Thanks for the suggestions/tips guys.
I finally got a few hours in the garage yesterday and I have plenty to report.
I replaced the 1000rpm contra spring with a 1500rpm spring and installed the 5.3g rollers in the variator. Before test driving the A50 I marked the variator face with a black marker (sorry I for got the mark the clutch pates). Took it for a test drive and as I suspected she quickly shot up to approx. 25kph and stayed there. When I removed the variator I can see that the drive belt stopped approx a cm from the end of the variator.
So from here I installed the 8g rollers and took it out again. This time she went up to it's new top speed of approx. 70kph. With the variator removed again, I can clearly see that the drive belt has moved further out to the end of the variator face with approx 1mm of marker remaining.
Changing to 8.5g roller and out again, this time about the same as with the 8.0g weights with the top speed being approx the same. With the variator removed I can barely see any ink left on the variator face edge.
I even changed the rollers to 9.0g weights and test drove that, this was where performance fell off, throttle response and pick up was sluggish..... I put the weights back in the case and gave up on them direct.
The above tests were with the 1500rpm contra spring, so I conducted it all again with the 1000rpm contra spring and the original spring. For me the 1000rpm contra spring felt the best but I do question the originality of the "original" contra spring. It's a black spring with blue paint down one side. The Naraku contra springs that I have, the 1000rpm spring is blue and the 1500rpm spring is yellow. So I'm wondering if the original contra spring was replaced at any time to a slightly stiffer one or is that the original colors for them?
I did check the drive belt and it's an Kymco original that has plenty of wear on it which measured 17mm across the top. Before work tonight the new Naraku drive belt came in the post, so she'll be installed tomorrow.
What really makes me scratch my head in disbelief is that I have to go to heavier weights to get any solid performance where others here on this forum go with lighter weights.
I've not owned the A50 for a month yet and have no idea what the previous owner has done but I'm working in the direction that I want.
I also changed the main jet to an 88 yesterday but I must admit I've not really noticed a huge difference from the 82 that I installed 2 weeks ago. And even that, the 82 didn't really make any seat of your pants difference either from the 80 that it replaced. The old chinese scooter I had, I used a 92 main jet in that and that really worked well. So I'm up in the air if I should go a bit larger with the jet or go down smaller?
In the mean time, lets see what difference the new drive belt will make.
Tuko