KidNMe Performance

Why upgrade your Variator?

Your Variator, (or, Front Pulley/courier) is attached to your crank shaft and is the first part from your engine to your transmission. It is a great way to start your performance mods and get a little boost in your take off speed and a little more "oomph" in your hill climbing. It's relativly cheap and easy to install!
First, here are the Parts that make up your variator.

Performance variators offer a steeper ramp angle and maybe a steeper angle on the slide faces than a stock one. Why is this important?
If you've watched the "How your CVT works" video, you've seen that roller weights, roll outward with centrifugal force (More rpm's) and push on the backing plate.
 
 The longer you can keep those rollers from pushing the backing plate out (Closing the variator), the longer your belt stays in the  lower part of variator, (Fully open) increasing your take off speed/torque.  
 
As you gain speed (more rpm's), the rollers combined weight, pushes on the backing plate, forcing the back half towards the front, squeezing the drive belt towards the the outer diameter of the slide face and into your top speed range. (Fully Closed)

Lighter weights improve your take off and
Heavier weights improve your  top speed but it's a trade off of, one or the other.
Go TOO LOW and your engine will be screaming and only going 20mph (You may be able to pull off a few doughnuts though!).
Go TOO HIGH and your top speed will increase (to a point) but, your take off speed will be dramatically reduced.

When considering this mod, your first step is to find out what SIZE and WEIGHT "Stock" rollers you have in there now and what you want to accomplish with the change.
If you don't have a gram scale handy, in a pinch, you can take one roller down to your local post office and have them weigh it for you. Now, you'll have a starting point!

 

"BOB's Changing his Rollers"

We'll take the hypothetical "Bob" here and his stock 150cc buggy and make an example.
Bob pulled his stock weights, weighed them and found he had 15 gram rollers in there.
He knows that if he wants to take off from the line faster, He'll lower his stock weights a few grams.
If he's looking for a little more top end?, he needs to go up a couple grams.

Bob's buggy is slow at takeoff and he wants a bit quicker response and better hill climbing ability so,
after reading all the information on the Internet, he drops down 6 grams and buys a set of
9g roller weights.

When he first installed them, he liked the extra pull at take off but he thinks the engine revs up too high before it starts moving for his tastes plus, he lost a little over 5mph on his top end!
Looks like Bob dropped down a little too far for his liking:-)

After trying a little "mixing and matching" with his new and old roller weights, he then bought and installed a set of 12 gram slider weights and now Bob has some of his top speed back and still has a much better take off than when it was stock!

A Happy medium and...

You will only gain just so much top end by going up in weight from stock.
Results will vary of course but generally speaking, you're looking at only 2-3mph top gain at best.

 

When Bob realized he bought too light a roller weight, he kept 3 of his stock 15 gram rollers in there and alternated 3 of his new 9 grams rollers and got an average of 12 grams   ! Brilliant!

 
Most Chinese clone 150cc motors take the 18X14 mm size roller weights (18wX14h-Always in metrics :-) )
For the CN & CF 250 motors, most take the 23X18 size roller weights but don't take my word for it, you'll need to check it to be sure. There are hundreds of models out there!

The actual "stock weight" of your rollers will vary from machine to machine, mfg year, etc.

LOW END TORQUE/VRS TOP END

Each gram you drop gains low end torque and better hill climbing at the sacrifice of a little top end.
10-14 grams is very popular in most 150cc applications and can be found in
4-15grams readily.
17-21 grams are very popular for most 250cc applications and can be found in
14 - 25grams readily

As a rule of thumb with all vehicles, Top speed could drop almost 3/4mph for each gram you go lower, after your initial, 1-1/2 - 2 gram drop.
It's not as dramatic an increase when you go higher in weight.
So, you may need to play with different weights to get yours setup the way you like it.

Rollers vrs Sliders

 Your transmission comes stock with Roller weights.
A "Slider" weight doesn't roll up the variator ramps but it "Flips" up the ramps because of its flat sides. This holds the weight at the center of your variator for a couple seconds longer for a little better takeoff speed. This is similar to dropping a couple grams in roller weight.
EX: Exchanging your stock 15gram Rollers for 15gram sliders, will keep the same top end and give you a little boost in low end.

There are many opinions out there as to which is better, rollers or sliders. On one hand, you get to carry a gram or two more weight for your top end and still get the boost on low end with a slider but on the other hand, a slider only makes serious contact on one side all the time as opposed to a roller and are more expensive.
At KidNme, we are on both sides of the fence so, we we think that "dialing it in" with the cheaper roller weights like "Bob" did then, get the slider weights at the avg weight you ended up liking is the best method.

 After contemplating why we were trading off speed for torque all the time and learning something from Bob's little trick,
the "KidNme" sat in the garage and went over the whole "Variator process"
After trying all the top brand variators on the market and
finding nothing really "special" in any of them,
We started playing with our own stock 150cc variator to try to change the whole:
Hi/Lo Trade Off" Issue!

We figured, with 2 different weight rollers, we could manipulate the time (or force) it takes for each weight to travel up the ramp! It takes a certain amount of force to push the backing plate out and now, with 3 of the weights lagging behind in that task, we managed to keep the motor in a higher rev longer but still had the eventual "combined weight" to push the plate out as far as it did before. It worked!
After sharing this information with our factory boys in Taiwan, one of them had the bright idea to angle the ramps differently too!
We then added 3 "Heavy Ramps" and 3 "light Ramps" and got more of what we were looking for!
After designing and testing our first one here at our shop
then getting them into the hands of a few of our Proto-Testers, we knew we had a hit!
Not leaving well enough alone, we decided to add vents in the slide face for cooling and reduce the over all weight!
 
So now, our DR2 Variator is the most "tuneable" on the market!  With the 4 sets of roller weights included (2 sets hi & 2 sets low) and even more weights available, you get several "mix and match" choices for that low end take off and keeping your top speed too!

The DR2 let's you have the best of both worlds!! 
Our Variator kits will not work with a kick starter. There are no teeth on it to engage with the kicker. It will work but you'll have to rely on your electric start.
We are working on a model that will accomodate this in the future.

  Will it fit?
Our DR2 will fit most GY6 150cc *Scooter, Buggy and Atv's.
 the DR2 Uses (6) 20X17 roller weights

                   

Already have our DR2 installed and want to tell us about it?
We'd love to hear from you!