850 final drive gear oil capacity

[jayel]

got a final drive off a 81 850LH put it on and it overfilled at around 7 oz. checked and spec is 10 oz. (300cc) any ideas? lesser capacity because plugged oilholes in the pinion cup?

[BA80]

Is it overfilled according to your guage?

[jayel]

well if you try to put in 10 oz it's all over the floor I lowered it to bottom of fill hole threads will check it with the guage tomorrow but definatly less capacity if it's not able to fill the drive shaft cup just wondered if anyone else noticed this and if anyone has a idea of new capacity.... took it around the block and much better, easier shifting thru first three gears, don't feel like it needs SHIFTED NOW, 60mph @ 3500 in fifth think it's what I wanted

[BA80]

I think you need to drain it and start over. The capacity is the same as the 1100.

It's more expensive but I personally recommend using full synthetic 75/140 in both the middle and final drives.

just sayin'

[CaptonZap]

If you use the factory recommendation for the 850, after doing the conversion, you will indeed overflow. The reason is that the 850 filled the drive shaft spline cavity with oil, while the conversion blocks that chamber off, and uses grease instead.
Get or make a dip gauge, and go from there.
Without benefit of gauge, start filling, a little at a time, until you can see the surface of the oil when looking straight down into the fill hole. That's close, good enough for a round the block blast. CZ

[jayel]

the capacity has to be less, you plug the two oil feed holes in the pinion cup where the end of the drive shaft runs and fill it with moly grease (300cc) that used to be oil filled, it can settle overnight and I'll get a truer reading

[BA80]

The 11 calls for 10 oz. like he said CZ.

[motoman]

I think you need to drain it and start over. The capacity is the same as the 1100.

It's more expensive but I personally recommend using full synthetic 75/140 in both the middle and final drives.

just sayin'

+1 on the syn. 75/140. If your using syn. lube for the middle and final drive, that be the viscosity I advise running if U want those cases to stay in one piece. The 80/90w syn. has no "cling" in this application. Dino 80/90EP is what was used back in the day, but the syn. cuts down on the whine, less heat from friction, etc.

[BA80]

the capacity has to be less, you plug the two oil feed holes in the pinion cup where the end of the drive shaft runs and fill it with moly grease (300cc) that used to be oil filled, it can settle overnight and I'll get a truer reading

The 11 calls for 10 oz. and it doesn't have the feed holes. I think you may have had an airlock or all the old oil didn't get drained out.

[jayel]

The 11 calls for 10 oz. and it doesn't have the feed holes. I think you may have had an airlock or all the old oil didn't get drained out.

AND RIGHT YOU ARE BA80, after sitting over night the oil level was low so filled to spec using the guage and took it for a 50 mile run, (drive had been sitting in a weed patch for years) drained the oil and got out 10 oz., oil level is below pinion spur gear so the blocked off cup holes really have no effect on the capacity of the drive, just a case of filling to quickly or it needs time to fill in the spaces, refilled taking more time and put in 10 oz fresh refill and it's a happy camper rpm drop of about 500 does 3800/3900 @65 mph took it to the local long time yammie dealer and let him ride it he was suitable impressed, first three gears are usable now too checked temp of the drive with my infared thermo and it was running about 135F after 50 miles

[CaptonZap]

checked temp of the drive with my infared thermo and it was running about 135F after 50 miles

You're right there. I checked temps on a bunch of bikes at the Rally in Durango last summer, and they were all within 10 deg +/- of your temps.
CZ

[jwhughes3]

Thanks CZ

I didn't know you were checking out our rear ends at the Rally to see if we were too hot.



John

[CaptonZap]

I didn't know you were checking out our rear ends at the Rally to see if we were too hot.



John

Aren't you glad I was using a non contact type of thermometer?

CZ

[trbig]

Ehhh.. I just fill the final drive to the bottom of the plug threads and screw in the plug. If it's too much, it'll puke it out the vent hole. Most of the time it doesn't, but if it does, a quick blast with the power washer knocks it all off. I can check the fluid level by eye this way.

[motoman]

Ehhh.. I just fill the final drive to the bottom of the plug threads and screw in the plug. If it's too much, it'll puke it out the vent hole. Most of the time it doesn't, but if it does, a quick blast with the power washer knocks it all off. I can check the fluid level by eye this way.

........fairly easy by eye........when its comin' out the vent....