Transmission Oil Filling Questions

[roger 04 rt]

Please bear with me as I ask a most basic question. Checking/filling transmission oil.

 

Just now I put the motorcycle on the center stand. The rear wheel is on the ground. The front wheel is in the air. I checked the FD Oil, level as expected. Then I pulled the Transmission Oil fill plug and gear oil started to run out so I put the plug back in for now.

 

My assumption is that the last person to change the transmission oil overfilled it maybe by having it on the side stand, but before letting the excess run out. I thought I'd ask the question, "Am I doing something wrong?"

 

If overfilled does anything bad happen?

 

RB

[BFish]

didn't think you could really overfill the 2004RT tranny. on mine it would start spilling during the fill. are you sure the plug removed wasn't the drain plug down below? the filler is above.

[dirtrider]

Afternoon Roger

 

I usually overfill them slightly, probably have for years as I drain overnight with a 3/8" piece of wood under the L/H center stand leg to slightly tip the bike to the right.

 

Then simply put the bike on the side stand & dump 1 quart in. That might give a slight over fill but to tell you truth I never remove the fill plug to check again.

 

As long as oil isn't coming out the vent at high speeds in cold weather no big deal.

 

[roger 04 rt]

didn't think you could really overfill the 2004RT tranny. on mine it would start spilling during the fill. are you sure the plug removed wasn't the drain plug down below? the filler is above.

 

Hey Brian, You did give me a laugh, with the picture in my mind of oil pouring out. That said, I did go check. Top plug.

 

Afternoon Roger

 

I usually overfill them slightly, probably have for years as I drain overnight with a 3/8" piece of wood under the L/H center stand leg to slightly tip the bike to the right.

 

Then simply put the bike on the side stand & dump 1 quart in. That might give a slight over fill but to tell you truth I never remove the fill plug to check again.

 

As long as oil isn't coming out the vent at high speeds in cold weather no big deal.

 

Thanks DR for the tips. I'm going to put the bike on the side stand and close 'er up.

[cris nitro]

If it was me, I would drain some out and recheck it. It would bug me not knowing how overfilled it was.

[Trullion]

On my bike (an RS) either wheel can be off the ground when the bike is on its mainstand, on which the bike is very finely balanced. I prefer to fill the gearbox with the front wheel on the ground. This appears to result in a slightly higher level than would be the case if I filled the box with the rear wheel on the ground. I prefer to err on the side of slight overfill; using fully synthetic Redline heavyweight oil in the box I feel that significant overfilling could cause a seal to start leaking. It took a few goes to get the oil level right when I changed to Redline; more was added than the supposed capacity to get the level right. However, the level has remained unchanged for a long time now and there are no leaks. I can only assume it is something to do with the viscosity and general "gloopiness" of the oil. What I can say is that it has improved the gearchange and general smoothness of the box, an original M94. Seems to be good stuff.

[BFish]

apologize for causing you to chuckle. i've alwasy filled it when on the center stand with measured amount per the owners manual. never considered the side stand issue.

[skinny_tom (aka boney)]

apologize for causing you to chuckle. i've alwasy filled it when on the center stand with measured amount per the owners manual. never considered the side stand issue.

 

This. Use a good oil and the extra CC's that overfilling will gain you won't make a difference.