Possible buy...

[Kirtie]

Hello all, and Happy Mother's Day to whom it may apply!

I am negotiating with a guy for a 78 XS11 with around 25k miles on it. The bike is in SPECTACULAR shape, and is 100% complete (right down to the hidden kick start pedal).

Here's the catch: he had one of the petcocks leak on his bike over the winter and was unaware of what to do, exactly. (AAIIEE such a shame...) So he has his old man, who is a mechanic, repair the petcock (whether or not it was successful is immaterial at this point...) and slaps the whole thing back together and rides it to work (a couple of miles).

On the return trip, it starts smoking like heck and quits. After sitting a little while it starts again but is smoking badly. (These are his words.)

Well now the guy is moving and wants to sell his bike. I went there to look at it knowing that he had some trouble with it, and of course the first thing I did was pull the filler cap and sniff the crankcase: GASOLINE.

What are the odds that the rings are still OK? It has good compression, or at least seems to by the way it turns over. He rode it straight home and shut it off and that was that. I haven't heard it run: I'm going to co-pay for some oil and volunteer a little time to drop and change the oil and see how it is.

Any thoughts? I'd really hate to have to spend $$ on a rebuild kit the instant I bought the bike, but it's utterly immaculate and I can't see it go to someone else...

[DiverRay]

DO NOT spend any money until the bike is YOURS!! There have been many people try to "fix" a bike BEFORE the purchase, only to have the owner say "thanks" and keep the bike. If he does not want a huge amount for it($750 or more), then buy it and go from there. Usually if it's smoking, you have oil in places you shouldn't have. Once it gets into the exhaust, it WILL smoke for a while.
Your call...

[rpgoerlich]

If your mechanically inclined and can afford the purchase, I'd buy it.
BUT Negotiate...Title, Tires, Tank, Seat, Brakes, Engine, ect...

Smoking could be alot of things. Overfilled crankcase with fuel and oil could make it's way into the exhaust. Mine took 4 hours to burn off... Petcock could still be letting fuel by the diaphram into the intake making that cylinder run rich.

[b.walker5]

Did he say what colour the smoke was?? Blue or Black. Black smoke is fuel and probably easily fixed, blue smoke is oil and could be moe serious.

[TopCatGr58]

Smoking isn't necessarily as bad as KNOCKING! Hopefully he hasn't spun any bearings. Having only ridden it a few miles, hopefully local streets and not highway speeds, that he may have not put much stress on the engine, and that the bearings are okay? Overfilled crankcase and diluted oil can easily get blown into the airfilter chamber, back into the intake, etc.!!

You should be able to talk him down by espousing that the gas in the crankcase could have damaged the crank bearings, and a total tear down could be involved, etc., and that could help bring the price down!?
T.C.

[skids]

I wouldn't even consider it until an oil change is done. Would you have to ride it home with thinned contaminated oil? Then do a compression check. If it is not knocking, compression is even (+/1 10%) then I would consider getting it, but turning off the fuel to prevent oil contamination is important. Specials can be turned to Off (if even that works). Standards will need forceps or a golf tee in the fuel line to stop the flow when not running until the petcock and the needle valve in the leaking carb is fixed. This could definately be a negotiatiation factor in the price. If a real mechanic would do the work with real replacement parts, it could cast at least a couple hunderd $$

[DGXSER]

Negotiating points

If gas is in the oil, then it was not the petcocks alone that were leaking
As Skids eluded to, that bike has at least one carb float valve that is ALSO leaking. This will require you to pull the carbs and go through them completely.

As has recently been posted here, an oil change could be $110 just in labor, I do not want to know what pulling the carbs and going through them would cost.

I agree with the consensus, run a compression check on it. Should be around 142 psi + or minus 10%. I've read on here of folks running decent with as low as 110-120 psi, but should be +/- 10% across the board in my opinion. IF it is low or one shows to be low use the couple tablespoons of oil in the cylinder test to see if it is rings. If compression goes up, it is rings.