Rear gear box

[ceedubs]

I recently installed a used rear gear box . The old one final drive spline was worn-out. On my first ride with the replacement gear box of 30 miles. I put my hand on the rear gear box and it was hot enough that my hand recoiled from the heat. It was not hot enough to burn me. Is that normal heat. I double checked the gear oil. Lucas 85/140. Gears felt good when I had it on my work bench. Thanks.

[Andy Cote]

Don't think that's right. Brakes dragging? Otherwise a bad bearing.

[plain]

The internet says 120F or higher will hurt your hand so maybe if it was on the sole of your fingers or palm you might stand a little more. 120F doesn't seem like too hot but only 30 miles really doesn't tell the tale, I would think. When you've picked up a hot tool that was laying in the sun it was only the temp of the day so that should tell you something. I usually put them down pretty fast when they are like that.

[ceedubs]

I got a temperature gun at work. I will borrow it and get an actual temperature. It surprised me when I first touched it. Thanks for the information.

[plain]

Just an update. I rode about 40 miles yesterday and felt the final drive when I got home. It was pretty warm but I could hold my hand on it no problem. I think probably not over 105F but I didn't shoot it with a temp gun.
Also, can I ask how many miles you had on your wing before the gear went out and do you think it was due to a leaking u-joint boot? I changed the boot but didn't take the driveshaft out recently because there was no evidence of moisture entering the swingarm. I have about 50K.

[ceedubs]

I bought the bike used. 49kmiles. The O-ring was worn and no grease on spline, final drive flange spline was worn about 80-90%.
I got the final drive flange spline and the matching gear box off ebay.
I was able to hold hand on gearbox, but it was uncomfortable hot. Not hot enough to burn me. Thanks for the information.

[plain]

You may have already moved on from this but today I rode about 50 mi. at highway speeds 60-70. I put a new Dunlop E4 on back and just changed oil in the differential about 450 miles past. I took a temp gun and shot 136F in the middle of the back tire (E4) and 141F on the gearbox so looks like it should be warmer but maybe not much different that center of tire tread. I haven't taken any long trips yet.

[ceedubs]

Thank you for posting this. I got a chance to ride. I rode around 40 miles on state routes and interstate. I brought a temp gun and got 140* constantly. I had no idea what it should. After install a used rear gear box I thought it might be high. Thanks again. Nice to have a community of gold wing riders to get information from..

[FM-USA]

... I rode around 40 miles on state routes and interstate. I brought a temp gun and got 140* constantly.
... After install a used rear gear box I thought it might be high.

Still puzzling those high temps you first reported, likely low oil.
There's not many parts in the rear gear, or most other areas, that would be hurt by rather warm temps.
Cheapest wheel seals and O-Rings would be made of nitrile rubber & their temp range about -25° F to 215° F* .
Looks like you're ALL GOOD with 140F* .

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