22 gram Dr Pulley Sliders - performance figures

Having had the sliders in for a while now, I thought I'd summarised my findings and collate all my measurements into one thread. It took me a while to located my original posts hidden amongst other threads.

Ok, results of the speed trials are in, this time based on two-way averages conducted due up-wind and due down-wind, since it was a very windy day today. To give you an idea how windy, the 0-90mph time was 13.95 seconds downwind, but 21.2 seconds up wind! Shocked Note: the original times were only one-way, but I would add that it was a calm evening and there was little if any wind. Another point to note is that my original 0-50/60/70/80 speed rolls were done from a 'drag' start where I bought the rpms up to about 3,000 before releasing the brakes. The 22g slider run was done in a hurry due to traffic approaching, and I didn't have time to faff trying to bring the revs up etc.

Test type:----- Stock 28g rollers: -------- 22g Dr Pulleys:

40-80mph----------------8.60s--------------------8.77s

00-50mph----------------5.15s--------------------4.93s
....-60mph--------------6.93s--------------------6.78s
....-70mph--------------9.44s--------------------9.03s
....-80mph--------------12.22s-------------------12.13s
....-90mph--------------15.79s-------------------17.57s

Speed & rpm figures for cruising:

Speed:----------Stock----------22g Dr Pulleys
40mph------------------------------3,800
50mph------------------------------4,300
60mph------------------------------4,700
70mph------------------------------5,200
80mph------------------------------5,800
90mph------------------------------6,500

DOES ANY ONE HAVE A FULL SET OF STOCK VALUES? If you pass them on, I'd like to edit them into the chart, thanks.


Summary:
With hindsight I should have liked to have done some more testing for lower speed acceleration (0-30 and 0-40 for example) as here the bike really does seem to jump forwards. At lower speeds the 22g slider do give a slight improvements (approximately 5m lead at 50-60mph speeds) over the stock rollers, even with the original figures having been taking from a 'drag' start. At higher speeds the acceleration times are actually slightly worse. This is particularly noticeable with the important 40-80mph roll on which is a good simulation of a typical overtaking manoeuvre. This may be partly due to the climatic conditions today playing with the figures despite me doing a two-way average.

I suspect though it's more to do with the way that the rollers are designed to function. Maximum initial acceleration but with reduced cruising rpms. That changeover seems to happen around 70mph, which for me is ideal. they do seem a fair bit more eager at sub-60mph speeds, and the reduction in cruise rpms should be good at higher speeds. I'm surprised how 'practical' the transformation is considering these are such light 22g sliders compared to stock 28g rollers. Going to 22g rollers would have been much more compromising in the real world I feel. Overall, I'm very pleased.

Good info. Those 22g sliders seem to give the better of both situations: Initial acceleration and tall gear high speeds for economy and reduced engine wear at highway cruising.

yeah, but I've got a dip in revs as you accelerate hard through 5,000rpm and about 50mph. The revs drop a little and you loose urgency for a few moments. Stands out when the bike normally accelerates like a cat with a rocket up its arse.

I have a set of 25g sliders as recommended by the Dr Pulley web site. There is some improvement in acceleration and cruising rpm's and I'm happy with my purchase.

Asking for a set of stock values is of no real use as there are still factors that will affect things. For example, the rider's weight, the windscreen in use, and even such things as a top box and altitude from sea level.

Are your speeds from the Honda speedometer? They will be over-reading probably.

All in all, only a "before and after" of the one machine and rider is a reasonable indication of any gains.

Very good info.

I ride with a GPS and speedo is very accurate 1 mph faster than GPS speed. I'd say speedo is almost true speed.

26 G sliders working for me. Rocket ---NO but fast enough to be fun.

gavinfdavies wrote:

yeah, but I've got a dip in revs as you accelerate hard through 5,000rpm and about 50mph. The revs drop a little and you loose urgency for a few moments. Stands out when the bike normally accelerates like a cat with a rocket up its arse.

Gavin,
Is your Swing running lean on acceleration like mine did with K&N air filter?

I don't think so. The bike still did this between the 22g sliders and fitting the new exhaust. It feels more like the transmission is shift into high gear!

For example, with wide open throttle she accelerates at about 5,500-6000 rpm, but then around 50mph the revs drop to about 4,500 before rising again but now linearly with speed and this continues to full speed. During the rev drop the bike does still keep accelerating, but no as well due to the drop out of the power band as it were.

You can see the big dip in power on my dyno chart I had made before I fitted the exhaust.

I wonder if it's to do with the shape of the sliders? They're marketed as having two different ratios due to the funny shape - one for high acceleration, one for low-rev cruising. I wonder if this is the transition? I might buy a set of cheap round 22g rollers and see if the problem disappears.

Will wait until I've finished the engine work though.

There are 2 different things happening at the same time. Front pulley is contracting making it larger, rear pulley is spreading apart belt is riding lower. That's most likely why RPMs dip. at 50mph.

Generally, placing lighter roller weights/sliders will give you a better acceleration at the starting line but at the cost of some top end speed. Alternately, heavier weights give you better top end speed at the cost of decreased start line acceleration. In either case, you should observe a change in fuel economy, better or worse. I tune my variators with lighter AND heavier weights, equally spaced, and get a little bit better acceleration and increased top end speed and not too much change in he fuel economy.

lcgraham wrote:

< Snip > I tune my variators with lighter AND heavier weights, equally spaced, and get a little bit better acceleration and increased top end speed and not too much change in he fuel economy.

 So what weights are you using on your Silverwing? Rollers, sliders, or both?

Tim

I use both. I try to lose a few grams for the lighter side and add the same amount to the heavy side. I use round roller weights on the light side and sliders for the heavy side. Dr. Pulleys on both

Surely if you have half the sliders/rollers say 26g and the other half 30g then the average is 28g the same as stock so it won't make any difference to performance.

JB

If you search, this topic has been covered many times in the past... DR sliders are more expensive than rollers but supposedly last longer. I am running them but not sure I would again. More than twice as expensive and not a huge difference in performance. Guys, these are scooters NOT Hayabusas. LOL If speed is the thing perhaps a different ride is in order.

Yeah, but there really isn't a faster silverwing class scooter out there. The BMW 650 lacks weather protection, and the servicing cost is ridiculous. The Tmax is too slow and lacks luggage space. The Burgerman 650 is way to fat. The Aprilia & Gilera 850s are too heavy, too rare, and lack luggage space. The Xmax 300 is nice and light, good luggage space and weather protection, but is too slow. Any else that's faster is most likely a bike, not a scooter.

To be fair, a nice little turbo conversion mounted on the end of the head pipe near the air box (how convenient) with a Power Commander 5 would be ideal. Just modest boost. Honest. But I've no turbo experience, so not something I could develop myself.

A nice little turbo would be nice but, as the drive is basically a rubber band and a bit of friction, I can see it all ending in tears.

Should be fine. Plenty of higher-power CVTs out there. CanAm Maverick for one (170hp?)