Widening variator for new belt Vivacity 2T AC

[morphex]

Hi.

I have a new belt that is jamming and choking the engine.

Behind the variator there are 2x3 small washers that look new, and I've bought a 20mm disc that can be bored up to fit the driveshaft, put just inside the fan.

I'm thinking I'll start with removing the existing washers to see if that helps.

Also, the new belt has gotten a bit more worn in two spots as a result of this, and I'm wondering if I can use it without expecting problems.

Any comments?

[aeroxbud]

If you are taking spacers out. Just be mindful of the crank splines. This explains more. www.pedparts.co.uk/blog/variator-fitting-crankshaft-pulley-spline-damage
If you are adding shims behind the fan. Make sure it's no wonder than the variator boss. Otherwise it will damage the belt. You need to leave enough splines for the castle nut to lock into.
Variator shims are cheap. Much better to buy the correct parts

[morphex]

Jan 25, 2024 15:55:52 GMT -5 aeroxbud said:

If you are taking spacers out. Just be mindful of the crank splines. This explains more. www.pedparts.co.uk/blog/variator-fitting-crankshaft-pulley-spline-damage
If you are adding shims behind the fan. Make sure it's no wonder than the variator boss. Otherwise it will damage the belt. You need to leave enough splines for the castle nut to lock into.
Variator shims are cheap. Much better to buy the correct parts

Yeah I was thinking of ordering shims, but they are expensive to ship and import here, relative to their original price. Like 5-10x.

I'm guessing I just need a mm or two to make this work.

I might have to change half or all the rollers as well, but first I have to make it turn with no or little throttle.

[snaker]

I don't understand a lot of this one.

It appears as if the rig was ok before and now with a new belt, its all screwed up?
If so, sounds like you should be focusing on the wrong new belt rather than modding the CVT to fit?

A couple spots on the belt are now worn?
I don't know this brand, but I assume its a GY6 style CVT?
As in: A actual clutch mounted on the driven pulley vs a snowmobile style with the drive pulley performing a clutch function.
The differences would be that the GY6 style has the belt spinning 100% of the time that the engine is running.
The snowmobile style has the belt just sitting inside the spinning drive pulley and makes or breaks contact during the clutching.
The snowmobile style clutching can cause worn spots or "hour glassing" on the belt on occasion.
The GY6 belt should not do that.

The CVT jamming and choking the engine sounds more like the clutch isn't disengaging.

[morphex]

Jan 26, 2024 12:03:00 GMT -5 snaker said:

I don't understand a lot of this one.

It appears as if the rig was ok before and now with a new belt, its all screwed up?
If so, sounds like you should be focusing on the wrong new belt rather than modding the CVT to fit?

A couple spots on the belt are now worn?
I don't know this brand, but I assume its a GY6 style CVT?
As in: A actual clutch mounted on the driven pulley vs a snowmobile style with the drive pulley performing a clutch function.
The differences would be that the GY6 style has the belt spinning 100% of the time that the engine is running.
The snowmobile style has the belt just sitting inside the spinning drive pulley and makes or breaks contact during the clutching.
The snowmobile style clutching can cause worn spots or "hour glassing" on the belt on occasion.
The GY6 belt should not do that.

The CVT jamming and choking the engine sounds more like the clutch isn't disengaging.

I haven't made changes to the clutch.

The seller of this scooter wasn't honest about the state of the scooter.

He didn't say that it had been rear-ended or something similar either.

What I changed was the belt, nothing else. It ran fine, then started faltering. When it was a bit warm.

After stopping completely, and starting up again, the choking problems started.

I guess you have a point, but I'm leaning towards the belt being too stiff due to low temperature, being new etc.

But how can I check a sticky clutch? Just turn the inner wheel where the belt goes and see if it turns the tire?

[aeroxbud]

If in doubt, fit the old belt again. If it runs right, something is wrong with the belt.
You don't want to be chasing a belt issue of its something else.
A new stiffer belt will affect performance a bit. It shouldn't cause the engine to bog.

[morphex]

Jan 26, 2024 15:38:36 GMT -5 aeroxbud said:

If in doubt, fit the old belt again. If it runs right, something is wrong with the belt.
You don't want to be chasing a belt issue of its something else.
A new stiffer belt will affect performance a bit. It shouldn't cause the engine to bog.

I was standing still in maybe a 10-15% incline for a few seconds on the old belt, just before new years.

It was also slow uphill in general.

I've had 2-3000 kilometres on the bike since I bought it. It's now around 13000 km.

That's why I changed.

I think the new belt was recommended for the V1AAAA, my model, and about 10mm wider than the old worn belt.

The old one also was starting to split on the outer side, like a /, probably in a joint.

This all smells like the previous owner added some mm shims behind the variator, instead of buying a new belt. Or he modded it above the allowed 45 km/h and sold me when it was getting slow.

[geoffh]

So rather than fixacte on the PO let's solve your problem have you tried the old belt?? and if the new belt is 10mm wider then something is way off.

Geoff

[morphex]

Jan 26, 2024 17:13:25 GMT -5 geoffh said:

So rather than fixacte on the PO let's solve your problem have you tried the old belt?? and if the new belt is 10mm wider then something is way off.

Geoff

Have a look at my prior posts, a part of the problem might be that extra air is slipping in after the airbox.