Originally Posted by
kevinjh
No Mate 148 deg f, Idle gap set at 0.7 as you told me and tuned as per mm tips. HSN 3/4 in from flush, lsn 1.5 in from flush.
Thought it was running fine although clutch was a bit worn at end of the final.
have found some plugs on the bay now in UK, helps that i did the search again with the correct spelling lol.
Will get new plugs and try richening the top as Dave said and see how it goes although this time i will do it on a non race day as i can get the engine fully hot, i think the engine set on the bench runs fine but as it is not hot is leaning out over a race causing the problem.
Have definately got the message about the idle setting now lol. I know I have over leaned the top and had the bottom too fat as that advice on machine gunning you gave me was very noticable when i was looking for it and easy to spot,
On the bench i leaned the top end to clear fully throughout the range but have been told to leave slightly rich. I think my mistake has been trying to tune on a race day where you can not heat fully and time is against you.
Hey that's cool Kevin. 148 C would have been just a bit warm
3/4 in on the HSN does sound a little far in. We normally find 1/8 to 1/4 turn in on the HSN is plenty for a full race tune with the long needle set up.
To get a real spot on race tune it's an idea to run the buggy for 3 consecutive tanks at race pace and fine tune over this period. The chassis is a very good heat sink, but at race pace the chassis will heat up to a point where it becomes saturated with heat from the motor, and will not accept anymore heat. This additional heat is then pushed back into the motor. This is the point where your motor can overheat. If you tune for this over the 3 continuous tanks, then you can run hard in those longer semi's and finals confident that your motor will not get too hot at any stage.
Tuning on the bench may not give good performance on the track for many various reasons.
Conversly, you may have just had a dud plug