I actually just hit a very lucky 65mph (indicated) today. Video below. I think I might've been in a small draft without knowing it. I had it WOT of course. I think it was a draft/wind because I went from 61 to 65, and back down to 61 without changing throttle.
With the recent new chinese belt I seem to be getting lower RPMs at top end than I used to with the Gates belt. I'm thinking because the chinese one is exactly 20mm wide where the Gates was 19mm brand new.
I currently get: 60mph is 6.8k rpm , 65mph is 7k. This is with the 108mm variator FAN in. 60mph was 6.5k with the 115mm fan I believe.
65mph video: wobbly-ness is video stabilizer, because it was too SHAKEY to read without it. Audio is mostly wind noise, unfortunately my helmet mic wasn't on, but I screamed HOLY COW loud enough to be heard over the wind a little lol.
Just redid a test now that my bike has been stable. The variator fan size DOES affect RPMs! Going from 108mm up to 115mm lowered RPM by 500 all around.
--These results are with Koso 115mm variator + 12g Dr Pulley sliders; everything else on my bike is stock--
What effects that is the curvature on the pulley, like the Prodigy Variator it comes with its own Fan pulley and it is a very good variator for top end speed but gives it up in the low end which means because of the curvature the belt climbs up really quick so you loose some low end pull. Alleyoop
Ohh interesting. I actually have 2 of these 115mm fans, so after reading your post I put the 108mm vs the 115mm face to face and the 115mm does curve in deeper. Not sure about the one that's in the bike now. Both of these 115 fans only have a little "H" printed on them and the 2 holes are smaller than stock variator (had to rig up my own holding tool).
If I figure out if I've lost any acceleration from the lowered RPM I may take it back out, but I do like the lowered cruise RPM. Hmm hmm hmm...
Alleyoop, does this fan curve have any affect on how high the belt gets pushed up at top speed? I have the 12g Dr Pulley sliders in and I've always been afraid they're slightly too light to push the belt up as far as it can, and my usual max speed is 57-58mph. This is relative to the cheap 12g sliders I once had in, which seemed to act slightly heavier and always pulled me right up to 60mph. ** I can see this visually by revving it to speed with the CVT cover off; the 12g Dr Pulley sliders bring the belt mostly up, and when I let off the gas the belt jumps up MORE, close to the edge. With the 12g cheap sliders the belt went up and stayed up at speed and didn't move with deceleration. Just wondering rather than buying a new set of sliders, does this curved fan help give the same effect of heavier sliders for top speed... probably not?
You have two things to consider the curvature and the weights. The weights, depending on the grams will close the variator with less rpms or require more rpms. Same as the clutch pads springs all depends on the centrifugal force applied. The curvature will also control how fast the belt climbs and how high it climbs. If you notice ON most the Curvature near the edge is angled more both pulleys and that is there for a reason so the belt CANNOT fly out of the pulleys. So if you put the belt on and close the variator you will probably see how high it MAY climb BUT depending on the weights and rpms it MAY NOT close that much. Alleyoop
I'm not completely sure I'm understanding it. Here's a quick diagram with how my 2 different variator fan pulleys look from the side (a bit exaggerated). A is the 115mm fan, and B is the 108mm fan. I started with B and changed it to A and my RPM lowered by 500 all around. If I understand, it's not because of the bigger size, but the new curvature, which causes the belt to ride up the pulleys sooner, therefore lower RPM everywhere. BUT, has this also affected how high up the belt rides once you hit top gear? Similar to putting in heavier weights if you previously had too light weights?
Of course look at the angle on A the belt will never get up there the variator will be close much sooner look at the hump in hte middle so now picture the Variators hump hitting that hump then you will see that the belt will only go so high when squeezed. In the pictures put the other half in the VARIATOR and you then will see it more clearly.
Tell me if I have this right or if I'm still not understanding: So going from B to A makes the variator close and hit top gear sooner, but the belt won't ride as high at top gear, therefore LESS top speed?
A. Correct, But you can get more speed by increasing the RPMS, A gives you more low end grunt. B. Belt climbs high but quick less low end grunt.
Now you also have to think about the Curvature on BOTH sides the Variator and the Fan Surface. If they have a matching curvature that is great if one does not make then the belt will take the more curved route and you loose belt height. A good example of matching PULLYS is the PRODIGY PERFORMANCE VARIATOR it comes with a matching Fan plate.
Here it is on my TRIKE it is 115mm and notice the mark it left on the edge of the 115mm THAT BELT is climbing HIGH HIGH HIGH that is 1/4+ inchs higher than the OEM that is a LOT But higher rpms.
Here's how the belt climbed in my 108mm variator (B)
You say A gives more low end grunt, but wouldn't the lowered RPMs give it less grunt? Assuming no changes to the weights between A and B. Is there some other factor into play that I'm missing?
All depends on where the belt is at the time If it is high on the pulley less grunt lower in the pully more grump at lower rpm just like a car first gear lots of grunt low rpms 2nd gear less grunt little higher rpm.
What I do not understand is why all this for a little bit of anything really. It is not worrying about a little difference here and there only if it is a great difference and you do not like the difference. You will never find a setup with a STOCK motor to give you great bottom and top you will have to settle on a mid solution descent bottom and descent top or GO full out low or full out high.
If your scoot can Register 60 or so on its speedo that is great for a stock motor. Realizing that it is not really the real mph I would say 10% on the high side. Alleyoop
Oh I'm mostly just trying to understand how it works. I was trying to figure out if I could avoid buying a heavier set of sliders if changing the fan gave the same effect on top speed. You're right, it's only a small difference, but I enjoyed seeing that 60mph every time I went wide open.
What where you on 95?
..BAD TO THE BONE..
