Confirm my gray transmission oil suspicion

I have been maintaining my CR250 & my two sons CR80's for a number of years. I change the transmission oil at least every two rides and most times the oil comes out only slightly darker than it went in which shows normal clutch wear.

Recently my 15 year old has become quite an aggressive rider on his '01 CR80 and the oil has become VERY dark gray after only one afternoon of riding on an intermediate mx track. He has learned that feathering the clutch and keeping the rpm's up coming out of turns has helped his riding greatly. Every week now I also have to adjust the clutch cable at the engine side as there isn't enough adjustment at the clutch lever end and I'm almost out of adjustment on the engine side.

So my suspicion is that the dark gray oil is from the stock aluminum clutch plates wearing away. I say that because of the constant adjustment I have to do to keep proper clearance at the clutch lever side. Have you seen this before?
I'm using Mobil-1 15w-50 synthetic oil in the transmission.

Would steel clutch plates work better as a replacement for the OEM aluminum plates such as EBC sells as a clutch replacement kit?

Your thoughts?

Thanks for your opinions!

I have an EBC clutch replacement on order. My son will be riding a Hare Scramble in a couple of weeks and I don't want to be caught short before a race.

The kid is just WAY faster than me these days. Maybe because he's 35 years younger than me... :D

Thanks again!

thomas123

The Mobil-1 15W-50 synthetic oil is a Non Energy Conserving (Non-EC) oil that does not contain the friction modifiers that "EC" oils do.

You can tell an "EC" oil from a "Non-EC" oil by looking at the back of the oil bottle. In the lower portion of the API circle it will state "Energy Conserving" or be blank. Non-EC oils will be blank.

btw - I have used Type-F ATF in the past also with good results.

No Hand

I believe that may be what started the problem. My son didn't realize the clutch was slipping because of a tight cable (lack of free play) since he was having such a good time. There is sufficient free play remaining and I have it adjusted properly now but I can tell the disks are getting thin.

Good catch!