Oil Choice

I have an 2006 YZ450F. Of course, I was informed by my Yamaha dealer to use Yamalube 4-R Semi-Synthetic 10W-50W oil. My friend uses castrol 20W-50W oil that he purchases at Autozone. He recommmends changing the oil frequently vs. buying expensive oils. What does everyone recommend? What is the best weight?

I have an 2006 YZ450F. Of course, I was informed by my Yamaha dealer to use Yamalube 4-R Semi-Synthetic 10W-50W oil. My friend was uses castrol 20W-50W oil that he purchases at Autozone. He recommmends changing the oil frequently vs. buying expensive oils. What does everyone recommend? What is the best weight?

I don't want to sound like a dick, but try the search (upper right) there has been a ton of threads on oil.

IMO after reading most of them it's kind of a tossup. I started with a cheaper Rotella, and started wondering why, hell I have a new bike, why take any chances. Now I use Amsoil 10W-40, better safe that sorry.

For the yami, I hear that guys use the Rotella T. I am not sure about the Castrol - Since yamahas have the engine and clutch fluid combined, the oil cannot have some friction modifiers.

I am sure that Grayracer will jump in any minute and save the day (he's usually all over oil questions). Also, he will tonuge lash you for not using the search feature either. This topic has been covered many times over and over

the *ONLY* thing you need to follow is this:

pick an oil that you can afford to change every 3 hours or less.

there are very few that can actually last 3 hours.

and yes, the search button will should about 6 trillion posts on this subject.

For the yami, I hear that guys use the Rotella T. I am not sure about the Castrol - Since yamahas have the engine and clutch fluid combined, the oil cannot have some friction modifiers.

I am sure that Grayracer will jump in any minute and save the day (he's usually all over oil questions). Also, he will tonuge lash you for not using the search feature either. This topic has been covered many times over and over

I am aware of the "Savior". He has helped me plenty. Grayracer....please be kind. I did search, but to no avail. Should I keep spending $10.00 a quart for the Yamalube?

I am aware of the "Savior". He has helped me plenty. Grayracer....please be kind. I did search, but to no avail. Should I keep spending $10.00 a quart for the Yamalube?

Yamalube for $10.00 a quart? Holly shit gray is going to love that.

Mobil 1 Racing 4T 10w-40 made just for thumpers. $8 per quart at Autozone.

After reading alot of opinions on this website I have recently settled on Rotella Synthetic from China Mart. It seems to be the best combination for money and protection. But believe me, just start reading the threads here and you might wish you had never asked!

After reading alot of opinions on this website I have recently settled on Rotella Synthetic
A good oil while it lasts. Change it often.

Gray, thanks for the linky to the amsoil research.

Some really interesting stuff there about shear resistance etc etc..

Will ber changing very often or using mobile 1 4MXT (sic.) not sure about the letters. Since we don't have amsoil here and motul is hard to find..

Chage often is what I think I am down to. I was going to try the diesel oil I mentioned on another thread but the graphs in the amsoil pdf really got me thinking. cheers..

OK, as long as we're on that subject, there is a way to get low cost oil that will retain it's viscosity.

In this post:

http://www.thumpertalk.com/forum/showthread.php?p=4465322#post4465322

(the second one linked above) I discussed shear down and Viscosity Index Improvers. These additives, and the inability of those used in many engine oils to withstand use in a transmission are the culprit in viscosity loss in motorcycles most of the time. It's important to understand why they are there.

Multigrade oils (like a 10w-40) start out as a 10wt base oil. We want the oil to be "thin", or very pourable, when it's cold so that it will get to the lubricated components as fast as possible. But 10wt is way too light an oil at 200 degrees (F), so something has to be done. That's where VII's come in. They prevent the 10wt oil from thinning out as it heats up as much as it ordinarily would, so that at 200 degrees, it still pours at the same rate that a 40wt oil would at that temperature. Now we have a 10w-40 oil. But when the VII's get beat up by the trans, or anything else, they no longer do their job, and the oil does thin out with temperature more like a 10wt would.

The best way around this is to use the sturdier, more expensive VII's used in gear oils, as Amsoil did with MCF and MCV, and Mobil with V-twin and Racing 4T (MX4T). But the cheap way is to use a straight grade oil. A straight 40wt is a straight 40wt, and needs no help from additives to do that. That rather obviously means that there is no way for the gear box to beat up the additives that aren't there, and the oil will be a 40wt for a much longer period of time.

The downside? You don't get good cold engine oil circulation from straight grade oils, so you need to be more respectful during the warm up period than most people seem willing to be, for one thing. For another, it's hard to find a good synthetic in a straight 40wt. Not impossible, but you'll have to look.

OTOH, you can buy a good quality petro or blended oil in a single grade very cheaply, most of the time, and change it in 6 hours or less instead of 10 hours or less, and that could solve your problems.

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