Ideal RPM target range  By  Deleted (Read 3,556 times)

The fluxuation is normal. Usually happens when the variator is bottomed out.
The engine revs, by the time it reaches 7,5k RPM sliders will move, but the belt only starts pulling up on the variator by the time the engine has already reached 8k RPM.
Since you're running in a low gear there, the acceleration losses would be negligible, compared to running it at a perfect 7,5k constant.
Engine torque after 7,5k RPM goes down, but it's mostly only noticeable when the variator reaches higher gear.

It's hard to get them stay at 7,5k RPM

On some bikes, engine RPM during acceleration also depend on how far you open the throttle.

Definitely!

I just finished 2 months of roller-experimentation on my Xingyue 150. There are a LOT of variables, rider weight, engine mods, etc. Here's what I experienced...

I weigh 235 lb, my engine is stock except for "blue" CDI, Bando coil iridium plug and UNI sock filter. Also, my recent exhaust change to a 2-stroke expansion-chamber type, which raised my engine's "sweet-spot" from its former 7,000+ rpm up to 8,000 rpm.

My variator is a Prodigy, and my clutch is bone-stock. Clutch engagement is perfect, so I never messed with it.

I started experimenting on the Prodigy variator with 13-gram rollers which gave me a top speed of near 60 mph, at a modest 7,000 rpm (not even reaching my engine's sweet-spot). GREAT top end, but VERY poor acceleration, and poor hill-climbing.

I then switched to 12-gram rollers. Just ONE gram less, and they gave me SUPER acceleration, but a miserable top speed of only 45 mph at over 9,000 rpm!

I then mixed 3 ea. 12-gram and 3 ea. 13-gram rollers and THAT setup provided the best overall performance I've had yet. GOOD acceleration and hill-climbing, and a top speed of 51-54 mph at 8,000-8,300 rpm.

That's the setup I have right now, and it does provide the best all-around drivability I've had. I also have a set of 13-gram Dr. Pulley SLIDERS which I believe might be even better, but I have not gotten to installing them, as I am working to trade up to a 250 scooter.

I found roller-weights have THE most dramatic effect on performance of any mod I've tried, so that area certainly deserves much attention.

Though I did not get to trying SLIDERS, from what I've seen, they should be a vast improvement over rollers. The flat sides of the "V" shaped sliders offer the ability to FULLY open and close the variator for best ACCELERATION, and TOP-SPEED.

Rollers only contact the variator at the CENTER of the rollers, losing about 1/8" of potential "push" and "release" of the variator, compared sliders. The difference in operation between rollers and sliders is so visually noticeable that if I were going to continue tweaking my 150, I would probably stick exclusively with sliders.

From my experience, even ONE-gram difference in weights can make TOO large a difference in performance, so be open to mixing weights to get it just right.

I hope this may at least give you a starting-point to work from. In my case, local streets have been RADICALLY re-designed this year, raising common traffic speed to well-over 55 mph. This, combined with recent health issues now require me to travel between Dallas and Fort Worth (about 35 miles one-way) at freeway speeds (and around here, THAT means steady 70 mph+ sustained speeds) has prompted me to start searching for a liquid-cooled 250cc or larger scoot.

Right now, I'm "bird-dogging" a pretty nice well-used, but not worn out Kymco 500cc with fuel-injection. It's STILL a small, nimble scooter in city traffic, but with 15" front, and 14" rear wheels, huge dual-disk front brakes, around 30 hp and very solid frame, will cruise at 80 mph pretty well. It seems to me to be a near-perfect answer to being either a handy scooter, or capable road-bike, whichever is needed at the time. We'll see...

My real FAVORITE generic scooter will probably always be the air-cooled GY6 150. So long as your travel needs remain at 50 mph or less, they are unbeatable. Feather-light, short and nimble, they are the real "work-horse" of scooterdom.

Now that I'm pushing 70 (years, NOT mph... LOL!) I find arthritis makes it nearly impossible for me to get on and off of a motorcycle anymore. A flat-floor, step-through scooter is actually best for me, but I've found I can "live" with the "hump" common on most of the maxi-scoots. I think the trade-off of having a "hump" in the floor is probably worth it to have both a grocery-getter AND highway-cruiser in ONE scooter... We shall see!

Spend plenty of time with those rollers, OR sliders, and you'll eventually get the best all-around performance out of your sharp scooter!

Leo (wishin' y'all the best) in Texas

I have a digital Speedo and its still way off my 57 was 67 on the speedo

The best acceleration for me is at takeoff at WOT my rpms max at 8300. Then as i continue to gain speed the rpms stay between 7500 and 7900. Wish i could cap my max at 8000 but you cant do that much fine tuning i guess.

WIth the stock rollers my takeoff was slower. rpms would max at 7600 and as speed increased they would remain between 6500 and 7000...well below the power band.

Workin on the T3 .

While I was replacing my fuel pump this weekend I did a quick duct tape install of a tachometer that just arrived Saturday. This mornings commute to work was very enlightening. Running downhill at full song I'm spinning over 9 grand and still wishing for more top end speed. That ain't good.

On the flat wide open it's between 8 and 8.5. The chinometer says 50-55 and I know that's lying. Any sort of hill and it grunts down to between 7.5 and 8. I'm guessing that's the power band of the engine.

I predict slider experimentation in my future.