what are the pros and cons of each?what are the differences?how do they work? which is most reliable?
Thanks

 

Havent you asked just about every utility question possible?

Polaris and yamaha are a little heartier, but the kawi is much easier tuned. Zuki leans more towards the yamaha.

 

The theory behind them is the same. The drive and driven pulleys adjust their diameters to fit rpm and load.
Its in the details, in how they are different.
The polaris , while at idle and in gear, has the drive pulley open far enough for the belt to go slack. This allows it to idle in gear at a standstill, but causes separate problems, related to engine braking. There are cogs, like on a cam belt, on the id of the belt, and those cogs grab the mateing indentations in the drive pulley, when the pully opens up at idle. It will provide engine braking, but not instantly, at throttle off. And because the pulley opens, and the belt is slack...when going power on, the drive pulley suddenly closes, on the belt, and because of the mechanical advantage of gearing, can be tough on belt life...if the tranny is in high. Thats why its recommended to be in low, while doing slow driving...the mechanical advantage of lower gearing, allows the pulley to grab the belt, with less slipping and heat and wear.
The duramatic( suzuki) and ultramatic(yami) are very similar, to each other. The belt on these trannys are always in tension on the drive and driven pulley. It never goes slack. Which means, the only time you go to low range is when you want to. Theres no requirement to be in low range for going slow. Theres no sudden gripping of the belt , with power on, and no heat and wear either. There is a centrifical clutch, on the end of the crankshaft, which disengages the drive pulley at idle. This lets it idle in gear at a stop. The centrifical clutch only works when power is on. For engine braking, there is a sprag clutch, which is a one way clutch. In one direction, it free wheels(power on), and when the tires drive the motor(power off), it provides the link to give almost instant engine braking. Belt life is higher and noise is less with either of these two trannys.
The artic cats with suzuki motors, have the duramatics, and the 650 has the kawi system.

 

great pics hondabuster. I like the old 71' 70cc

 

I think simple is better.

 

The only problem, and it's not really a problem, I've had w/ my Vinson, is after a "high speed to zero" stop. If I don't ease back into the throttle, before rippin', the clutch make a little howling noise before engaging. Oh, and the damned thing rattles a lot on rough downhill runs. No performance problems, it just took a little bit to get used to it. I've had it in MAJOR slop and experienced ZERO slippage. Today's autos ain't the Polaris' of yesteryear (slip slidin' away)!

 

Does the vinsons tranny make a loud clicking noise if you slow down really fast? My Eiger does.

 

all those transmissions are garbage when compared to honda's transmissions. all those belts somewhere along the line will slip, break, squeal or whatever they do. junk if you ask me...

 

Except that it only cost $40 or less for a belt rather than $1000+ for a non-serviceable transmission. Face it, belt drives are here to stay!!

 

Bigbad scrambler It appears that we are both on the same side of the coin for once, Honda producing a non serviceable trans. hmmm that sounds closer to garbage huh.