It's been a few years since I've posted anything here,  but now I need help looked and searched other posts and tried different things but now I'm lost.  Here's the issue:
I have a 96, while im cruising with the fuel petcock on prime at partial throttle when I get around 7-8k rpms the engine starts to sputter and surge.  If I go full throttle it pulls smoothly out of the sputtering sensation. 
When the petcock is on ON it feels like a fuel starvation problem at any cruising speed,  then full throttle and it pulls right out of it. I've pulled the carbs apart and shot carb cleaner through all the jets.  I have a high flow filter in line,  it's not a paper filter.

Thanks for any help

7-8k rpm ? what throttle position ?
You may need a wosher for z needle. But post details, pipe air filter jets
Cool.
Buddha.

Throttle position is about half throttle,  I have a lunch box k&n,  had the timing advance mod done,  where I send the guy mine and he does the mod and sends it back,  exhaust is stock.  Front sprocket is oem and the rear is one tooth smaller.  I did do the add a washer trick,  and I forget what size it was rejetted to I think just the next size up.

Add another washer under needle. If that doesn't do it, go up 1 on the mains but remove both the washers.
Since you've not posted what jets you're running, or other issues, I am going to assume everything else is perfect.

Lean enough to not lean surge is far different from being on the spot right. But the added washer or the larger main could get you to where it doesn't surge.

Cool.
Buddha.

Cool,  thanks for the suggestion,  I have limited time during the week to work on my bike now that I live in an apartment complex. I'll post this weekend wither it worked or not,  again thanks!

Alright so, this is what i did and more info and now what its doing...

The jet kit thats on it says 125 rd, i do have a lunchbox k&n, stock exhaust, advance timing mod, and a high flow mesh screen filter hooked between the fuel petcock and the line going into the bottom of the carb.  i took all the jets out clean them and in all the passages, with 2 #4 washes in each carb, along with the air fuel mixture 2 turns out. also im a single rider that weights 265 lbs.

and now heres what its doing:

petcock set on prime and set the idle to 1300ish and took it around the block. still has the surging and hiccup sensation at partial throttle cruise in between 7-8 and then wide open throttle it and it smooths out, it happens only in 2 and 3 gear.

petcock set on ON and same thing but only in 2 gear.

while both on ON and PRIME after it warms up and the idle doesnt go back down to 1300ish it stays around 4-5k. the only way to bring down the rpms is to while in gear hold the brake in and slowly let the clutch handle slowly out as if to stall the engine, then when it get lower i stop and it stays around 1300ish.

thanks for any advise guys!

also this isnt a new bike to me ive owned it for many years. this problem just started to happen last year. 

Hi just having a look at the forum and notice your problem .Would suggest you look at an air leak in the inlet rubber mount that the carb slips into between,the carb and cylinder head .These are known to deteriorate especially if you have pod style filters as they take all the carb weight .Look for cracks in the rubber and slackness where the hose clip holds the carb on .Also check where it is bolted to the head.

Quote from: Cusimano on August 26, 2015, 08:11:49 PM
Alright so, this is what i did and more info and now what its doing...

The jet kit thats on it says 125 rd, i do have a lunchbox k&n, stock exhaust, advance timing mod, and a high flow mesh screen filter hooked between the fuel petcock and the line going into the bottom of the carb.  i took all the jets out clean them and in all the passages, with 2 #4 washes in each carb, along with the air fuel mixture 2 turns out. also im a single rider that weights 265 lbs.

and now heres what its doing:

petcock set on prime and set the idle to 1300ish and took it around the block. still has the surging and hiccup sensation at partial throttle cruise in between 7-8 and then wide open throttle it and it smooths out, it happens only in 2 and 3 gear.

petcock set on ON and same thing but only in 2 gear.

while both on ON and PRIME after it warms up and the idle doesnt go back down to 1300ish it stays around 4-5k. the only way to bring down the rpms is to while in gear hold the brake in and slowly let the clutch handle slowly out as if to stall the engine, then when it get lower i stop and it stays around 1300ish.

thanks for any advise guys!

also this isnt a new bike to me ive owned it for many years. this problem just started to happen last year.

Lunch box and stock pipe  - no clue - but its somewhere near 142.5 ... not 125.

Cool.
Buddha.