It's possible that the Mobil 1 initiallyused in these autosis a very thin viscosity, possibly some type of 'break-in' synthetic,and that each of these vehicles listed assertivelyrecommends changing the oil after 500 miles or so; I don't know.

I do know that motors are usinglighter oil these days because of closer tolerances.

These motors may also be pre-broken-in, as HOTLAP also stated.

 

The wife and I may have figured out what went wrong. We realized that the oil usage went way up right after we made the bike richer. We had it dynoed today so it is set correct. Will give it some miles to see if that took care of the problem. (Hopefully)

Can anyone explain why oil usage may go up if the bike is ran richer?

 

Don't know for sure, but I get (1200 SE Conversion with Stage 1 & Pipes) quite alot of oil into my aircleaner that goes right into the carb. Except it also comes dripping out of the air cleaner atmedium to highRPM. Rate is 1 quart per 1,000 miles. You will see oil spots on the rod covers if this is going on, and a drop on your right boot nearly every ride.

 

I may be wrong but I think recall seeing several dyno tests here on the Stage 1 1250 conversion with the HP in the low 70s. Yours shows 66?

 

The bike had the oil blow by right after we got it. Took it into the dealer and I believe they replaced the valve guides. Not a drop of oil has hit the filter since. Even after the conversion.

 

In a rich condiion, not all fuel is burned, it "washes" the cylinder walls of the oil, then it is exhausted out the tail pipe. Also, have yer wife check the Oil on a Hot engine, if she fills it to the upper mark on a cold engine, it is in fact "to full" and will burn the excess. Giving the false impression that it is using Oil. My 05 likes the level half way between add and full when HOT.

 

I know of no real reason why your bike running richer in the carb would make your bike use more oil, and I highly doubt that that is the reason.

Your bike just sounds like a typical engine that hasn't finished the wear-in process yet, and the rings haven't seated yet and that is the cause for your abnormal oil consumption.

This is typical, actually, and happens to all engines before the rings seat.

Until all the honing is rubbed off and the rings have seated, oil will get past the rings quite easily and burn in the combustion chambers.

If it's still doing it after 2000 miles or so, then in my opinion something might be wrong with the engine; and I say might, as sometimes engines can take longer than normal for the rings to seat, especially if the engine had a deeper than normal hone done on it, etc., or if the oil is synthetic or so forth.

BTW, what viscosity of oil are you using? Thinner oil will also increase this effect, especially thinner synthetic oil, which will deplete faster even in engines that are totally broken-in.

 

Okay, then perhaps that is a plausible explanation; I don't know, but it is certainly possible, but I still tend to think thathis rings haven't fully seated yet.

I've played with motorcyclecarburetor jetting numerous times throughout the years, running very rich mixtures and so forth as well as lean mixtures, and I've never noticed an increase in oil consumption because of any rich mixture; but perhaps anything is possible; I don't know. It seems to me though that is would take quite a bit of unburned fuel in the cylinder to do this, and I just can't picture that much fuel going through any little jets that would cause such a thing. But since I don't know for sure, I won't say that it is not possible. It seems to me, though, that this much fuel would end up in the oil then, and keep the oil level pretty consistent, unless it was evaporating or something; I don't know.