Blackdogdualsport.com Message Board

bike seemed to be running fine, rode it to work this morning not
problems. I had washed the bike after work and was about 5 miles down
the road when it started acting up. Giving it throttle it cut out and
at the same time put out a hugmungous cloud of smoke, totally
obscuring the highway. Rolled off the throttle a little and it cleared
and ran ok but give it the gas and the same thing happened. It ran OK
no noises cruising at around 50mph, no smoke. If I rolled off the
throttle more it would die, probably fouled plugs. If I gave it any
sudden throttle it would smoke and cut out.
when I got home I could see oil peeing from the airbox. Quite a bit
got pumped through there, enuf to drop the level from the top of the
sight glass to just below the middle.

Any ideas?

Vern,
Two things come to mind:

1: Oil level is overfilled. I'm sure you checked that, so probably not the issue.

2: Something blocking the airbox like a rag, sock or whatever. Your tranny breather tube no doubt goes to the airbox and if the opening is plugged, it will try to make up for it by sucking through the breather tube.

All I can think of for now.
-Tom
PS: no oil in the gas tank, or didn't add premix in there, right?

Tawmass wrote:Vern,
Two things come to mind:

1: Oil level is overfilled. I'm sure you checked that, so probably not the issue.

2: Something blocking the airbox like a rag, sock or whatever. Your tranny breather tube no doubt goes to the airbox and if the opening is plugged, it will try to make up for it by sucking through the breather tube.

All I can think of for now.
-Tom
PS: no oil in the gas tank, or didn't add premix in there, right?

1) not overfilled-it was at the top of the sight glass, right where i have kept it since I got the bike. It is now halfway down the sight glass and the oil was running out of the airbox. The oil is fresh with no water or fuel contamination that I can see.

2) I am not sure that makes sense, but I will check it. If the intake was blocked, wouldn't it act like a choke? Thats what seemed to happen when I gassed it, but I think that was from it taking a big slug of oil thru the carb. When I backed off the throttle it would run normally...

Good point - agree, it would choke. Okay, try this: take the tranny breather and disconnect it from the airbox (plug the airbox connect point if it's between the filter and venturi). Take 'er for a spin and see if it's the same thing, and/or see if it spews black gold all over your boot. Perhaps there's some sort of PCVish valve in there that's not working?
-Tom

Check this link:
http://en.allexperts.com/q/Motorcycle-R ... lter-1.htm

I know you're not on a Hardley, but the same idea. Check for a valve.
-Tom

Tawmass wrote:Check this link:
http://en.allexperts.com/q/Motorcycle-R ... lter-1.htm

I know you're not on a Hardley, but the same idea. Check for a valve.
-Tom

Yeah, but that explanation only works for separate oil, dry sump systems. I was thinking there might be some sort of rotary valve in the crankcase for the breather, but I am being told there is not.

Probably means I have a broken ring, but it doesn't really act like I would expect - not smoking all the time, seems to start and have power.
However , it doesn't idle and something must be pumping up the crankcase pressure....

Vern,
I doubt a broke ring would cause that much spewage. It would primarily lose compression and idle rough, hard starting, etc., but puking out that much spooge - don't think so...
-Tom

Just got back from Seattle-bought a very nice Red 2004 KLR with 1500 miles on it. I also bought a spare 650 engine. It's not stuck and i am cautiously optimistic. If I can swap it into the black bike and it proves to be a good runner, I can take the original motor apart at my leisure and see whats wrong with it. If the replacement turns out to be junk, maybe there will be enuf parts between the two to get something running...

going to swap the sidecar to this over the weekend and I will be sending you my BlackDog entry forms....

Ooh, it looks pretty red - and loud?
-Tom

I didn't think it was loud, but I rode it to work today and saw some kids at a bus stop covering their ears as I went by
Maybe I should take out a couple of discs....

That is a nice looking bike.