JD transmission main gear wear

[Doc-54]

How much wear is acceptable for the main gear cogs?
These cogs measure 1.5mm lower on the leading edge.

[dukekleman]

Doc,
I'm not exactly sure on your JD , but on many other trans gear dogs, a lead in ramp angle as shown is normal and not actual wear. Perhaps someone else can confirm this on a JD.

Duke

[Steve Slocombe]

There is no chamfer on my original main gears, and no reason to have one as the gear is in in constant mesh with the countershaft gear. It is the sliding gear and the middle row of the cluster gear that get the chamfered edges in this crash gearbox. I would be more concerned with the angled ramps in the top of the pictures, as excessive wear here can mean the bike jumping out of top gear.

[dukekleman]

Doc,
For clarity regarding your question...
In the photo of yours I marked (A) and (B) with red arrows.
Is this the area of the gear you are concerned about and has a 1.5 mm variation in height?
image_42268~3.jpg
Thank you,
Duke

[Doc-54]

Yes. I couldn’t find any pictures of what a new one looks like. As you posted, some main gears are ramped like this one. Didn’t know if this is normal or not.

[Steve Slocombe]

Yes, that's normal, and there are matching ramps on the slider gear. Third gear is direct drive, and relies on the slider gear nesting firmly in the back of the main drive gear.

[Doc-54]

Thanks for the help!