Teeth grinding out

[Stoneman]

can anyone explain why this might be happening on a motor
All bearings feel fine

 

[FurryOnTheInside]

Waiiiiit. NOW I see it! Teeth all gone. Idk why if it was greased. I hope you bought a spare so you're not waiting weeks to replace it.

 

[machanic]

There is the possibility the gear was not heat treated to the proper hardness, and in the pic the tooth engagement does not look deep, you said the bearings felt good but did you check the bearings in the clutch, they can only be checked with the clutch disengaged or outer plate removed on the clutch.

 

[crassius]

it wasn't greased at factory - probably died in less than a week

not sure which factory is doing this, but best to grease that gear yourself before starting a new motor

note my thread; "saw something new today" in 2-stroke area

 

[Stoneman]

There is the possibility the gear was not heat treated to the proper hardness, and in the pic the tooth engagement does not look deep, you said the bearings felt good but did you check the bearings in the clutch, they can only be checked with the clutch disengaged or outer plate removed on the clutch.

I had checked both bearings and both seemed fine

This is the second on this motor chewed out. First one with no grease and second one with grease

 

[CrazyDan]

The bottom-most tooth on the big gear looks a little damaged in that pic. If that's the case, it would wreck a 3rd small gear in no time flat.

 

[Stoneman]

The bottom-most tooth on the big gear looks a little damaged in that pic. If that's the case, it would wreck a 3rd small gear in no time flat.

At the bottom left?

I will check it out.

 

[Stoneman]

it wasn't greased at factory - probably died in less than a week

not sure which factory is doing this, but best to grease that gear yourself before starting a new motor

note my thread; "saw something new today" in 2-stroke area

Your right, wasn't greased and only lasted a couple of days.

But i did grease the second one installed.

 

[crassius]

I always check all teeth on big gear with machinist's pick in case debris is stuck up in other teeth - also, one must check new small gear for wobble before running it.

 

[Stoneman]

nothing noticeable on the teeth, all looks good

Im at a loss