Help with noise in the motor!!

[Blaaster]

so this isn't predetonation?

I think you nailed it Scot, I was leaning towards detonation from the first post, when it was said only in 6th gear.

I thought, naw to obvious, it would happen in most gears if it was detonation.

Then in post 8 it was stated that it was doing it in every gear, how did I miss this \/ \/ \/

The wierd thing is the motor sound great at idle.Motor sound great in the upper rpms.It just when it comes onto the pipe is where the noise is.

 

[ajaysblaster]

you will be too lean even with that 250. you need about a 280 or 290 depending on where you live and how cold it is right now. hell maybe even a 300. summer jetting should be around 270-280

2000 feet at my house and i ride up to 4000 feet.I put the 250 in and move the needle down to 3 clip.It fouled the plug in about 5 minutes of ridding.Put a new plug in well a used one didnt have a new one at the time.I moved the clip back to the leanest setting and it has ran find after that.Still a noise in it and the clutch seems to be slipping but i think i got it to tight after i adjusted it before i put the clutch cover back on.I dont know if the needle is stock or not.I couldnt find my other rebuild kit because it has the stock needle in it.Whats weight oil does the gear box take.I put 10w 40 w in it.

 

[Larry's Shee]

Was the oil specifically for "WET CLUTCH"? Or just any old 10-40?

 

[ajaysblaster]

Was the oil specifically for "WET CLUTCH"? Or just any old 10-40?

Yea its suzuki atv oil for wet clutches.It suzuki brand like yamaha lube is yamaha brand. I have lt250r that i use it in.Im justing wondering what the blaster uses 10w 30w 10w 40w or 20 50w.This the first blaster i have ever messes with.Im going to do a complete bottom end rebuild in it in a month or so.All new bearings blance shaft gear sprocket all new seal.I dont know how old the stuff in the motor.The case has been split before.I feel better with it all fresh.My nephew is going to race some next year.So its time for it.

 

[ajaysblaster]

I think you nailed it Scot, I was leaning towards detonation from the first post, when it was said only in 6th gear.

I thought, naw to obvious, it would happen in most gears if it was detonation.

Then in post 8 it was stated that it was doing it in every gear, how did I miss this \/ \/ \/

Well when i first heard it was only in 6 gear.I was still taking it easy on it in break in.That why i didnt hear in the others.I ran 6 a little harder then the rest.But on jetting i put the 250 in drop the needle to middle spot and fouled the plug in 5 minutes.Left the 250 jet and moved the needle back to the top to lean it out and ran fine for 2 hours this evening.Pull super strong.I have rode 2 blaster before and it would smoke them like they would be sitting still.

 

[Blaaster]

Well when i first heard it was only in 6 gear.I was still taking it easy on it in break in.That why i didnt hear in the others.I ran 6 a little harder then the rest.But on jetting i put the 250 in drop the needle to middle spot and fouled the plug in 5 minutes.Left the 250 jet and moved the needle back to the top to lean it out and ran fine for 2 hours this evening.Pull super strong.I have rode 2 blaster before and it would smoke them like they would be sitting still.

Something really queer going on here.

A FMF calls for a #260 main jet with the needle on the middle clip, #270 or bigger taking into consideration cooler temps and premix.

The float must be borderline allowing the maxiumum or possibly too much fuel into the bowl at low demand, and the jetting and needle leaning it out on high demand.

In all my years in 2 stroking have I known a needle have to be run at its leanest setting if the float level and the idle is set correctly!

What plug are you using, I use the recommended b8es, stockish motor, DMC Alien pipe, #320 main jet needle on lowest clip with 25:1 bean oil in temps of over 100 degs and have never looked like fouling a plug.

I can't remember the results of your leak test, how long did it hold 7 psi?

 

[scotj77]

Well when i first heard it was only in 6 gear.I was still taking it easy on it in break in.That why i didnt hear in the others.I ran 6 a little harder then the rest.But on jetting i put the 250 in drop the needle to middle spot and fouled the plug in 5 minutes.Left the 250 jet and moved the needle back to the top to lean it out and ran fine for 2 hours this evening.Pull super strong.I have rode 2 blaster before and it would smoke them like they would be sitting still.

well like i said you are too lean. if you are fouling the plug with the 250 main there is somethin else going on. have you checked your float height?

the reason you only detonated in 6th is bc that is the only gear you put load on it in. now you have tried riding it harder in the other gears and it is detonating agian. I really hope you let off when it starts detonating and havne't tried to "push" through it. the stock carb really runs best with the needle in the middle position from what i have found. there is something else going on here besides lean jetting if you foul plugs and detonate........

What kind of plug fouling are we talking?