Gear Drive better than Belt Drive?

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Even though the rear drive design has been in use for several years Yamaha made changes in the '06 FJR drive.

https://www.yamaha-motor.com/sport/parts/home.aspx

Looking at the "Drive Shaft" page for the '06 FJR shows the following changes:

Part# 13 gear coupling

Part# 16 bearing housing

Part# 33 drive shaft (longer swingarm requires longer drive shaft)

Miscellaneous other changes.

The bearing housing change appears significant.

 
Unlike those unbreakable, never-wear-out driveshafts, u-joints, ring and pinion gears???
Oh so true - I guess - but

I've had a few BMW's with nary an issue - anybody whos ever had a problem with a shaft drive raise ur hand -

For that matter - who ever has had a problem with a belt raise ur hand -

I've had 6 Beemers in past 6 years and have had 2 rear drive failures, both on K1200LT's and lost one rear drive seal on GS. At one point the K1200LT group figured that 4% of all LT's were having rear drive failures. We gave BMW NA a big yellow chicken in honor of them not addressing the problem on the LT's.

Doug Hines

 
Unlike those unbreakable, never-wear-out driveshafts, u-joints, ring and pinion gears???
Oh so true - I guess - but

I've had a few BMW's with nary an issue - anybody whos ever had a problem with a shaft drive raise ur hand -

For that matter - who ever has had a problem with a belt raise ur hand -
I've had 6 Beemers in past 6 years and have had 2 rear drive failures, both on K1200LT's and lost one rear drive seal on GS. At one point the K1200LT group figured that 4% of all LT's were having rear drive failures. We gave BMW NA a big yellow chicken in honor of them not addressing the problem on the LT's.

Doug Hines

There was a BMW at this years 1088 (not sure who the rider was or what model), Bike had less than 600 miles and the rear end fragged! :blink: Left a big oil stain in the hotel parking lot! :lol:

 
Of course, the other side of that is my son's `94 R1100RSA with 100k+ and no probs with the rear end. Same-ame my `02 R1150RSA with 47k.

 
Chains are the most efficient, but only if they are within proper adjustment specs, pivots in good shape, and the sprocket teeth are not overly worn. Few chains meet these criteria. For the masses, belt drive is best up to about 100 hp/tq, except for the occasional rock between the pulley and the belt (I've lost three this way). Otherwise they last for 50k or more.

Personally, I like shaft juut fine.

 
Chain drive - most efficient, most maintenance

Belt drive - not quite as efficient, not much maintenance

Gear drive - least efficient, almost maintenance free
Chain drive most efficient? You sure? And why would a belt, which has no moving parts, be less efficient than a chain, which has what...216 moving parts for a 108 link chain? And all those moving parts, the rollers, lose efficiency the second they do their jobs, i.e., roll. Since there is no "perfect" lubricant, those rollers are never rolling at 100% efficiency and even freshly lubed, they lose efficiency with every pass over the sprocket until they need lubing again, which only restores their efficiency to a fraction of their "new" efficiency level, and degrades quickly 'til they need another lubing again.

And besides the lack of moving parts with the belt, which essential needs no lubrication, or can be considered "self lubricating", isn't the stress friction, basically the contact point between the drive medium and the drive and driven pulleys, spread out more with a wide belt than a narrow chain? I'd love someone to calculate the PSI of a 1/8" wide chain roller at point of contact with the driven sprocket and compare that with the contact PSI of a 1 inch wide belt contacting the driven pulley of an equally weighted and powered motorcycle under similar acceleration.

Gear drive - least efficient. Yep. Almost maintenance free - man, you need to define "almost". If almost means maybe once in a million years, I'll give you "almost maintenance free". Otherwise, it still beats hell out of a chain, but doesn't really surpass a belt.

Finally, so as to not beat this to death with opinions, which of the three would you prefer replacing when/if they go tits up? A chain, along with its countershaft and rear wheel sprockets, a belt with same, or a driveshaft, u-joint, pumpkin, ring and pinion? Factor in cost and labor.

I figure a belt wins. Costs pretty much equal to chain, but no special tools needed to install.

Oh, one final + for a belt over both chain and shaft. Much, MUCH quieter. Never heard a belt grind like a chain or whine like a shaftie.
*******************

I think Jestal made my clarified my point for me..later.

Jay

'04 FJR 1300

 
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