What gear box oil?

[BigJack]

Well I just did a complete engine rebuild on my 01 KDX 200. I filled up all the fluids and it fired right up. Well I go to put it in gear and it doesn't go anywhere. I figure the clutch wasn't adjusted right. I adjusted it and it goes but doesn't hook up like other bikes I've had. I bought this bike broke as a project. I've ridden the bike around and it seems like the clutch may be slipping. Sometimes the clutch hooks up but most of the time it doesn't. I went to a local bike shop and bought what the jackass working there recommended. They didn't have a big selection. It's MTL Fluid 80 weight. It says it's wet clutch racing approved. Well the manual says to use 10-30 or 10-40 motor oil. I've also heard of using ATF. So what should I use?

 

[KX02]

The 80 wt. should be fine, I used to use 80 wt. I have now switched to type f atf. It's cheaper and works great.

 

[Rhodester]

I believe the manual recommends 10W-40 motorcycle specific oil.

When my clutch started to slip a little I put in ATF. It cured the slipping pretty quickly since it has super detergent properties. After awhile my tranny resisted upshifting out of 3rd gear (to 4th). I drained the ATF (type F) and put full synthetic in and that cured the shifting problem....and it still doesn't slip anymore. My theory is that the ATF cleaned the glazing that had developed on the clutch plates, but is not the best lubricant.

 

[Zerotact]

ATF, when ever it stops looking red in the sight glass, I slap another $1 on the autozone counter, and put new fluid in.

 

[Feanor]

I use Redline 80wt synthetic, its expensive (additionally because I change my oil after every ride) but I look at it like cheap insurance, like changing your air filter often. Also, with clean oil the clutch action is just that much more consistent over the entire days ride than if you leave oil in there longer.

I've never tried ATF... but I'm going to look into it...

Feanor

 

[BigJack]

Thanks guys....

 

[kdxiowa]

I use MOBIL ! sythetic deisel oil 15/40 in mine never had a problem with slippage or shifting. It has better wear characteristics than automotive oil and more boron and zinc which is good for the gears. Just my $.02.

 

[redramhemi]

Belray gear saver 90 wt. never a problem

 

[Sunny State KDX]

I'll second the redline hypoid gear oil. brutal expensive but good stuff. I was recommended to use it in my old shifter kart. The stresses we put on those trannies is far and above what dirt bikes see. Actually in a kart we only trash the gears as the clutch is almost never used (only for standing starts) where on dirt bikes the clutch takes alot more abuse.

I've also used ProHonda trans fluid in the past and never had a problem.

 

[Kwakasaki]

I guess i am old school. I use the kawasaki Chemspec oil and it works just fine.

 

[wpriest]

If this was a new clutch, I would have to ask if you soaked the clutch friction plates in oil before assembly the unit. The friction plates are like a sponge and need to be full of oil before exposing them to the frictional forces that a clutch must stand up to.

 

[Jaybird]

You are far ahead of the game by concentrating on changing your oil out more often, than worrying about what oil to use.

Moto specific oils are a waste of money, as there are suitable oils available for far less.
Type F ATF is my choice for a 2-stroke engine.
Most of the scare folks have about friction modifiers and clutch slippage is unfounded.
More often than not, problems with a clutch is a mechanical issue and not attributed to oil choice.

Using a full synthetic is a good idea if you tend to heat the bike up with your type of riding, as synthetic base stock can take heats over and above that of what a dino oil can withstand. However, never use synthetic in an attempt to lengthen your change frequency. Always change out early and often. Getting rid of metal particulate is far more important than oil choice.
Never wait until you see your fluid change color to change out. Damage has been done by that time.

 

[BigJack]

Nope clutch is not new. I bought the bike with a bad engine. I rebuilt the engine and noticed that there were several different types of oil being used. The clutch does feel better. It may be that clutch needed to get used to the new oil. I'm sure the previous owner didn't use the same kind. I've got a couple of liters of this stuff so I'll try it until I run out and then maybe try ATF. Thanks guys.