starting tearing down 6 hours ago have the bottom case ready to split but I can't get the magneto rotor off of the crank does any body have any suggestions on how to farm boy enginer it off. Or do I have to get a puller. also if no ideas wheres a good place to get a puller with out getting a hole in my pocket at the yamaha shop

 

ya you need a puller for that i take apart atv motors every day id go to any car part store and you can get one fairly cheep it will come off really hard so you might have to lightly tap on it with a hammer to get it to pop

 

First time every tearing one down, first time for any gas motor to be honist I get to play with diesel's all day seams ok I didn't know they sold atv tools at auto stores. any recomedations on what to replace while I'm in there installing a 471 stroker so far I ordered new timing chain, guides both sides and upper, timing chain tesnsioner gasket and oil pump gear, the only thing I'm not sure on yet is it had a lower end knock when I flipped it up with magneto up a bearing fell out of some where in the on the clutch side it almost looks like its the size of the crank bearings but not sure. it still ran good when I took it apart. if the crank bearings were that bad I figured it would have locked up.
thanks

 

there pretty simple to tear down id just check the bearing making sure there no slop in them and im pretty sure it was the crank bearing fell out one other thing might be just replace the ring on the piston so its good and snug again but there pretty simple motors

 

ya i got a 12.5/1 piston new rings, new crank/bearings and all gaskets to put back together can you press new sleeve's in these I have some minor scoring figured while its on the bench I might as well do all it needs. how bad is the tranny once the case is split

 

you can press the sleeves out if you have a press or you can hone it to get ride rid the scaring and polish it up the tranny not to bad you just have to make sur you put all the gears back were the go and when you take it apart just remember how it came apart so you can put it back to gether the way it came if you have anyother questions when you get into it just let me know

 

thanks for the help.

 

no problem i enjoy sharing my nowledge to people so they can learn how to do it just message me if you run into anything else once you get further into it ill be back on tomarrow night after i get done at work