2009 Zuma w/ polini hi-speed variator -- belt length

drumstyx
Scoot Member

Posts: 55

2009 Zuma w/ polini hi-speed variator -- belt length Apr 20, 2022 10:13:23 GMT -5

Quote

Post by drumstyx on Apr 20, 2022 10:13:23 GMT -5

another silly question!

What are you Zuma folks running for belt lengths? The OEM belt that came in this thing was the listed-spec 738mm, but seeing that I was nowhere near the outside of the rear pulley, I put an Athena 751-16.5 on it...I'm still a good 4.5mm from the outside of the rear...

I'm watching those homemade overrange variator videos on youtube, and I notice that his Minarelli "clone" engines are using 788 belts, which I see are stock for the 4 stroke Zumas.

I ran a fabric tape measure around the belt as-installed, to verify its length at 751 -- yep, that's legit. I've got it shimmed pretty well perfect so the belt is just about touching the variator boss, so I ran the tape measure along the belt at the front, but around the outside of the rear pulley, and came up with 765mm, which is stock on some Peugeot scooters apparently. Unfortunately, I can't seem to find a North American supplier of these belts, since I don't think we've ever had Peugeots in North America.

One thing to note: this belt is 8.1mm thick, so while I don't mind a thicker belt, if my math is right, I'd need an extra ~3mm in length per 1mm extra thickness.

How the heck is 49ccscoot running a 788 on a Minarelli? I guess our engines ARE different though, since my CVT cover doesn't have a support bearing.

Any ideas for a good belt length here?

THE FLEET
2009 Yamaha BW's (Zuma) 50: Stage6 Sport Pro MKII, Yasuni C16, 21mm CP, MHR overrange, 14/42 primary/3.666 secondary, MHR Delta clutch
2013 FJR1300
1997 KLR650
1982 Honda C70 Passport
1978 Honda CB750K
1997 Yamaha BW's (Zuma) 50
- Polini Corsa
- Stage6 crank
- Yasuni R
- 19mm PHBG
- Stage6 Variator 5g
- Stage6 hard torque spring
- stock primary/2.6:1 secondary/10.4:1 total
- Malossi fly clutch

ryan_ott Scoot Master! Posts: 5,195	2009 Zuma w/ polini hi-speed variator -- belt length Apr 20, 2022 10:21:25 GMT -5 via mobile Zino likes this Quote Select Post Deselect Post Link to Post Member Give Gift Back to Top Post by ryan_ott on Apr 20, 2022 10:21:25 GMT -5 You’ll find some good choices in here: 49ccscoot.proboards.com/thread/24543/top-performance-td-belt-length
	2008 Yamaha Zuma 2008 Metruck 2019 Yamaha MT07 1994 Yamasaki - RD250 swapped Ninja Flip over and eat sh*t

drumstyx
Scoot Member

Posts: 55

2009 Zuma w/ polini hi-speed variator -- belt length Apr 20, 2022 11:15:50 GMT -5

Quote

Post by drumstyx on Apr 20, 2022 11:15:50 GMT -5

Apr 20, 2022 10:21:25 GMT -5 ryan_ott said:

You’ll find some good choices in here:
49ccscoot.proboards.com/thread/24543/top-performance-td-belt-length

OOOOO yes this is a great read, thank you! I see you're the OP on that one -- you mentioned a 764mm belt for an Aerox, but I can't seem to find that (at my canadian vendor at least). Got a link? Part number even? Any vendor that'll ship to Canada would work, just that North America is better on shipping

THE FLEET
2009 Yamaha BW's (Zuma) 50: Stage6 Sport Pro MKII, Yasuni C16, 21mm CP, MHR overrange, 14/42 primary/3.666 secondary, MHR Delta clutch
2013 FJR1300
1997 KLR650
1982 Honda C70 Passport
1978 Honda CB750K
1997 Yamaha BW's (Zuma) 50
- Polini Corsa
- Stage6 crank
- Yasuni R
- 19mm PHBG
- Stage6 Variator 5g
- Stage6 hard torque spring
- stock primary/2.6:1 secondary/10.4:1 total
- Malossi fly clutch

benji
Scootaholic!

Posts: 3,154

2009 Zuma w/ polini hi-speed variator -- belt length Apr 20, 2022 15:23:13 GMT -5 via mobile

Quote

Post by benji on Apr 20, 2022 15:23:13 GMT -5

Apr 20, 2022 10:13:23 GMT -5 drumstyx said:

another silly question!

How the heck is 49ccscoot running a 788 on a Minarelli?

there are several motors minarellis made, including 3 (at least) different versions for Yamaha/MBK. Jog style is considered a short block, and runs a longer belt due to the final drive configuration.

