best drive belt length for ZX trans?

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AIO MotorSportS
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best drive belt length for ZX trans?

Post by AIO MotorSportS »

best drive belt for 97mm variator and 118mm torque driver?

675-17.5-32 malossi for dio zx
703-17.8-30 polini for sfx50 AF37
705-18-30 malossi for AF37
738-18-30 for RH50,yamaha,minarelli
:jack:
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Wheelman-111
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Re: best drive belt length for ZX trans?

Post by Wheelman-111 »

Greetings:

Best for general, acceleration, or top speed?

Malossi ZX belt is hard to beat. A 669mm uses all the downgear and accelerates best. A 654 will split the rear pulleys and run fastest on top, but doesn't accelerate as well. A Met 661 splits the difference, but may need a few miles to break in. The angle is 28 degrees.
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"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
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Re: best drive belt length for ZX trans?

Post by AIO MotorSportS »

thanks,,do you know if the plastic fan on vario kit racing planet sell for a Kymco 50,GY6 50 could be fit on AF16?I'm looking and I think may be could be made it work,good swap to cooling down the trans :)
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Re: best drive belt length for ZX trans?

Post by LMH »

That fan does nothing for cooling. Most intelligent people with the gy6s remove them. It may move a small amount of air around but it is negated by the extra drag on the crank.
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Re: best drive belt length for ZX trans?

Post by AIO MotorSportS »

LoveMyHonda wrote:That fan does nothing for cooling. Most intelligent people with the gy6s remove them. It may move a small amount of air around but it is negated by the extra drag on the crank.
for you words I assuming you are ready try it?and fit AF16?,and you don't see any difference on vario/belt/torque temperature with or without the fan?and you lose performance or rpm on engine because the fan? thanks.
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Re: best drive belt length for ZX trans?

Post by Wheelman-111 »

Greetings:

The belt-drive transmission seems to be pretty-much trouble-free as delivered. Even on high-output 72 and 82cc builds, the trannys seem to stay together until the belt wears out. So there really isn't any pressing need to "Improve" them. If you're really worried about cooling the sheaves and belt, just run without the rear cover. Unless the fan has a fresh-air intake and a way to exhaust the heated air, it really won't do much.

I just noticed that in your original post you are asking about specific belts for your oversized 118mm rear pulley. I'm pretty sure no one else has reported installing that sheave, so direct experience will be hard to find. If the ZX pulley is 108(?) mm, and you're adding 10mm, then 3.1416/2 cm. should be added to the belt sizes in my responses. (Half of the added diameter) for a pretty good educated guess. So a 685mm belt should be about equivalent to a 669 on a 108mm rear pulley.

You definitely want to get all of the 18mm of width, but if you go much longer I predict it'll slap around and fray the outer belt covering, leading to premature delamination and failure.
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Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
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Re: best drive belt length for ZX trans?

Post by AIO MotorSportS »

hi W111,Now you got it,yes the diameter of rear pulley is 118.5mm(pics),well... if nobody try it yet may be I have to spend some money on belts and try out.and the fan too...I'm a :crazy:
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Re: best drive belt length for ZX trans?

Post by AIO MotorSportS »

The way i like is keeping both covers,thats because awant to try intall the fan and make a scoop
On the front case to get flow from front and let it go on back(pic) :)
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Re: best drive belt length for ZX trans?

Post by LMH »

The fan is not pitched, it will not move air like you are thinking. The blades are flat at 90 degrees with 0 pitch. The will add weight to your over all balance and slow your engine speed down. I have done it on my tao tao but you had to use a different outer castle gear. I can send you a gy6 drive face and fan but you will need to find the castle and nut to make it work on the af style. I enjoy your enthusiasm but I think that fan mod is futile.
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Re: best drive belt length for ZX trans?

Post by PtRoughneck »

That fan will blow up! Seriously don't put it on your bike. Keep stick fan.
.
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