GL-5 / Hypoid gear oil

[07Ninja250]

Looking for the best oil to put in the final drive on my 96 Virago. It calls for an 80W GL-4.

I'm a fan of Redline gear oils (MT90 in my car) and picked up a bottle of Redline Lightweight Shockproof gear oil. The description says: "Similar to a 75W140 gear oil, but with the lower internal friction of an SAE 30 motor oil." Their gear oils exceed GL-5 ratings.

Is this going to work ok in my bike? Shockproof doesn't mention anything about hypoid gears. However, Redline's gear oil tech info states the following about their gear oils, which I assume applies to the Shockproof products as well:

The natural lubricity of the polyol esters provide
excellent slipperiness which reduces the sliding friction
in hypoid gears - reducing wear and significantly reducing
temperatures.

Anyone care to help easy my mind?

[acergremlin]

When i had the XJ650 yamaha recommended GL-4 for the shaft drive, i was going to use GL-5 as it looked better spec. After a bit of googling it came to light that GL-5 spec oil deos not like yellow metals like bronze and it will damage them, so as i could not be sure as to wether the final drive contained bronze or not i stuck with GL-4.

[07Ninja250]

That's one point I've been trying to research. Thus far all I've found is that the rear-ends don't contain any yellow metals- ring, pinion & bearings - steel.

It is an oil that I'd hesitate to use in a synchronized transmission due to corroding danger to the synchros...plus, GL4 is just better in that application anyway.

Just trying to make sure the oil will take care of the hypoid gears (if that's what's really back there - wouldn't they just be regular bevel gears?)

[acergremlin]

Well i have heard it called a bevel box but never been certain what the difference was, until i found this site.

hypoid gears

So it appears benel gears are straight and hypoid gears are curved.

[acergremlin]

Just had a look at an exploded view of the xj650 final drive and it would appear they are hypoid gears, the middle gear drive is a bevel gear set but that is taken care of with regular engine oil.

[07Ninja250]

I guess I'm confused about the difference between hypoid and spiral-bevel.

Here's what I'm finding:

A hypoid is a type of spiral bevel gear whose axis does not intersect with the axis of the meshing gear.

Bevel gears are gears where the axes of the two shafts intersect and the tooth-bearing faces of the gears themselves are conically shaped.

Having read these two statements, I don't see how the final drive could possibly be a hypoid setup. I know the transfer case in my All-wheel-drive Mazda is a hypoid setup, but that's a completely different animal than a differential or final drive on a bike.

Anyone?

[acergremlin]

Well going by the exploded view i looked at the the link i put in the earlier post, i would say that the final drive is definately hypoid

[07Ninja250]

yep..you're right. Non-intersecting, yet still perpendicular.

[Dave @ Red Line]

Originally Posted by 07Ninja250

Looking for the best oil to put in the final drive on my 96 Virago. It calls for an 80W GL-4.

I'm a fan of Redline gear oils (MT90 in my car) and picked up a bottle of Redline Lightweight Shockproof gear oil. The description says: "Similar to a 75W140 gear oil, but with the lower internal friction of an SAE 30 motor oil." Their gear oils exceed GL-5 ratings.

Is this going to work ok in my bike? Shockproof doesn't mention anything about hypoid gears. However, Redline's gear oil tech info states the following about their gear oils, which I assume applies to the Shockproof products as well:

The natural lubricity of the polyol esters provide
excellent slipperiness which reduces the sliding friction
in hypoid gears - reducing wear and significantly reducing
temperatures.

Anyone care to help easy my mind?

Ninja250,

The MTL closely matches the 80W GL-4 gear lube that is being called for and is our recommendation. The ShockProof LightWeight would also perform well in your final drive.

A high offset hypoid ring and pinion would require a GL-5 extreme pressure gear oil and typically is referred to as a Hypoid gear oil. Your final drive doesn't contain a high offset hypoid ring and pinion, the pinion axis isn't offset from the ring gear center line so doesn't impose the extreme pressure requirements on the gear oil so wouldn't require a GL-5 gear oil as confirmed by Yamaha's GL-4 recommendation.

Please feel free to contact with any questions.

Regards, Dave
Red Line Oil