Need to know about carb adjustment for tomos st sept 2010 question 1 the screw adjust questtion 2 finger turn adjustment what do either do and if totally screwed in how many turns out do i do to either so that i can begin to proporly tune?

For the initial settings - 03-12
- lightly seat the pilot all the way to the back - lightly, too much torque and you'll ruin the o-ring in there - then back out the pilot screw 1 & 1/2 turns. From there - you let it run for 10 minutes or so and then adjust the idle to 1,300 +/- 50 rpm - turn your handlebars left and right after adjustment of the throttle lever to make sure it's okay and not binding up - and do your adjustment from the throttle stop screw. According to the specs, once you set that pilot at 1,300 +/- the rest of the adjustment is done with the throttle stop screw. If you do all that and it's still not picking up fuel - definitely give the intake/carb boot a good look over for any cracks or anywhere vacuum could escape - and if it still doesn't pick up the fuel - give the throttle set screw a turn or two. Had a 2000 Yamaha XT225 carb I rebuilt a few weeks ago - adjusted everything as instructed - but it wasn't picking up the fuel. I gave the throttle set screw about a 1/3 turn in to put a little nudge on the throttle and it fired right up. All The Best and Good Luck - Justin Lee, 17 South Industries, LLC

You need to adjust the idle 1st.Main jet #58 is just for wide open throttle. Start by turning air screw all the way in "gently" till it stops, and back it out 1 and a half turns. Back out idle screw until slide is closed " not touching slide" . Turn until just contacts slide plus 1 full turn in opening slide. Start it up with the choke on and turn the air screw slowly in or out and slowly move the choke off till you can get it to run with the choke off. Than adjust idle screw " the one that moves the slide up and down to set the RPM. If you cant get her to idle with the choke off and the carb is air tight on the intake manifold. Carb might be to big. If you can get her to idle but it runs ruff I will try to help you tune the carb further. Good luck.

Be careful while doing this
1. Pull out the air pipe between the carb and the head. You will see that a rubber pipe is fitted to carb insulator. Pull it out.There will be a brass pipe. Close it with your finger. If you do not close it your bike will not idle.
2. Now set the mixture screw to 1.5 turns out.
3. Now start the bike. Be sure to close the air injection at carb insulator with thumb of your left hand.
4. Now increase the idle by idle screw to 2000 rpm.
5. Now slowly turn out the screw. I repeat very slowly.
6. You will see the idling rising. continue until maximum idling is obtained. Beyond a point idle will not increase at all and instead decrease. At the point where idle is highest stop turning the screw.
7. You will see your idling is highest and also the rpm needle is constant.
8. Now decrease the idle to 1.2k. stop the engine.
9. Now remove your finger from carb insulator and connect the air injection pipe.
10. restart engine and check idle.

Hi montex124, I will try to help. In the past few years carb makers have been making changes. Some carbs have no adjustment at all, the ports are all fixed inside the carb. Other carbs have only the idle speed mixture screw that can be adjusted, like yours seems to have. Is this screw you mention at the top and completely outside of the carb to adjust the throttle? If it is it's probably the idle speed screw which can be adjusted to any idle speed you want and has nothing to do with the air fuel mixture but If it is right next to the idle mixture screw, it might be the high speed mixture screw but is capped so it can't be adjusted. The low and high speed mixture screws should be marked next to each screw H and L.
The 1 1/2 turns suggested is sometimes just right but other times has to be adjusted, so you can try adjusting it to get your idle but maybe adjust the idle speed screw first to get a higher RPM so it doesn't stall on you. Like I said earlier it just adjusts the throttle, and is like when you are using it, and giving it gas as they say. I hope this helps just a bit. Regards and good luck. Get back to me if you need more help or just let me know how you did. Denis.

2 turns out should get ya started adjust from there. If adjusting doesn't help you may need a new diaphragm. While you have diaphragm out blow through the 2 holes you'll see under diaphragm with air to hopefully avoid pulling carb off to clear screens on pick up tubes. Also check carb mounting screws through carb into tank. They frequently come loose on chippers and log splitters because of hard mount.

do you have adjuster screw's on the carb???

if you do then screw them all the way in then back them out about 1 and half turn then slowly adjust until correct setting's are reached

most likely your idle is to high,,,,, and it is engaging the clutch,,,,lower your idle,,,,,slowly,,,,step by step,,,,till the rear wheel stops spinning,,, remember,,,,, with no one on the bike,,there is very little resistance,,,,, so the wheel will spin easily,,,,,adjust your low side r.p.m.,, and that should solve your problem,,,,,if it dosen't,,, your clutch is probably siezed up,,,, and will have to be replaced. where your throttle cable goes into the top of the carb. ,,, this is where you set your idle,,,,, the set screw is only for adjusting your richness,,,,,or lean fuel mixture,,,,, not your idle,,,

Most carbs have the adjustment removed (EPA) but if yours still has the adjusting screws here are the seat of the pants methods:

One Screw Carb: Turn it all the way in and then back out 3-1/2 turns, start the engine and make slight turns in or out until the motor runs smooth from idle to wide open, do not get it too lean, turn in until max RPM is reached then turn out 1/8 turn and go from there.

Two Screw Carb: You adjust the one to remedy either the low or high, high is adjusted until the motor runs smoothly under load at high RPM and the low is adjusted until idle and off idle is smooth.

There is no lamel valve, unless this is a foreign language. Your carb is not clean. It may appear clean, but the pilot system is still plugged. Replace the pilot jet, or get it totally unpluged. could be another part of it also.