12 hp balance gears
 

I'm rebuilding a k301 for my fathers 125 and I am debating re-installing the balance gears? The engine is very low hours and the bearings and end play was good. The only reason I'm rebuilding it is because of rust in the cylinder.


Meant balance gears in title.

Some people do re install them, but most do not. They don't make that much difference in how smooth the engine runs, but if they go bad, they have the bad habit of knocking unwanted holes in the sides of the block. For that reason, very few people re install them when rebuilding a motor.

I dont reinstall them, and I take them out of all the engs I own. One day they will go flying threw the side of the block. Then you will have positive ventlation into you block!

I remove the balance gears from my Cubs soon after bringing them home.

Throw those gears as far away from the engine as you can.

I would pull them out and keep them on the bench.



I fixed your title for you too.:beerchug:

i would keep them, they make excellent weights to hold down the pages of your manual when you are doing maintainance and you can't remember certain specs!!!!! :biggrin2::biggrin2: jeff

Thanks for all the info! I'll be leavening them out for sure then.

I'll be putting a new set back in my k301. as long as you put new parts back in it'll be fine. they say there isnt much vibration (bull) I should of not taken the advice of others. it vibrates the the hood, front light area, heat shield. drives me nuts.

Reinstalling balance gears
 

Doug-

I personally agree with what the others have said here and toss all "grenade" gears. The engine does shake a tad more at idle but after you reach mid to wot the vibrations are no different than before. Another alternative to reinstalling the gears is to have you crank balanced. I've read this will bring the shaking/vibrations back to roughly where it was with the gears installed. This will eliminate the possibility of a blown engine due to the gears needle bearings giving out.

Just my .02 worth.