ok it was just weird that the tune changed when i got off the track it was running fine.


i have a enough top end so i guess i have lean the low end needle out more when the weather changes a bit. but could lean the main needle a bit more also .

The tune will change if the weather changes. Lean the hsn some to.

ok i , will give that a try than when i was in the main there was light smoke coming out of the pipe by the way but the idle still was kind of high when i pitted during the main.

i have my dad pit for me so he doesnt know .

If there was only light smoke then don,t lean the hsn.

=cdc;8020957]If there was only light smoke then don,t lean the hsn.[/QUOTE]

The throttle trim might not be set right.

oh wait, i did have it a 20 % to the right on the throttle trim by a mistake but i did set it at 0 and i was having, a problem with the idle not coming down when i hit the gas it whould come back down than it wouldnt but i tried to slow the idle down so it must be the lsn too rich than.

but i am checking my clutch.

Ok make sure there is no broken clutch springs.

yea i will im going to buy some new ones.

im going to replace my clutch bearings i need to replace them anyways.

Replace the clutch bearings , springs and shoes if needed then reset the idle gap and the throttle trim. Then if the engine is still having that problem lean lsn a little.

well i know im going to have to reset the idle gap i will check the clutch shoes but i think there fine there not old really not even a gallon on them.

but im defielty getting the 53 pipe though.

Once you have your idle gap set right you just need to lean or richen the LSN till the idle is right. In general if your LSN is in from flush your too lean. You should run rich and somewhat slow for the first 3-4 laps and slowly get faster and faster as it warms up. These are cold blooded engines for the most part.

ok i got you i need to do the tuning more on the track than do bench tuning with the lsn . there is plently of smoke coming out of the pipe when i warm the engine up .

cold blooded engines ?

so with the idle about 1mm like the thicknest of a credit card ?

Yep about the thickness of a credit card but you MUST remove the carb restrictor to do this. If you set it with the restrictor in it your gap will be too big and your going to end up rich on the LSN to compensate.

I actually prefer to bench tune so you know you have it close before you get on the track. After you have the Idle gap set fire up the engine, if the idle is high richen the LSN, if it won't stay running you need to lean the LSN. This will get your LSN set good enough to start tuning the engine in. Now blip the throttle for a minute to get some heat in the engine. Once warmed up give it full throttle, you want the engine to rise in RPM's nice and fast but only max out at about 80% of the max RPM's. If it really screams and does not stop climbing you should richen it up. Once you can hold full throttle and it gets to max RPM and stays at max and does not continue rising your HSN is close. (When I say hold it full throttle thats only like 2 seconds max.)

Now when the engine goes back to idle after that full throttle hold what the idle does will tell you what the LSN needs. If it immediately drops to a nice steady idle and stays at the same idle for 20 seconds then you got lucky with the first LSN setting and your good to go. If the idle stays a little high for 2-5 seconds then drops to a low idle you will need to lean the LSN. If it drops to a good idle for a split second then revs high again you need to richen the LSN. Remember that now as you tune the LSN in small amounts you may need to make very small adjustments to the idle gap.

Now throw it on the track and run... when I said cold blooded I meant that they take a while to warm up.. like 2, 3 sometimes more laps.

oh crap when i messed with the idle i dint remove the restricter now i know why you are supposed to . good info thanks !

il be racing next weekend so i will try that and make sure my clutch is ok too .

i am going to get the 53 pipe so i have to retune anyways.

here, this one i did good in yesterday in the sportsman truggy class and i told my dad today that my engine wasnt running right.. and he said well you did good why do you want to mess with it and i said it wasnt running right you dont drive it you wouldnt get it.