I just rebuilt my nephews blaster.The old wiseco was worn out and i put the new one in.Had it bored .20 over.I have done the break in on the motor. I check the ring gap before i install the jug they were good. Now when you put it in 6 gear it makes a weird noise in it.The crank was still good bearings were good.Before i rebuilt it it had piston slap really bad horrible noise.The sound is like a low beating thuming sound,. I took it back apart and everything look good in it. I dont know what it is has anyone else have this problem out of thier blaster.Thank in Advance Brian
Help with noise in the motor!!
- Thread starter ajaysblaster
- Start date
Check the final drive. Good sprockets/chain? Sprockets secured? Odd that it's only 6th as that gets least use/abuse. Before I pulled motor I would pull clutch and spin trans by hand to locate problem. Is noise constant, on/off throttle, cruiseing?
Could be time to break out a measuring device to see if parts are within tolerance!
I'm wondering the same thing. Was the bore checked for straitness (taper),and roundness? Was the piston to cylinder clearance set properly...about .0025 for the wiseco?
Or... did you just slap a new piston in a cylinder that was bored "a while back" to .020,and did this with out checking anything?
If so,that doesn't count.
No i just had it bored with new piston.I check the cylinder from top to bottom with the rings in the motor .It was all the same .The people i have bore my stuff does a great job on them.They get my lt250r in jug perfect everytime i send it to them.I rode it this afternoon.It pulls the best its ever had has seen i got it for my nephew.The noise comes in as the motor is coming onto the pipe.It was doing it in every gear tonight.But it ran great.Maybee i just worried about it.Maybee its a common noise for these motor.They are very noisey motor anyways compared to other 2 strokes.Im pulling the clutch case off tomorrow and look around in thier.If that doesnt work il split the case and replace all the bearings in the motor.
While you have the clutch cover off check the counter balancer gear and bearing closely, don't know which of mine failed first, but I ended up with more "pieces" than stock X(. Also check kicker idler.
X(. Also check kicker idler.
Silly question I know, but what gearbox oil, type and how much.
I had a bike sent to me with a similar problem, wrong oil, had a friction modifer in it clutch was slipping and vibrating when the power came on.
I had a bike sent to me with a similar problem, wrong oil, had a friction modifer in it clutch was slipping and vibrating when the power came on.
I think i put 10w 40w Suzuki atv oil in for wet clutches.The clutch isnt slipping on it.Basket has chatter in it when it idles .
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.
I took clutch case off.I took the clutch basket ,check the idle gear it was tight.Took the blance shaft gear off .It was smooth and tight. Main bearings seem to be tight no play.The only thing i could find was the transmission shaft wear the clutch basket goes on had some play when i pulled out on it.But their was no up and down play in it.I going to put it back together tomorrow and run it and see.
They looked good. It seemed to have a little wiggle when you pulled on it hard. I think it should be alright.
Boyshen replacement reeds. Uni air filter,Air box lid on .Also .20 over.Stock carb and Fmf pipe with power core. It has stock pilot and a 240 main which im switching to a 250 in a minute.It had 360 main in it when we got it.no air box lid fmf and reeds and no air filter.That probally why it was wore out when we got it.Also they broke the needle so the needle was staying down when it was wide open.No wonder the rings were fired when i took it apart.
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
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