Because car oils are not engineered for motorcycles, especially the high HP, high revving engines in todays bikes. Plus, two very reputable motorcycle engine builders told me so. Dave, it really comes down to what you like and feel comfortable with. I personally use Mobile One oils in all my engines. Motorcycles, truck, ATV, and lawn mower. Never had an issue with any engine relating to oil. I know you and others out there swear by Shell Rotella T, but it's not for me. If don't use Mobile One Racing T4, I'd use Amsoil Synthetic Motorcycle oil. And, I may start using it in my next new bike anyway, I think it's that good. http://www.thebestoil.com/motorcycles.asp?engine=adwords!1502&keyword=(motorcycle+oil)&match_type=
Any oil wears out faster in a bike than a car. That much is true. BUT, no oil is immune from this. The greatest bike oil in the world still breaks down faster in a bike than it would in a car. That does not mean that you should only use 'bike' oil. The same thing happens to it in a bike as any other oil. All you are hearing is hearsay. Even if it comes from reputable engine builders. They may have more experience building engines, but even if they had an engine or two blow up, that is hardly a scientific test. They are not necessarily in a position to know that one oil or another helped or hurt the motors. All they have is happenstance, and a reputation. People listen to them, but on something like this, they are guessing just like everyone else. I say, prove it! A annecdotal story or two won't cut it. We have plenty of annecdotal stories of bikes running with car oil with no problems whatsoever. So those stories cancel out the 'horror' stories. And we still are left just guessing. As long as we are just guessing, and there is no real proof that car oil is in any way bad for a bike, why not get a good cheap oil and be done with it. Oh yeah, because the advertisers have us scared. They put the fear of 'cheap' into us, so they can sell more expensive 'motorcycle' oil. I don't know about you, but I am leary of advertising claims. Especially widely disputed ones like the claims for 'motorcycle' oil.
This is why I have my oil analysed on a regular basis. I want to actually _know_ what's goin' on with my oil. Speculation is useless. On that note, I sent out the oil from the TLR on Wed. so I"ll post when I get results. IT's Rotella-T, and was in there for the Barber race weekend, (1) track day, and all of the GNF. I was gonna sent the oil from teh SV after the endurance too, but Rod changed it for me when he redid the motor...that one will have to wait 'till next year.
I'm not skeered to part with cash, I gladly shell out >$20 a gallon for Rotela or DelVac full synthetic at Petro or Flying J. It keeps my Mercedes 450HP 13-liter running as well as my 636's and Mille. I only have to carry one type of oil for everything I run! While basestocks may be te same, I do know from experience the friction modifiers and additive package(s) called out by the API and SAE in the latest gasoline automotive oils have caused wet clutch problems is "some" bikes. While this seems rare, it might be something to consider. Also the automotive oils and the related specs do not address the shear loads motorcycle transmissions and clutches place on them as no car I know of shares a common lubriation system with transmission and engine. If the same oil was best for both, automakers (and the SAE and API) would call for the same to be used in both crankcase and transmission, correct?
Whatcya up to Dave? And to think I have spent many night in te Wal-Mart parking lot a mere set of automatic doors away these savings!! Looks like Wally World it is from now on.
STT-GUY said...If the same oil was best for both, automakers (and the SAE and API) would call for the same to be used in both crankcase and transmission, correct?[/QUOTE] My 91 CRX calls for 5/10-30/40?(one of those) in the transmission and IIRC my 95 YZ250 had an either/or specification for the gearbox(MTF or a specific weight) I read alot of this oil stuff years ago on usenet and what I got from it all was that if you are changing it even semi frequently and not operating under "severe" conditions you can use inexpensive oil of the correct grade. Ran various cheapy stuff through a 95 CBR for 55K miles, cams looked like new at the 48k valve check. Changed oil when transmission started feeling a little funny going from 1-2, generally 5-6k miles. Bike did see some track days and quite a few days at the drag strip. Original clutch/tranny working fine when sold. The cam chain tensioner, however, that is a different story... As always, YMMV
Count me in on running 'truck oil' in my race bikes. I stumbled across another of the oil threads last year or so & tried the plain Rotella (15w40), using the 'I change it pretty often' rationale. It works just fine, I run at least two race weekends per (Sat & Sun practice, 2 Sun sprints), if it's not getting dark I may leave it. Also usually only change the filter every other oil change (as recommended by the owner's manual). All this in oil-cooled GSX-R's (1052 & 750) where the oil really is the lifeblood of the engine. One time I went so far as to take the oil from the bike & put it in the truck! Works great, get about 7k miles between changes on the truck-it does get pretty dark, though. Truck is 5.9l gas Dodge. The correct viscosity is the most important thing. And making sure the level is correct, too.
Another vote for Rotella. 4 bikes in 4 years it is what I've been using. I don't even bother with synthetic, 8 bucks a gallon is right down my alleyway.
Rotella for me too. The Ford short bus, Focus, Taurus, and both R6's, the previous GSXR...and the MZ...it was actually John Deere branded oil, but then I found out that Shell was the actual manufacturer of the oil. Shell Rotella oils have "C" designations for diesel use. Diesels hammer their oils by forcing them through a lot of orifices at high pressure. High RPM's aren't a problem. After I drain my oils, I screen them, and then I put them in the diesel tank on the short bus to use as fuel. Can't do it in the cold months, but when it gets warmer, no problem, synthetic or dino.
i was told that the rotella has too many detergents and could actually do harm to a motorcycle motor. i was also told that the rotella was designed more for diesel motors. just what i was told.
Detergent.... Perfect for keeping wet clutches clean. Designed for Diesels.. Yep, it's true. Just happens to be that Diesels hammer oil. They force it through the engine at very high pressures so the oils contain an additive package that increases the oils ability to withstand these forces and maintain viscosity. With this in mind, now imagine what your transmission (all those gears and the clutch) does to the oil it SHARES with the engine. This is exactly why we use Rotella in our bikes with excellent results. In a perfect world, we'd use one oil for trans and one for the engine but then we'd be riding Harleys which are not on the cutting edge of performance or leading edge of technology.
that does make sense monte! and i am just forwarding what i have been told. you here so many theories and ideas on the oil thing. it's hard to really justify any of it. my manual said just do not use oils with moly. so i stick to the HP4 without moly and haven't had any issues. it's probably packaged next to the pennzoil car oil like rugbymook said earlier.
I used Mobil 1 before the new API/SJ ratings for fuel efficiency pomted them to put a friction modifier in it that "can" cause wet clutches to slip. If I had a Duc, I'd still use it (dry clutch). Truth be told, I have used most everything out there, mixed brands, and done just about everything else you're "not" supposed to and I have never had an oil related failure. I do change it on a semi-regular basis in the bikes but I'm not a fanatic. With two strokes, I have always used Yamalube and am really superstitous and won't switch... BTW - We're out in Utah and I just picked up an 06' Kawisaki KLX-250. I'm having a blast!
