Malossi Belt size belt verification

[Zino]

I am building out a Genuine RoughHouse and the stock belt comes up a little short .

I am trying to verify Malossi Belt Specs .

I measure them by rolling along a table to verify there length like this 

www.youtube.com/watch?v=K7oGuQLrGzs&ab_channel=PartsForScooters

If you could help me get a handle how far they are off before i order 7 belts to find one that will fit .

[df41590]

My 6112741(has <50 miles it) is 787.4mm(L), 16.7mm(W), 8.75mm(T from tip of peak) according to scootertuning supposed to be 796mm(L), 16.5(W), 8mm(T).

[geoffh]

That's how I measure belts now,but I use masking tape on the edge of my bench and piece of tape on the belt to mark it with a pencil,I have no malossi belts but I do think we should compile a list of known belt lengths using this method from the real world of our garages not parts listings,I am a long way from a math guru but we have fixed points of reference and travel(ignoring wear and tear) there must be an equation that would work??.

Geoff

[Zino]

Bando belts give true measures
I just measured a 738 bando belt and a 758 bando belt by rolling along my bench .

[90GTVert]

Brand new 6111108. Lists as 815mm. I measured 805.2mm.

Looking at the measurements above of another Malossi belt, it looks like about 1.2% shorter than spec. Not a huge data set though.

Malossi belt length ÷ 1.012 = Rolled belt length

Examples :
6111108 : 815mm ÷ 1.012 = 805.3
6112741 : 796mm ÷ 1.012 = 786.6

Not right on, but close enough. If we had some big list of Malossi rolled lengths, maybe it would come out to something better or at least be verified to work in many cases.

On the flip side, if you know the Bando length and they are indeed true to rolled length, then...

Bando Belt Length x 1.012 = Malossi Belt Length

[fugaziiv]

I enjoyed making that video with Tom. I'm glad it's still helping.

We find that Bando and Gates measure out correctly to what they print using this method. Polini and Malossi generally do not.


Matt

[90GTVert]

Measured more belts.

Malossi 618779 lists as 820 length. I measured 807.7. Still comes out fairly close using 1.012 mentioned above.


I also had some Bando belts.

Bando 788. I measured 787.4.
Bando 878. I measured 876.3.
Bando 669. I measured 668.


I had one Gates belt. I've never been a fan of those. I ordered a 798 Gates to replace a 788 Bando years ago and the 798 was shorter. Don't have that one anymore, but I do have a 788, which is shorter than the Bando 788.

Gates 788. I measured 779.8.

[Zino]

Thanks Brent,df41590,
That 1.012 formula might be the ticket.
I have a polini belt that is speced at 750 but rolls out to 738 .
Trying to find upsize compatible belts is challenging.

[Zino]

polini 248.003
specs off scootertinung 16.7 x 750 x 30
rolled it out to 738 x 16.7 x 30
polini belt 248 .041 specs per scootertuning 17.5 x775x30
rolled out to 760 x 17.5 x 30


Top performance belt
specs are 777x16.5x30
It rolls out to 777

[FrankenMech]

The belt length is actually the length through the 'tension cord' of the belt. Rolling a belt along a table will be close but not exact. However it is usually close enough to identify a replacement. Used belts will stretch during operation. The sides or friction faces will also wear causing used belt width to vary.

All that black dust inside the CVT is worn from the friction faces of the belt, some of the wear dust is lost through the vents.

The guy in the video mentioned has a fixed stare and glassy eyes. I suspect he is in the the process of turning into a zombie. Measures must be taken to protect yourself from zombies.

[Zino]

piaggio long belt measurements

malossi part number 6116424 765x18x30 measures at when rolled out 750x18x30
dayco part number vc31191 756X18x30 measures when rolled out to 745X18X30

[davybondo]

2002 BWS
OEM old belt is a Yamaha 3AA-17641-00 measures 737x14.95mm wide 8.5mm deep
Artek belt #1738, 759x16 8.1 deep and it measures 750x16.5 8.1mm deep that's 9mm short scootertuning
Athena belt #S410000350001, 16.5x8.1 deep 751 long
and it measures 16.3x9.19, 741 long thats 10mm short scootertuning

[davybondo]

Scooter Tuneing.ca
Mitsuboshi Hyosung 772x16.5mm
real size is 761x16.2 wide by 8mm deep
Model: VC30920

[TheScooterJesus]

Jun 14, 2021 14:04:33 GMT -5 Zino said:

I am building out a Genuine RoughHouse and the stock belt comes up a little short .

I am trying to verify Malossi Belt Specs .

I measure them by rolling along a table to verify there length like this 

www.youtube.com/watch?v=K7oGuQLrGzs&ab_channel=PartsForScooters

If you could help me get a handle how far they are off before i order 7 belts to find one that will fit .

if i wanted more acceleration for wheelies would i want a tighter or looser belt?

[90GTVert]

Jan 20, 2024 12:53:10 GMT -5 TheScooterJesus said:

if i wanted more acceleration for wheelies would i want a tighter or looser belt?

You want the right belt. A tight belt, at least the way I think of it, sounds too short. Bad for gear ratio on both ends. A loose belt, or again the way I'd think of that, would be too long. When the belt is too long, there's slack. From my experiences trying longer belts than I should have used, it runs poorly till it takes up the slack. Then there's also the risk that it could be pushed off of the pulleys. Generally, what you want is a belt that can sit against the drive boss while being at the outer edge of the rear pulley with some tension on it at rest.

The other way that I think of tight or loose belts relates to contra spring pressure and roller weight. You want stiff/heavy enough parts there to control the belt so it doesn't have excessive slip, but going much tighter than needed will likely result in a reduction of performance and potentially greater wear.