Low RPM Jerk

[gsatterw]

So my bike sat for too long and my carbs were really, really gummed up with what appeared to be some copper oxide of sorts was caking the jets.

I cleaned them the best I could and slapped it back together.

Just took er for a spin. It idles perfectly fine, but the bike jerks and stumbles all the way from idle to about 6.5k rpm's. Perhaps "buck" is the correct term. The bike halls ass from 6.5-redline. So I can't really ride the bike slow/parking lot speeds.

I tested it out in neutral too and does the same thing - rmp's stumble around until it hits 6.5 or so and then takes off.

Think I have more crud in my mid jets?

Carbs have been tinkered with. K&N exhaust, Lunchbox air filter, 22.5, 65, 145 jets, 3 turns out on air screws.

[dk31285]

What shape is your chain in?  I'm replacing mine very soon (just got it in the mail yesterday) and I experience something very similar to what you describe.  I know for a fact that my chain has at least 3 "frozen" links. 

[gsatterw]

Not the chain. Exhibits same behavior in neutral.

[Slack]

Are you using fresh gas? or old stuff that was sitting in the tank?
Was it completely warmed up?

[gsatterw]

Gas is certainly crap. But if it was too far gone, I wouldn't expect the bike to run so well at a higher throttle opening.

Bike was warmed up.

[The Buddha]

22.5 and 65 are too rich - most people do 20 and 65 with 147.5.
The fact that you're running fine with 145 up high means you're too rich on the others.
Try this experiment.
Don't touch a thing, if you have the stock 17.5 pilots - put that back in. If you have 20's even better, put those in.

I'd expect your issue to nearly clear up below 1/2 throttle but start acting lean past 1/2.

20 65 and 147.5 One size too big down low, and 1 size too small up high, pilots affect the whole range, so you're fine up high but stumblingly rich down low.

Idle is controlled by air screw as well, so you can get it to idle with almost any of 17.5/20/22.5 or even 25 pilots. But as you open throttle its the pilots. 22.5 isn't too bad, but that 65 mids pretty much ruins your 1/8th throttle to 1/2 throttle.

BTW on a 89-00 bike, with a 42.5 pilot you will need to take off @4k, else you'll stall it. Too rich to make decent power for a good take off. I suffered with it for a year almost when I first got the bike.
Cool.
Buddha.

[gsatterw]

Thanks Buddah, I will try this tomorrow. I have some 17.5's. I also have 62.5's and 60's.

Think I could get away with 22.5, 62.5 and 145?

[Slack]

I just took my wife's bike for a spin last weekend.
It had been sitting way too long, and the gas was old. It was surging badly at anything less then 1/4 throttle. I hit the reserve after 30 miles or so, pulled over and put some fresh gas in it, and it ran like a top.
Might want to drain the tank and get some fresh gas in there.


Do you have 145's or 147.5's? Your posts say one and your sig. says another 

[The Buddha]

17.5 and 62.5 may get your low end a bit lean, but the top end could clear up.
20/62.5/147.5 may be the best option. No 20 or 147.5 huh - well send me $$ and I'll get it out your way.

Cool.
Buddha.

[gsatterw]

I just took my wife's bike for a spin last weekend.
It had been sitting way too long, and the gas was old. It was surging badly at anything less then 1/4 throttle. I hit the reserve after 30 miles or so, pulled over and put some fresh gas in it, and it ran like a top.
Might want to drain the tank and get some fresh gas in there.


Do you have 145's or 147.5's? Your posts say one and your sig. says another 

Huh. Good catch. I'm pretty sure I saw 145's in there yesterday, but I could have misread. I'll have to check on that.

Good thoughts on the gas. I'll check it out. I'm thinking of just swapping all of my jets. I couldn't get all of the corrosion off and could have some piece of mind for a few extra bucks.

I wasn't able to do any work today, I was made to go 'shopping'.

Will check back tomorrow. Thanks all.

Graham 

[The Buddha]

Didn't you buy something from me a few months ago ?
But, I don't stock 145's or 22.5' though.

Cool.
Buddha.

[gsatterw]

Didn't you buy something from me a few months ago ?
But, I don't stock 145's or 22.5' though.

Cool.
Buddha.

Don't believe I've ever bought anything from you thus far.

[gsatterw]

Alright,

So I swapped all my jets to 20, 62.5, 147.5 and changed out my gas.

Runs like a champ now.

Yay thanks all.

Graham 

/thread