Trans Oil Change.

[JimmyG]

I know this question must have been asked a hundred times but how do I drain "ALL" the Trans oil out of my model 92 when I pull the drain plug only about half drains out, Do I need to lay the bike overone way or the other?

[Dale]

The motor holds 20 ounces, but you can only drain 16 ounces via the drain plug. The remaining 4 ounces will stay unless you remove the clutch cover and tip the bike to the right side.

[JimmyG]

Thanx, That is what I have found, I just wanted to know if there was an easyer way.

[Zyx]

This raises an interesting question for me. A "complete" refresh on the oil would be ideal, and easier is better usually. Has anyone found a way to safely port the engine case so that more oil drains back to the main transmission case from the clutch cover side of the wall? Or is this even advisable? I would think that no matter at what level the oil drains back or flows back and forth, the clutch cover side would have enough oil to service the clutch, unless the cover side deliberately retains oil at a level above what would be the static level of oil if the oil were free to seek level on both sides of the engine case clutch side wall (which I doubt is the case). I haven't looked at a stripped engine case in several decades, and never thought about it. Sounds like there is something like 4 ounces of oil trapped in the side case, which should be attributable to the height of the opening between main case and side cover. I would not think that the clutch and gear on the cover side would retain 4 ounces of oil just by cling.

[Droptarotter]

Does this engine have a dipstick?
On my KTM 520, I use a vaccum pump to get most of the oil out by inserting a tube into the dipstick hole. I am able to get about 90% of the oil out this way..........which just might work on the Hodakas??

Cheers

[Zyx]

I expect a vacuum pump would work. Don't see why not. Tipping the bike away from the clutch side is going to work to some extent as well, at getting out that last few ounces of oil. Taking off the side cover has the added advantage of letting you clean out any debris that may have accumulated there, such as clutch material, so taking off the cover isn't such a bad thing, just takes time.

[Bullfrog]

There are humps and bumps inside the center cases which prevent oil from flowing to the area where the drain plug is located (in addition to the web that causes some oil to be retained in the clutch cover by not allowing that oil to flow to the drain plug area).

Every once in a while it is a good idea to remove the clutch cover to get the settled out grunge you'll find there (of course there IS also some settled out grunge in the center cases, so if you want to get it ALL you'll have to split the cases --- which would be a step toooooo far in my opinion).

There is certainly nothing wrong with doing a transmission oil change by simply draining the 16 oz and putting in 16 oz of fresh tranny oil for a "regular" oil change. (Let's not go international space station on regular maintenance, OK?) And since 16oz is 80 percent of the full capacity . . . I'm sure not interested in messing about with a vacuum pump to perhaps get out another 10%. The important thing here is . . . ANY regular maintenance is better than NO regular maintenance. So if the difficulty of striving to do a "perfect" oil change causes you to put off doing a run-of-the-mill 80% oil change . . . are things better or worse?

Ed