Polini clutch, anyone?

[Cortez]

Everyone is talking only about performance gains, I was wondering more in line with what the thing ACTUALLY does
when installed. I already own it, never tried it though (got it as a spare part with my scooter). I can see the revs at
which it engages can be set somewhere from 4800 and up, but 4800 or so being the lowest.

Does that mean that when the scooter is decelerating and the revs drop below 4800 revs (which is more or less 50mphish)
that the clutch will engage and the scooter would coast at idle revs or am I missing something?

Also, does that mean that the scooter wouldn't accelerate AT ALL from a dead stop at revs under 4800?
If so, yeah, I'm gonna pass.

The stock clutch starts doing it's thing around 2500 revs.

Thanks!

[MJR]

My guess would be the RPM the clutch is fully engaged at wide open throttle off the line but the clutch will engage sooner just as the stock one. On my MyRoad 700i at wide open throttle off the line the stock clutch will allow around 5,000 RPM but it starts to engage around 2,500-3,000 RPM and can fully engage sooner at moderate throttle. Decelerating is a different story when it's engaged to the rear wheel the rear wheel has to drop below a certain speed for it to disengage which on the MyRoad I think is around 15 MPH when I feel it let go. Remember in the CVT the input (engine side) starts out at higher RPM to the output (clutch/rear wheel) and as speed at the rear wheel increases the ratio changes reducing engine speed vs. rear wheel speed.

[Cortez]

Thanks MJR, that makes more sense then what I thought it might do.
Considering I have it already, I might as well try and use it.

[MJR]

I've seen other brands (Malossi, Dr. Pulley) provide a few different colored spring sets so an owner can change how they engage also but I'm not sure with Polini. I know Malossi even offers spring tuning sets for some stock clutches. I've considered a Dr. Pulley HiT clutch for the MyRoad but I think I will start with sliders first.

[Cortez]

I've seen other brands (Malossi, Dr. Pulley) provide a few different colored spring sets so an owner can change how they engage also but I'm not sure with Polini. I know Malossi even offers spring tuning sets for some stock clutches. I've considered a Dr. Pulley HiT clutch for the MyRoad but I think I will start with sliders first.

This thing is adjustable out of the box between 4800 and somewhere over 6000 I believe.
We'll see.

I've had sliders in all my scooters and even with malossi cvt I've used the sliders - 10/10 experience every time.

[MJR]

I was just looking at that here.

http://catalog.polini.com/dep/PI377.pdf

How much lighter have you gone than stock? I'm thinking of going from 28.5 gram rollers to 26 gram sliders.

[Cortez]

I was just looking at that here.

http://catalog.polini.com/dep/PI377.pdf

How much lighter have you gone than stock? I'm thinking of going from 28.5 gram rollers to 26 gram sliders.

Always 10% as per their recommendation.
Did wonders for my DT300 (11 to 9 seconds from 0 to 60).
Still haven't used them in the XC500, but I will.

XC500s CVT is better setup then most I've tried stock, and at WOT it already gets above the max torque value
revs so I'm not expecting a big jump here, but the lower revs at higher speeds will be nice too.

I'm on 33g stock, will be going to 31g and not even looking back if it's not perfect, I'm done with tinkering.
I don't need "as fast as it gets", I'd rather have a small bump in performance and keep lower revs.

I came from a 100hp bike to this, it's never going to come even close so.. I'll just enjoy a smooth ride
(hence the worrying about the clutch being too aggressive of a mod).

[MJR]

How much lighter have you gone than stock? I'm thinking of going from 28.5 gram rollers to 26 gram sliders.

My bad that is the weight on my Aprilia Atlantic 500. I haven't taken the MyRoad apart to see but they may be like the BMW that Kymco makes the engine for at 33 gram stock rollers. The BMW guys seem to like the 28-29 gram sliders. Either of these bikes would be the first time going with sliders. They aren't used in the Burgman 650's electrically controlled CVT which you can change the way it operates with the handle bar mounted switches (Power/Manual modes).

[Cortez]

The only piaggio master 500 scooter that I tried with Dr Pulleys was a friends Gilera Nexus
with the 8 roller setup (there's a 6 roller setup too). He was happy with the gain in acceleration
and smoothness off the line and at low speeds with -10% from stock, but he lost over 10mph from
his top speed and said he should have gone a bit lighter still.

The Pulleys ended up engaging the "overdrive" if you will a bit too soon so the bike couldn't rev out
to it's previous top speed.

Anyways, every CVT is different so it's a bit of a hit and miss.

I'd like to try the JCosta CVT but I can hardly even justify spending money on Dr Pulley sliders
at this point since the stock CVT setup is like I've said rather pleasant to use.

[MJR]

The only piaggio master 500 scooter that I tried with Dr Pulleys was a friends Gilera Nexus
with the 8 roller setup (there's a 6 roller setup too). He was happy with the gain in acceleration
and smoothness off the line and at low speeds with -10% from stock, but he lost over 10mph from
his top speed and said he should have gone a bit lighter still.

