KDXRIDER.NET

Hey all i just picked up a 1993 kdx 200 a few months ago.

It's got ufo plastics as well as some kind of aftermarket headlight that i'm trying to find bulbs for haha.

Anyway, this machine is only on it's second piston so it's just stock besides that. I've had it on some good rides, it runs real strong!

I had it out today though and after riding i noticed that the bike now makes a whining noise coming from the lower part of the engine. It whines higher if i give it some rev and then it's hard to hear if i'm riding at speed.

BAsically if i start the bike up and let it idle you can hear the whining noise and then when i give it rev u can hear the whining noise and it sounds like it speeds up almost. I have had the bike wound out a couple times to make sure it's running good and everything but i don't run it all the way out all the time.

Any advice on what could be wrong? The bike still runs just like it did before only now i have a noise. sounds like it's supercharged but it's not haha.

Checked your clutch oil lately?

i actually just changed it but i rode it a couple times after i changed it and didn't notice the noise. I put 10w40 in there. just regular oil.

Regular oil has friction modifiers in it and can cause your clutch to slip. Especially older clutches.

ok, would this still be happening when it's just at idle and not moving? I mean this happens when it's sittin on the kickstand and i let it idle or give it a little rev i can hear the whine.

If you think it's the clutch, what kind of oil should i put in there?

thanks for the quick replies!

also just to be clear....the clutch oil is the same as the gear oil right? the only oil on this bike that you can change correct?

just wanna make sure i'm not missing a seperate oil somewhere.

I am not saying that's what it is but it is somewhere to look. You should use oil made for wet clutches. You can get it at any bike shop.... 4 strokers share engine and clutch oil so it should be redily available.

Your clutch is always spinning and slightly engaged even in neutral, only free spinning with friction when it encounters resistance.

But like I said... I am not saying that's what it is but that is somewhere to look.

Yes... the clutch oil is the only oil in the bike other than your premix in the gas.

I run regular 10w-40 in my KDX250 and my CR250. I change it every 2 rides. What Inda is talking about, is that most regular oils have a friction modifier. If you use an oil with that, it will not perform well. There is a seal on the bottle that will tell you if it has it or not. A lot of guys run ATF with good results. I just stick with oil cause it works for me. Remember though, that I change mine Often!

Ok so should i run atf oil or should i just get me some honda gn4 and run that?


I think i'll do the honda first and see if my noise goes away. It sounds like it's coming right from the under the kips. Where the power wire goes into the case on the left side of the bike is where i can hear it the loudest.

maybe it is the kips noise?

I've used silkolene in most my other bikes but I used to do a lot of sand riding and always had good luck and only changed the gear oil every 8 rides or so and never once had any trouble. Also I bought a rm250 from a buddy 4 years ago that made a weird whining sound and would kind of rev up on its own turned out to be the crank bearings and seals I just junked that thing would have cost more then it was worth to fix

I have good luck with ATF type F. Use either that or a wet clutch specific 10w 40 motor oil.

mercenary223 wrote:I've used silkolene in most my other bikes but I used to do a lot of sand riding and always had good luck and only changed the gear oil every 8 rides or so and never once had any trouble. Also I bought a rm250 from a buddy 4 years ago that made a weird whining sound and would kind of rev up on its own turned out to be the crank bearings and seals I just junked that thing would have cost more then it was worth to fix

i'm thinking mine could be the crank bearings the way it wines. It's not that hard to fix though i don't know why you would have junked it.

the kips rattles supposedly, this is not a rattle this is a whine and it's not coming from the kips it's coming from down lower.

Right, bottom end rebuild

rod kit $80
crank bearings/seals $50
and $50 in labor

You also need a gasket kit. Good thing to have anyway though. Sounds like laziness rather than expense.

The parts were cheap but the shop wanted a arm and a leg to do the work and I was to scared to split cases.

there's really nothing to it

I hear a whining noise when I ride my KDX, but it usually becomes more noticable when I get home.

kywoodsrider wrote:I hear a whining noise when I ride my KDX, but it usually becomes more noticable when I get home.

LOL
That whining noise happens even with the engine off ??

With the engine off is the only time you can hear it.

do you guys think i should run it like this at all or fix the problem asap?

i ordered a complete gasket kid with oil seals on ebay. I've gotta get the rod kit and bearings now.