Just be glad you don't have an Eton.

05 zuma w athena bbk, polini For Race 4, 21mm pwk, malossi OR, 14/42 gears, aerox wheels, aerox brakes, steel braided lines, Derbi gp-1 master cylinders, rear disc, 32:1, Malossi fly clutch w black springs, lightened OEM flywheel, advanced timing, naked voca bars, yellow hids, smoked clear tail, aerox cf front fender, no rear fender, viper strike tires, lowered "2, side stand, all stainless hex bolts, black mica '08 plastics w '02 belly pan, recovered seat.
'87 elite
'88 elite sa50

ryan_ott
Scoot Master!

Posts: 5,195

2009 Zuma w/ polini hi-speed variator -- belt length Apr 20, 2022 21:20:58 GMT -5 via mobile

Quote

Post by ryan_ott on Apr 20, 2022 21:20:58 GMT -5

I’m not sure what the number for that 764mm belt was. Here is a list of belts. Maybe you can find a good match in there. I do know what belt you’d need with the 122mm pulley..
webmotors.hu/shop_ordered/2914/pic/meretek/Scooter-belt-catalogue-Dec-09-1.pdf

2008 Yamaha Zuma
2008 Metruck
2019 Yamaha MT07
1994 Yamasaki - RD250 swapped Ninja

Flip over and eat sh*t

Zino
Scootaholic!

Posts: 3,910

2009 Zuma w/ polini hi-speed variator -- belt length Apr 20, 2022 21:42:59 GMT -5

Quote

Post by Zino on Apr 20, 2022 21:42:59 GMT -5

With the polini variator and malossi variator .
I actually got to 2mm left with a stock belt .
The right size shims and just the right weight of weights .
With a street pipe or Stock pipe I was 6 grams with the polini and above to get the travel.
With the expansion pipe tecnigas next r and yasuni r I was between 5 and 6 grams .

Manufactures measure belts difference I prefer to roll them out
Here is a thread where we discuss belt lengths
49ccscoot.proboards.com/thread/28919/malossi-belt-size-verification

His and Hers 2004 Yamaha Vinos malossi bbk malossi wild lion, multi var polini green clutch springs 6.5 gram sliders 50 mph
2004 Yamaha Zuma 58 Mph Sport Build Sold
2019 Roughhouse Malossi Variator 6.5 Gram Sliders NCY Clutch NCY medium clutch springs Ncy Soft Contra Malossi Mhr Replica BBK Wild Lion Exhaust Dellorto 17.5 90 main 34 pilot 52mph

nickatnight
Scoot Newb

Posts: 1

2009 Zuma w/ polini hi-speed variator -- belt length Jan 19, 2024 15:41:51 GMT -5

Quote

Post by nickatnight on Jan 19, 2024 15:41:51 GMT -5

Apr 20, 2022 15:23:13 GMT -5 benji said:

Apr 20, 2022 10:13:23 GMT -5 drumstyx said:

another silly question!

How the heck is 49ccscoot running a 788 on a Minarelli?

there are several motors minarellis made, including 3 (at least) different versions for Yamaha/MBK. Jog style is considered a short block, and runs a longer belt due to the final drive configuration.

Just be glad you don't have an Eton.

quick question, why should he be glad he doesnt have an eton? sincerly an eton owner

benji
Scootaholic!

Posts: 3,154

2009 Zuma w/ polini hi-speed variator -- belt length Aug 6, 2024 21:07:42 GMT -5 via mobile

Quote

Post by benji on Aug 6, 2024 21:07:42 GMT -5

Jan 19, 2024 15:41:51 GMT -5 nickatnight said:

Apr 20, 2022 15:23:13 GMT -5 benji said:

there are several motors minarellis made, including 3 (at least) different versions for Yamaha/MBK. Jog style is considered a short block, and runs a longer belt due to the final drive configuration.

Just be glad you don't have an Eton.

quick question, why should he be glad he doesnt have an eton? sincerly an eton owner

etons typically have slightly odd cvts, so it could be tough finding aftermarket parts for em. Iirc, you can't get a malossi over range for em.

05 zuma w athena bbk, polini For Race 4, 21mm pwk, malossi OR, 14/42 gears, aerox wheels, aerox brakes, steel braided lines, Derbi gp-1 master cylinders, rear disc, 32:1, Malossi fly clutch w black springs, lightened OEM flywheel, advanced timing, naked voca bars, yellow hids, smoked clear tail, aerox cf front fender, no rear fender, viper strike tires, lowered "2, side stand, all stainless hex bolts, black mica '08 plastics w '02 belly pan, recovered seat.
'87 elite
'88 elite sa50