The wrong kind of smoke show...

[ZuminaZX]

Hello all. I recently purchased an 85' Vmax which expels white smoke from the exhaust pipes. I'm not quite sure what the problem is but here's a run down of the bike's over all condition: The coolant looks nice and clean and the level does not change. One of the float bowls leaked, but I have since replaced the gasket. The float bowl level in that carb was 1.5" or so. The bike itself idles and revs extremely smooth (I've owned an 85, a 92, and a 98 and this is by far the best running 'Max). I'm not sure where to look now, other than the carb needles. Maybe they've been shimmed?? The bike is all original and has just over 18k miles on it. Any input would be GREATLY appreciated!

 

[Buster Hymen]

Hello all. I recently purchased an 85' Vmax which expels white smoke from the exhaust pipes. I'm not quite sure what the problem is but here's a run down of the bike's over all condition: The coolant looks nice and clean and the level does not change. One of the float bowls leaked, but I have since replaced the gasket. The float bowl level in that carb was 1.5" or so. The bike itself idles and revs extremely smooth (I've owned an 85, a 92, and a 98 and this is by far the best running 'Max). I'm not sure where to look now, other than the carb needles. Maybe they've been shimmed?? The bike is all original and has just over 18k miles on it. Any input would be GREATLY appreciated!

I've got a couple of threads going about the same issue. One here http://www.vmaxforum.net/showthread.php?t=1622 and one here http://www.vmaxforum.net/showthread.php?t=1635 . Haven't found the answer yet, although I suspect a coil.

 

[ZuminaZX]

I had a similar problem on my 98 max and a new float bowl gasket solved the problem. I guess I'll pull the carbs again and check the level of each float. It might also be worn float needles.
I don't think the issue is with the ignition system as the bike runs so well and the tach is spot on.

 

[Buster Hymen]

I had a similar problem on my 98 max and a new float bowl gasket solved the problem. I guess I'll pull the carbs again and check the level of each float. It might also be worn float needles.
I don't think the issue is with the ignition system as the bike runs so well and the tach is spot on.

Pull all your plugs. When I have the smoke problem, number 3 cylinder plug is always wet. Otherwise it runs fine when it is not smoking. Mine is an intermittent problem, which I believe is the coil crapping out under load.

 

[ZuminaZX]

I'm going to play with it some more today. I'm almost certain the float levels are to blame. The previous owner said the bike ran perfectly until one day it began to smoke while he was out riding. I think the damaged float bowl gasket was the main culprit (fuel was leaking out of the float bowl and down into the intake boot), but the float levels made need to be adjusted after 22 years and 18k miles. I'll let you know how things go.

 

[maleko89]

I would go and replace all o-rings and gaskets since you have to break the float bowls open anyway.

Mark
#1098

 

[ZuminaZX]

I pulled the carbs apart earlier this evening. The floats are between 1.12 and 1.14. I guess that's a little on the lean side, yet the excess fuel keeps entering into the motor. Where to now?

 

[maleko89]

Did you check fuel level before disassembling? Did you check float movement? If they get caught that would cause flooding. How do the rubber cabs in the jet block look? Inspect the mixture screws too. How does your air filter look? Are you getting a decent spark? Vboost butterflies closed? How do the coasting enricheners look? Any holes in the C.E. diaphragms? Does the plunger move nice and smooth?

Mark
#1098

 

[ZuminaZX]

Holy vocab batman!
I have a new UNI filter, I don't know if the Vboost is working at all (see my other post), the floats move fine, the slide move freely, the rubbers on the jet block look fine, I'm going to check the spark once I get the carbs back on (the fuel pump spewing fuel everywhere prevents me from checking right now). On to the pics:

Here are the carbs when I first started. I was getting initial measurements of 1.22. I reset all of them to 1.115.

Here are the float needles themselves. They look pretty worn. If the float reset fails, these are for sure the problem.

Here's a shot of my Vboost linkage. Does everything look alright?

And here's a plastic peice that I lost track of during disassembly. Anyone know what this is and where it goes?

 

[shawn kloker]

That plastic piece goes over the water fill cap under the right scoop.Mine flew off on a test ride without scoops.Seems fine without it.

 

[maleko89]

Oh yeah, those float needle valves are really worn! I'd replace 'em all.

I see a bit of brown crap in the float bowls, might want to remove jet block and check gasket and holes to make sure everything is good. Check your manifold boots too.

Thanks for the pics!

Mark
#1098

 

[ZuminaZX]

That plastic piece goes over the water fill cap under the right scoop.Mine flew off on a test ride without scoops.Seems fine without it.

sweet, thanks.

 

[ZuminaZX]

what does a new set cost?

I took one jet block off, everything was clean and flowed fine. The brown stuff ended up in the bowl after I hosed the whole carb down with brake cleaner to remove surface grime.

 

[ZuminaZX]

Well I got it back together and the problem appears to be solved. It does not smoke at idle anymore, however it does smoke a little after its' been ridden hard. I think this has something to do with the fact that the previous ownersput all of 500 miles on it in the course of two years. There also might be a little gas in the oil, seeping past the rings.
I must say though, this thing moves OUT. The Vboost began to work yesterday and I'm almost certain this thing would bury my other Vmaxes! A brake upgrade (R1 brakes and SS lines) is definitely in order!
Also, I found complete carb rebuild kits for $140 at carbkitcapital.com. That price is for 4 kits which include new gaskets, needles, pretty much everything you'd need to completely rebuild the carbs.

 

[turbostang]

Well I got it back together and the problem appears to be solved. It does not smoke at idle anymore, however it does smoke a little after its' been ridden hard. I think this has something to do with the fact that the previous ownersput all of 500 miles on it in the course of two years. There also might be a little gas in the oil, seeping past the rings.
I must say though, this thing moves OUT. The Vboost began to work yesterday and I'm almost certain this thing would bury my other Vmaxes! A brake upgrade (R1 brakes and SS lines) is definitely in order!
Also, I found complete carb rebuild kits for $140 at carbkitcapital.com. That price is for 4 kits which include new gaskets, needles, pretty much everything you'd need to completely rebuild the carbs.

I would be wary of those kits until I can update u further. I think the jet sizes are inaccurate. I bought that kit overthe winter and still cannot get it tuned since it was installed. I will let you know if I figure it out over the weekend.