering your needles one notch and see what happens.

[Mr.XX]

thanks North,

I'll try that...I think I'll put the K&N back in first see if this makes a difference....I took it out because the bike ran like crap when stock with the K&N in... now that I have jetted it and put the slipons on maybe the increased airflow will take away the rich condition....

I really like the way it runs now except for the dead stop/closed throttle stumble everywhere else it is very smooth ... the light switch throttle response is gone.

[Northman]

Adding the K&N should definitely make a difference for you, and you can use it to help tune, also.

If the stumble gets better, or leaves altogether, you know for sure it was too rich.

If it gets worse, then it's a lean condition.

[Andy1100]

Rule of thumb I was told, was stumble under load=rich

problems with no load=lean

Then there's the ol, try it with the choke slightly on better=lean worse=rich.

Duct tape on the air filter.

and it goes on and on.

Once you figure out rich or lean, determine where in rpms and throttle position you are to figure out what to make the adjustment to. Pilot, main, needle. Looks like you've got that straight already.

When you first crack it. Crack it hard or smooth? Throttle position?

Sounds like you could probably take care of it with just an Idle mixture adj. Twist em in an 1/8 and try it.

Definately put the K&N in FIRST, and go from there.

[rickrad]

pm spEEdfrEEk (TJ) if you are still having problems, he REALLY knows his shit about carbed birds. He bought a carbed bird because he likes to tinker with and tune carbs!

[Mr.XX]

Thanks, Andy and Rick ect...

I will prob put the K&N in tomorrow

I am taking her to the shop to have a chain and sprockets installed

16t front and cool air should make for some fun.

[DaveK]

Ralph..Sell it !