I got 65 thru 70 think I will start with 69 and work my way down. Lol.
Jet change
- Thread starter Kman123
- Start date
Tyler6357
Well-Known Member
That's a good idea, start high and work your way down, just make sure that you get the engine good and hot before you make an analysis, one of my bikes always 4 strokes until it's warmed up and I have a #60 in. Don't forget, it's always better to be a little on the rich side than be too lean. Rich will just make it 4 stroke sometimes and if it happens with a big load it at the wrong time could blow the head gasket, however, running it too lean can cause over heating followed by very bad things happening to the cheap Chinese parts causing major parts damage. Yep, rather be too rich than too lean.
gary55
Well-Known Member
GreasyChris is right. You are doing it right. Though it will probably like something lower than a 69 it's wise to err to the side of not frying the engine with too large a step at first. The reason it 4 strokes a little less when warm is unlike and opposite of Tyler suggests a warm engine runs leaner than a cold engine, Thus the need to choke a cold engine and why it will usually idle down a little after warmed up.
gary55
Well-Known Member
So I'm guessing it's the Dellorto clone carb your using? They tend to run richer than the NT's and need a smaller jet than the NT to clean up.
So how do I know what is the best jets to use? The motor seems to run fine with several jets. Not four stroking with the .68 .67 and the .66. Still never really got back the high rpms. But runs good. Even down hill the motor will try and go even faster although I let off the throttle so Its not screaming. But still which jet is best or should I go even leaner?