The Atlantic has the 25x22 6 roller setup. From takeoff there is a bit of chatter and roughness on the center stand which I would really like to get rid of. All users said the sliders fix that. I was also having a thud feeling decelerating which has been reduced after cleaning the rollers. I plan on checking the stock belt wear it rides on the pulleys with the so called Eddington test where you used a marker on the pulley surface, ride the bike, and see where the belt rides.

[Cortez]

The Atlantic has the 25x22 6 roller setup. From takeoff there is a bit of chatter and roughness on the center stand which I would really like to get rid of. All users said the sliders fix that. I was also having a thud feeling decelerating which has been reduced after cleaning the rollers. I plan on checking the stock belt wear it rides on the pulleys with the so called Eddington test where you used a marker on the pulley surface, ride the bike, and see where the belt rides.

Yeah, that'll go away, it did on the Nexus too.

[RURC]

Always 10% as per their recommendation.
Did wonders for my DT300 (11 to 9 seconds from 0 to 60).
Still haven't used them in the XC500, but I will.

XC500s CVT is better setup then most I've tried stock, and at WOT it already gets above the max torque value
revs so I'm not expecting a big jump here, but the lower revs at higher speeds will be nice too.

I'm on 33g stock, will be going to 31g and not even looking back if it's not perfect, I'm done with tinkering.
I don't need "as fast as it gets", I'd rather have a small bump in performance and keep lower revs.

I came from a 100hp bike to this, it's never going to come even close so.. I'll just enjoy a smooth ride
(hence the worrying about the clutch being too aggressive of a mod).

Cortez,
I have a XC500 (older carb version) and I am getting ready to replace the belt. I was wondering if I should be looking at replacing the rollers / sliders also at this time. Mine is OEM stock and except for cleaning by the shop during maintenance it has never been apart. The OEM belt has lasted very well for me but is it the best one to get? That goes for the clutch and rollers / sliders also.

My riding is mostly to and from work but I do a weekend ride of a couple hundred miles almost every weekend. This is on the highway so I need to be 70MPH at those times. I dont want to mess up the reliability of this scooter but I just want to do the next best thing.

Any help you can give me will be very appreciated.

[Cortez]

Cortez,
I have a XC500 (older carb version) and I am getting ready to replace the belt. I was wondering if I should be looking at replacing the rollers / sliders also at this time. Mine is OEM stock and except for cleaning by the shop during maintenance it has never been apart. The OEM belt has lasted very well for me but is it the best one to get? That goes for the clutch and rollers / sliders also.

My riding is mostly to and from work but I do a weekend ride of a couple hundred miles almost every weekend. This is on the highway so I need to be 70MPH at those times. I dont want to mess up the reliability of this scooter but I just want to do the next best thing.

Any help you can give me will be very appreciated.

Both belt and rollers as per service manual should be replaced after inspection if there's wear.
It's very likely that your rollers have flat spots and I'd replace them (with Dr Pulley sliders of course but, you'd get lower revs at those 70mph you tend to do).
OEM belts by Kymco are amazing re: quality and longevity, I'd stick with them (and I always have).

Look into 30-31g Dr Pulley sliders which will give you a better acceleration and lower revs at higher cruising speeds (haven't gotten them yet myself,
but I've had them in all other scoots I owned before). It transformed my DT300i which had a crappy stock CVT setup (the XC500s setup is IMHO pretty good).

[RURC]

Both belt and rollers as per service manual should be replaced after inspection if there's wear.
It's very likely that your rollers have flat spots and I'd replace them (with Dr Pulley sliders of course but, you'd get lower revs at those 70mph you tend to do).
OEM belts by Kymco are amazing re: quality and longevity, I'd stick with them (and I always have).

Look into 30-31g Dr Pulley sliders which will give you a better acceleration and lower revs at higher cruising speeds (haven't gotten them yet myself,
but I've had them in all other scoots I owned before). It transformed my DT300i which had a crappy stock CVT setup (the XC500s setup is IMHO pretty good).

Thank you for your advice. I just rolled 22500 miles on the original stuff. Are their any really good videos or instruction guides on doing this job? I am very mechanically inclined but I have never touched a CVT like these have.

[Cortez]

Thank you for your advice. I just rolled 22500 miles on the original stuff. Are their any really good videos or instruction guides on doing this job? I am very mechanically inclined but I have never touched a CVT like these have.

There's thousands of videos on the subject on youtube, you can use virtually any scooter video as a reference, they're all
mostly the same or very close. I never looked for XC specific videos, I've only owned it for a month or so. You need a special
tool for the CVT tho.

It's an hour of work at the local shop, I wouldn't bother myself (and never have).

p.s. That's impressive mileage (also pushing it a bit far IMHO).
Good luck.