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Well, boyz and gurlz,

The old chopper guy discovered yet another "quirk" of our CVT trannies... Lately I've been running a lot of errands on "Minnie Mouse" for meds, etc. down a long stretch of local 8-lane.  It happens to have a nice, 4-mile straight stretch, with a stout 2-3% grade, UPHILL south, and DOWNHILL north.

The uphill stretch gives the scoot a good test of its ability to maintain speed on a grade, and the other direction, downhill gives an opportunity to find out the ABSOLUTE top-end with the variator closed up tight.  (The speed-limit is 65, and typical traffic-speeds along there run 70-80 in the right "slow" lane and 80-+ in the left 3 lanes.)

Uphill, the old mouse will maintain an indicated 72 mph (actual 69).  On the return trip, downhill, I hit an indicated mph (actual ) which probably approximates what would happen (minus a few mph for windshield-drag, etc.) if I had the IDEAL roller/slider setup and everything was "perfect".

For the record, the shop-manual for the Kymco GV 250 lists absolute top-speed at 70 mph.  THAT is for the "Dink" version, and maybe 5 mph slower than a typical American market Grandvista or Bet & Win.  Mine had a one-tooth final gear upping years ago, but all else is stock.

Now, the INTERESTING part!

After reaching the bottom, and on the level, the old mouse only slowed to indicated mph (actual ).  And, she'd stay there even with the throttle backed off a little.

When I came on slower traffic, I had to slow to 65.  But... no amount of throttle-manipulating would get back to again.  So...  The downhill allowed the variator to perform to "perfection" and the engine had the ponies to keep the speed pretty high on the level.  I do believe I got just a "taste" of what a perfect combo of weights and such COULD offer.

Definitely worth some experimentation...  Playing with weights in my old 150 brought major improvements in acceleration and top-speed, and I think the same might be true with the 250.

Now I know my rollers are the originals, with 8 years and 15K miles on them, they surely are well-worn.  I intend to try some 18 or 19-gram Dr. Pulley sliders when time and budget allows.  Right now, health issues with the Missus keeps me from having any free time, and paying for meds takes ALL the money and more, but the prospects are intriguing.

As a side-note, I can see the selling-points of the Vespa-jockeys...  mph on 12" wheels is NO problem if you're running speed-rated tires, and the wheels/tires are well balanced.  Smooth as glass!

Riders who are wondering whether it's worthwhile experimenting with rollers/sliders and weights, rest assured, it is!

Ride safe, work that tranny!

Leo in Texas

PS:  It WAS fun to actually keep up with traffic for once...  Even though a guy in a lettered-up, numbered Porsche played "thread the needle" around me, and surrounding mph traffic doing at LEAST 80 mph FASTER than us... Doing near the "double-century mark" in a cage must be a trip...  LOL!