This Oil Any Good For My 450?

6 replies to this topic
  • zracer196

Posted February 04, 2006 - 03:07 PM


I am SURE this has been beaten to death...

But I thought I'd ask anyway...Just bought an 03' LOW hour 450. The guy at the shop sold me Castrol R4 Superbike 5W-40 oil. Fully synthetic. Any good? The previous owner used Motorex (sp?).

I have roadraced (still do) for over 10 years and have always used off the shelf Mobil 1. NEVER a problem in ANY of my racebikes...

Can I use Mobil 1 or should I keep the Castrol...What weight for Florida?

Thanks in advance!

Here is what my ride has...Bought it from a fellow TT member.

Bike as follows:

2003 YZ450F with approximately 15 hours on it.

Full service just completed, all fluids changed, all filters cleaned.

RG3 woks suspension

RG3 shock and fork coatings

Pro Taper bars

RG3 upper and lower triple clamps

Renthal Gold chain.

Stealthy flywheel weight

FMF carb jet kit

Brand new Michelin tires

Hinson Clutch

Ride engineering hot start switch

Works connection clutch with perch

Works connection protective guards

  • 642MX

Posted February 04, 2006 - 03:09 PM


Did you do a search?

  • DRH

Posted February 04, 2006 - 05:40 PM


Yamaha originally did not recommend synthetic oils. Too slippery for the clutch. Since Yamahas uses the same oil in both the engine and transmission they wanted the petroleum based stuff.....Its cheaper and one is more apted to change it more frequently.....I've always used the Yamaha oils and the bike has fared well. 7 years old with no major failures. Clean oil is the secret...

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • Jeff_Ashe

Posted February 04, 2006 - 06:16 PM


Go to WalMart and buy Rotella-T Synthetic. $12 per gallon. Or run the Mobil-1 Red Cap if you can find it. You are in Florida and will be fine. The only problem I have seen is Mobil-1 does not shift well in cold weather because of the heavier viscosity.

  • Butta

Posted February 04, 2006 - 06:50 PM


I second the Rotella at WalMart, but not the synthetic stuff. I use the Rotella 15w-40 and change my oil every 4-5 hours. I don't think you need to spend the extra $ on synthetic, since it doesn't stay in there long anyway, and something to be said about a wt ratio of less than 3 (15:40) versus the 5w 40 (ratio of 8), meaning the synthetic 5w-40 relies on the properties of the viscosity index improvers for it's characteristics when at temperature. Since I warm my bike up before romping on it, I'm not concerned with the cold viscosity number.

Grayracer can explain it much much better... :thumbsup:

  • Jeff_Ashe

Posted February 04, 2006 - 06:57 PM


I agree that dino blends work best for most. I use synthetics because around here we get several months of 85F and above and humid. Synthetics just look better coming out after a hot day's run. I change every race week. Heck, most people could resell my used oil for new!

  • grayracer513

Posted February 04, 2006 - 07:25 PM


The guy at the shop sold me Castrol R4 Superbike 5W-40 oil. Fully synthetic. Any good?

It might be perfectly fine. In fact, as an engine oil, I'm sure it's more than adequate. The question is, can it survive being a gear lube?

Synthetics are a much better choice in general for motorcycle oils for a variety of reasons. The oils that you should avoid are those labeled API Energy Conserving II (EC II). Such oils could (not will) cause the clutch to slip. OTOH, oils labeled JASO MA are certified compatible with your clutch. There are lots of good oils that aren't either of these, and they seem to work alright for a lot of people.

Butta, you did a pretty good job with Viscosity Index Improvers. Just to clarify, all multigrade oils use them, but those with a wider spread between their base weight and their operating viscosity use more of them. The problem is that unless an oil in primarily formulated to be used in a transmission/engine combo, the VII's will not be of a quality able to withstand the bashing they get, and the oil will shear down out of grade in a fairly short time.

But oils do exist that won't shear out of grade. They make multigrade gear oil, right? It costs more, though. The best two oils I know of from this and other standpoints are Amsoil Synthetic Motorcycle Oil (MCF or MCV) and Mobil 1 MX4T. Both hold their viscosity remarkably well, and the Amsoil is actually labeled API GL-1 in addition to the engine oil grades it carries, making it a legitimate transmission lubricant.

The Castrol should be OK, but until I saw a used oil analysis, or the results of a Shear Stability test (ASTM D-6278), I wouldn't go more than 5-6 hours between changes with it.

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