Triumphrat

Caulky

It may be more economical to order 57-4779 high gear from the UK.
$92.1 US [£58] from here plus delivery...no VAT.
http://www.tms-motorcycles.co.uk/sto...asp?cat_id=151
I have no idea how much postage and packing would be, but they are pretty quick.
And their stuff is good quality.
You could also order other parts at the same time.

rambo

I left a message on youtube for you.Yes,your bearings are knackered.Ride it more and you will have no gearbox very soon.That shaft should have no play in it.Clutch must be jumping up and down in there

Mr.Pete

This is most likely the problem.There are 2 versions of output sleeve gear,and you can only get the bearing for the later one.

If you replace the bearing,you need to replace the sleeve gear to suit it.You may have had no trouble using the original bearing if it was OK.

Cybersausage

Just for info..I was told that these bearings wear out causing excessive play, if your chains are too tight.

rambo

That is certainly true sausage.I think the original poster has put this together with a wrong or worn part.As the video shows,he didnt realise there must be no play in the gearbox shaft.
Personally,i have never had a leak in this area in 34 years of T120 playing and i dont use any silicone on the shaft.I suppose if i had a close look there might be a weep.The silicone looks like good workshop practice so i might try it next time around