RT 180 giving bad vibrations in low rpms

[yamart180]

I went out for the first ride of the year and everything seemed fine. I let my friend ride it at a rock pit and he noticed it was vibrating alot in low rpms but once you got going it was fine. As we rode home it got worse and worse. The only new thing I did to the bike before this was I put a 13 tooth front sprocket instead of a 14 but this doesnt explain it vibrating in neutral while idling. I also tried riding in the snow but I only got 10 feet from the shed spinning all the way and called it quits. Please tell me what you think it is.

 

[Red Ryder]

Are all your engine mount bolts secure?

 

[yamart180]

Good idea but I just checked and they are all tight.

 

[Red Ryder]

That's kind of strange, I can't think of much else. And you say it never did it before?

 

[2 strokes for life]

You might have a crapy connecting rod bearing.

 

[yamart180]

nope this is the first time its done this

 

[yamart180]

put all new bearings in last sept. and rode quite a bit since with no problems until now. It's well past break-in now. I cant figure out why some thing would go so bad in one ride.

 

[2 strokes for life]

I dont have the slightesed clue what it could be.

 

[yamart180]

pulled off the jug some dirt got in but all bearings seem fine. checked play on everything all up to specs. please try to help i realy want to ride spring break. :(

 

[Red Ryder]

This is totaly beyond me man.

 

[chicoman]

grab your cylinder head with both hands and try to move it, a bad mount can allow the engine to move even if the bolts are tight. Also, check to make sure that your exhaust and swingarm pivot bolt are tight.

 

[yamart180]

i dont know how or why but just cleaning the engine inside did the trick. It's fixed now, thanks to all who replied.