mobil 10w40 2hrs run time

harrisperformanc

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San Antonio
leaded race fuel used. Engine has in excess of 50 hours, and is raced at a local professional level. Engine shares transmission with engine oil. Doesn't look good!
 
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1,784
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Bonnyville, AB
The copper and iron numbers look fine (bearings and cams), the lead in the fuel is skewing the lead result, the aluminum could be from piston scuffing but it isn't a huge number. If it was a raced motor at a pro level, all of those numbers say to me it'll easily last the duration between rebuilds, but you might want to look for an oil that will stand up better to the gearbox. The silicon number also says the motor is getting good clean air which rules that out as a wear problem.
 

harrisperformanc

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Messages
5
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San Antonio
very often! I put two hours of run time, but I would expect that oil had no more than one hour on it. That's about one race day. thanks for above comments... (and the owner of this bike insists on mobil....so he runs it). Any suggestions for a better oil? I have actually been reading sunruh's stuff quite a bit, and it seems the cheapo's perform well. I have tried rotella T previously, and while I don't have any analysis to prove it, the oil drained at 30 minutes of run time (one pro moto) smelled horrible and the rider complained of shifting issues (he had no knowledge of the oil) so I have not used it since.
 
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2,689
Location
South Carolina
Synthetic not required for such short intervals. I cannot remember the website or company now, but their product focus was engines for racing bikes like yours and they strongly recommended straight SAE 40 or 20W-50 Schaeffers non-synthetic for best wear protection, yet economical enough for 1-2 hr oil changes. They said they had tested about everything out there and this had performed best in motocross single cylinders in racing or severe conditions. Sort of what sunruh found with Exxon Superflo, IIRC.
 
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449
Location
panhandle of florida
 Originally Posted By: harrisperformanc
very often! I put two hours of run time, but I would expect that oil had no more than one hour on it. That's about one race day. thanks for above comments... (and the owner of this bike insists on mobil....so he runs it). Any suggestions for a better oil? I have actually been reading sunruh's stuff quite a bit, and it seems the cheapo's perform well. I have tried rotella T previously, and while I don't have any analysis to prove it, the oil drained at 30 minutes of run time (one pro moto) smelled horrible and the rider complained of shifting issues (he had no knowledge of the oil) so I have not used it since.
I've had shifting issues with rotella as well. I'm not sure why people like it so much I haven't had good experiences with it at all.
 
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2,134
Location
Cedar Park, TX
since you say it is a shared sump, that limits this to a blue/yellow/green/orange bike. 1) your aluminum is worse than i've ever had, buy a large margin. 2) your iron is more than double my worst 3) copper is just fine 4) you need to clean that air filter more often or use a better oil on it! not a good value there. 5) you susvis and flash show why the 10w40s arent worth pizz step up and use a better oil!!!
 
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2,134
Location
Cedar Park, TX
fz1, my experiences show it would not matter. i have only have one (1) {the total number of fingers you pick your nose with} 10w40s stay in grade and at 1.6 hours it was just a hair from being out of grade. sae30s laugh in the face of 10w40
 
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East Central Missouri
 Originally Posted By: sunruh
fz1, my experiences show it would not matter. i have only have one (1) {the total number of fingers you pick your nose with} 10w40s stay in grade and at 1.6 hours it was just a hair from being out of grade. sae30s laugh in the face of 10w40
Do tell. Inquiring minds want to know. Seriously. Does a straight 30 grade work better for this application? Always thought that many of the straight 30's were a better idea for some air-cooled applications but didn't have any real proof.
 
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2,134
Location
Cedar Park, TX
every sae40 and sae30 i have tested has been in grade. i've run the major brands. the much vaunted (and for good reason) GC 0w30 also laughs in the face of 10w40s. 10w40 isnt a good choice
 
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434
Location
Arizona, USA
 Originally Posted By: sunruh
GC 0w30 also laughs in the face of 10w40s.
What is "GC" in that statement? I'll show my ignorance. I *think* the general issue with the 10W-40 is the spread between 10 and 40, and the proportion of VIs? If so, why would a 0W-30 (spread of 30, same as 10W-40) be any better?
 
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391
Location
OTTAWA, ON, CA
 Originally Posted By: TucsonDon
 Originally Posted By: sunruh
GC 0w30 also laughs in the face of 10w40s.
What is "GC" in that statement? I'll show my ignorance. I *think* the general issue with the 10W-40 is the spread between 10 and 40, and the proportion of VIs? If so, why would a 0W-30 (spread of 30, same as 10W-40) be any better?
German Castrol Shear resistance likely, compared to the average 10W40... Has anyone else ever thought that perhaps the engineers who designed the engine and figured out which oil to use factored in that a lot of 10w40's will drop out a grade and that a 30 weight is ideal for the engine/transmission? Or is that just crazy thoughts? Maybe I should ride more... my CBR125R specs a 10W30...
 
Messages
434
Location
Arizona, USA
 Originally Posted By: craigq
Has anyone else ever thought that perhaps the engineers who designed the engine and figured out which oil to use factored in that a lot of 10w40's will drop out a grade and that a 30 weight is ideal for the engine/transmission? Or is that just crazy thoughts?
Quite plausible. Honda changed their Goldwing recommendation from 10W-40 to 10W-30 with the stroke of a pen and absolutely no change to the engine.
 
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