Rear Pumpkin Temperature?

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So has anybody else felt to see how hot the rear case is?

After the change to the super duper oil from Yamaha, it is still almost too hot to touch!

 
Same here, I occassionaly put a finger(s) on the rear gear after a long ride, and too have experienced very warm conditions (I wouldn't say hot). I am currently using Valvoline synthetic 75-90 and have experienced no problems, not that I expect any. The very warm conditions, I experience, is considered normal operating temperature in my opinion.

 
A rear end specialist (uh oh, that's going to go in the wrong direction on this forum).

A differential specialist, (nope can't say that, it's not a differential).

Got it!

A ring and pinion specialist that I know says a new ring and pinion will run hotter than a well broken in one. Seems when new, the contact between the two gears is not always 100% causing localized hot spots. You will probably see lower temps as it breaks in more, but they all get hot. That's probably why Yamaha puts the black stuff (graphite or molybnium)(sp?) in the final drives from the factory, to aid in break in.

 
Hell I thought this was a cooking thing :blink: I was gonna say the pumpkin (or whatever) pie in the back always gets done faster (higher temps due to the solid wall in the rear of the range, versus the glass slightly insulated door), But....

As you were gents :rolleyes:

:jester:

 
My JFR's pumpkin will glow red in the dark after an extended high-speed ride. My tires and rims will, too.

If you're using a spec lube and the thing turns freely when on the center stand in neutral, I wouldn't worry about it.

IRBR

 
So has anybody else felt to see how hot the rear case is?
After the change to the super duper oil from Yamaha, it is still almost too hot to touch!
My BMW final drive was as hot. When you think that you're pumping anywhere from 50-140HP through it it should get hot. Also since there's only a small amount of lube in there the only way the heat generated can get out is through the metal case. On some race cars they actually cool the oil in the dif.

Ditto what everyone said about the special extra slippery Yamy Lube. My dealer sells both Yamaha and Honda and his mechanic told me that since they service both they just use the Honda brand for all the bikes. They do have Yamalube products and do sell the final drive oil. I bought a quart of Amsoil. The main thing you need to watch is the GL service rating and viscosity of whatever you use.

Comquats on the other hand can be used as fork oil but you have to run them through your blender first.

AZ

 
You know that power loss shown by the difference between crank HP and rear wheel HP?? Yepper, some of it is dumped by the final drive. That energy turns up as heat. Chains are more efficient, that's why they transfer more power and don't get hot.

-BD

 
So has anybody else felt to see how hot the rear case is?
Yes. After any length of time riding it's too hot to touch and hold.

After the change to the super duper oil from Yamaha, it is still almost too hot to touch!
Too hot to touch is normal, that's the way it is. Nothing wrong there. Move along folks. :)

It will be hot whether your using cumquat's, Mobil or the super dooper rip of priced Yamaha ****. And if your using anything priced over what Mobil 1 gear oil will run ya then your paying WAY too much for final drive (not differential) fluid. I guarantee there is nothing special about the Yamaha oil over any other decent synthetic other than the price.

:)

 
That's why its better to live where Odot came from. You can park outside and it stays pretty cool eh? PM. <>< :rolleyes:

 
Valvoline Syntec 90-140 gear oil. One liter will last 4 to 5 changes. The drive gears are doing well with it. I change the oil every other oil change. The oil still looks new when I drain it out.

 
Once, when I had just gotten back from a ride, my dog took a whiz on the pumpkin and it was so hot that it instantly turned to steam and burned his whizzer. He's an old dog, but he learned not to do that trick any more. But then I thought it was an anomaly, so I whizzed on it after a long ride. My dog was right: you don't do that twice.

 
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