Maintenance Questions

[2-Stroke Tom]

Hi All. I just got around to getting a 2004 KX500 I bought a few months back ready for a ride out in the desert tomorrow. I noticed that when I went to drain the oil, it was black (not from being dirty), and was nothing like the 10w30 the manual recommends. My 500 was a Team Green race bike with a lot of modifications, so factory specifications may or may not apply. The bike had Maxima sponsorship stickers, so I imagine their gear lube was in it.
 
Can I go wrong with just using Castrol 10w30? Just to note, I think the bike may have steel clutches and a Hinson basket.

Also, the spark plug was a NGK B9EVX. I think the engine was done by Varner Motorpsorts, but I'm not aware of their modifications. Does this spark plug sound like it's in the ball park? Thanks in advance.

[hughes]

10w30/10w40 would be fine. I perfer ATF Type F but that's another topic. I would flush the gear box of the other oil and to do that I would refill the gear box start the bike and take a short ride (down the street and back) drain it one more time and then refill. I have never seen black gear box oil unless it was burned up and used up. Even if your bike was a team green bike it could have gone through a few other people before you got it unless you bought straight from team green.

[2-Stroke Tom]

Thanks for the information hughes. I rode the bike today for a couple hours, and everything seems to be working great with the Castrol 10w30. The bike hasn't been ridden for  quite some time, but the motor was rebuilt and suspension was redone by ACME before it sat in a garage for a few years. It fired right up and ran flawlessly, so I was happy to see no leaks or any other issues. I'm not sure if it was Team Green's modifications, my lack of 500 experience, or just the fact that it's an almighty KX500, but I was pretty impressed by the power of this bike today. The bike is geared at 15/45, and it rips all the way to top speed like nothing!

As far as the NGK B9EVX spark plug, I found out this is what Team Green was running when the KX500 was still in action for professional desert racing. This bike was taken out of the racing circuit in 2005, and I think it had the same plug in it that it was retired with! I think NGK B9EVX is now replaced by BR9EIX, but I will have to verify.