Bike: 2003 KDX 220.
It's been a while since I've posted on here, or even been on my KDX. Last weekend, finally got the bike out and went riding. Before going, I changed the transmission oil. (Yes I did refill the oil). After we got home, I happened to glance at the sight glass and noticed I couldn't see any oil!
Any suggestions of common problems to look at first?
On another bike (not a KDX) I had the seal around the shaft for the front sprocket leak. I'll start there unless y'all have any better ideas
It was definitely cold. It was the next day after the ride. The back half of the case looks dirty like oil collecting dirt. But it didn't seem like it was coming from one specific spot.
Yeah. It did. My wife was riding the bike for a while and I was following her. I noticed a fair amount of smoke, as if it wasn't warmed up. I figured it was because she was riding below the powerband and I mixed the gas rich (more oil). For simplicity sake, I mixed 24 oz of oil in 6 gallons of gas. I believe that's close to 60:1.
More oil in a fuel mix is called leaner, as there is less gasoline. 24 ounces of oil to 6 gallons of gas is 32:1.
With the motorcycle held level, make sure it is in the middle of the sight glass. Go ride for a while. Check the oil level after 30 minutes or so with the bike horizontal, check it again. If it has lost oil, then it is time for a vacuum test and / or pressure test. DO NOT just start splitting the cases.
Ok. Thanks for clarifying that. How does one go about doing a vacuum or pressure test? Is a vacuum test done differently than a pressure test?
I really appreciate everyone's input. I'm going camping this weekend and won't be able to work on it until Monday. When I do get to it, I'll post pictures as needed.
How much oil did you put in it when you changed it? I had a similar issue with my 220 I changed the oil then filled it up via the site glass. After a few rides I checked it and it was not registering on the site glass at all. Spec is 700ml and but i only put 300ml and it looked full but it was not.
morganid wrote:Ok. Thanks for clarifying that. How does one go about doing a vacuum or pressure test? Is a vacuum test done differently than a pressure test?
I really appreciate everyone's input. I'm going camping this weekend and won't be able to work on it until Monday. When I do get to it, I'll post pictures as needed.
I would say if it's smoking more than normal and running poorly it may be your RHS crank seals sucking in gearbox oil into the combustion chamber.
Ok. Back from the camping trip. Here are some pictures to explain:
Day after our ride, I left the bikes on the trailer and put the trailer in the garage. I know my front fork was leaking so I figured the oil I saw on the trailer was from the front fork. Then the next day, I noticed a small pool of oil on the ground, I assumed it was also from my fork, but I happened to look at my sight glass and notice no oil. In this picture, the tongue of the trail is on the ground, and there is no tension on the straps. https://www.flickr.com/photos/145768230 ... res/U43R95
Boxfresh25 wrote:How much oil did you put in it when you changed it? I had a similar issue with my 220 I changed the oil then filled it up via the site glass. After a few rides I checked it and it was not registering on the site glass at all. Spec is 700ml and but i only put 300ml and it looked full but it was not.
That is really good to know. I only filled it using the sight glass. I have no idea how much oil I actually put in. Monday or Tuesday, I'm going to start working on hunting down the issue. This is now on the list of possibilities.
Brinkman wrote:I would say if it's smoking more than normal and running poorly it may be your RHS crank seals sucking in gearbox oil into the combustion chamber.
It was smoking more than normal, but I wouldn't say it was running poorly. I was riding with my wife. I have very little reason to push it into the power band. When I did, it would get there, but take a sec to "clear it out" before the power hit. I figured it was due to the extra oil in the gas and riding below the power band so much.
Boxfresh25 wrote:...but i only put 300ml and it looked full but it was not.
Never fill by sight glass. Know exactly what amount your pouring in. However, having said that, just pour in a full quart (.946 liters) and be done with it.
Jason wrote:is this hose the transmission vent tube, which is supposed to be routed up to the airbox
morganid wrote:Yeah. It did. My wife was riding the bike for a while and I was following her. I noticed a fair amount of smoke, as if it wasn't warmed up. I figured it was because she was riding below the powerband and I mixed the gas rich (more oil). For simplicity sake, I mixed 24 oz of oil in 6 gallons of gas. I believe that's close to 60:1.
Jason wrote:is this hose the transmission vent tube, which is supposed to be routed up to the airbox
No. I believe that is the coolant overflow. I know for sure, the transmission vent hose is present and routed to the airbox as it should be. However, I'm just now realizing that vent isn't filtered. It's just stuck in the airbox before the air filter.
morganid wrote:Yeah. It did. My wife was riding the bike for a while and I was following her. I noticed a fair amount of smoke, as if it wasn't warmed up. I figured it was because she was riding below the powerband and I mixed the gas rich (more oil). For simplicity sake, I mixed 24 oz of oil in 6 gallons of gas. I believe that's close to 60:1.
Do you have it jetted for 60:1?
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No. I don't know what it is jetted to. I've used a few different ratios. I just happened to have a full 6 gallons of fresh gas and so I bought two 12 oz bottles of Golden Spectro premix oil and dumped em in.
I drained the oil from the transmission to see how much was in there. Looks like about 300-400 ml. (Put it back in a bottle to measure it). I was surprised how dark it was already. I'd call it a gray color with a red tint. The oil started red.
I had a bottle with 800 ml so I put all of that in.
Gave the bike a quick rinse with water to get the dust off and some carb cleaner to get the oil/dirt off. I then took it for a 10 minute ride around the neighborhood. I didn't spend much time cleaning it, but it was enough to show me if leaks appear. Doing that, I found a handful of areas that were significantly more caked with oil/dirt than others. In particular, the rear of the case by the swing arm.
The bottom of the case doesn't look like it is too bad except towards the rear of the case as mentioned above. There was the smallest amount of a glisten around the flange on the drain plug bolt. It could have easily been water. Tried to dry it as much as possible. It could be a very small oil leak. Ever seen the threads leak from a drain plug???
Sight glass still full after the 10-minute ride.
I recently have replaced all the drain hoses off the carb. It's possible that some of the oil that has caused the caked-on areas is from the carb hoses being cracked...
So I think I just didn't add enough oil in the first place. But It's still possible I have some leaks at various places. As far as I can tell, none of them are big enough to cause as much fluid loss as what would have been required to cause the original potential problem. Probably just chalk this one up to operator error.
Thanks all for your help!!! If there are any updates, I'll post them.
Last edited by morganid on 02:25 pm Jul 10 2018, edited 1 time in total.
