tuning carb on low and mid range

[superspec]

hey guys ive looked all around trying to find the proper way to tune the carb on my 03 blaster. its pretty standard mod list: toomey b1 pipe, vforce reeds, uni filter/outer filter. still has TORS, stock oil injection.

the problem is in the low and mid range trying to hold a steady speed (10-20mph) area itll run smooth for a few sec then its like somebody pulled the spark for a sec and its right back. it repeats this cycle constantly. on topend it pulls perfect. this bike has been jetted before and i personally rebuilt the top end several years ago and it ran great at the time. im pretty sure that my brother pulled the carb a good while back to TRY and clean it and its no telling what settings he messed up. the needle is set on the middle slot right now, idle screw is at 2 turns. i didnt know what to do with TORS so i didnt mess with it. also it will not idle.

if someone could point me to the thread on tuning the stock carb it would be much appreciated!

thnaks
charles

 

[sicivicdude]

Pull the carburetor apart, remove the pilot jet (it's the one down inside the tube beside the main jet) using a small electrician's style flat blade screwdriver, clean out the pilot jet using carburetor cleaner and a small tube (the little red tube taped to the side of the can), clean out the carburetor passages leading from the air needle (inside the air horn) to the pilot jet and from the pilot jet into the carburetor body (behind the slide).

Reinstall the pilot needle and the carburetor, turn the air needle in 1/2 turn to start with. Once you've got it to idle, follow the jetting guide to adjust the air screw until it idles the highest possible.

 

[superspec]

the carb is clean. i pulled it apart before i even tried to ride it other than from the garage to the trailer. when i got it the idle screw was bottomed out.

 

[Awk08]

is it possible someone changed the pilot jet to a different one, very few etremely modded bikes will the pilot need changed on a stock carb, the 32.5 that is stock will work for most, pull it again and check the size
and the airscrew turned in the whole way is indicating a lean or clogged pilot

also check the float level, as that will effect every jetting range, it should be
20 - 21.5mm from where the gasket would sit
measured like this...............

 

[superspec]

there is zero chance that someone changed the jets. my brother was 12-13yrs old when he got it and is 18 now. the boy would struggle to change a light bulb. its all in the settings at this point. the idle screw wasnt bottomed out because it needed it but more because he was dicking with things he had no business messing with which leads me to belive he just turned a bunch of screws and got it out of whack. where should the TORS screw be in relation to bottomed out?

 

[Larry's Shee]

Start with the air screw 1 1/2 turns out. Only screw on TORS is the throttle slide idle (height), large thumb screw on top of "brick"