I have just noticed that the belt on my Kinroad (CN250) sits about 20mm below the top of the driven pulley and possibly not completely at the bottom of the variator pulley.

Perhaps it has always sat there but I never gave it any thought until now as I try and optimise the performance of the buggy!

It is a new Kevlar belt from Glade, and this makes me wonder if the original belt sat in the same position.

Any advice on how to improve this to get maximum efficiency out of the CVT?

Cheers!

my belt does not sit that low, did you pull the driven pulley apart any when you put the belt on?

if the driven pulley is pulled aprt or the main spring does not let it close all the way the belt will sit lower in the pulley and higher in the drive pulley

Yes, Of course. If I don't separate the halves of the driven pulley, I cannot get the belt on the front variator shaft. As you can see I have the blue main spring which I am sure would offer plenty of return force.

whats the numbers on the belt?

22x10.5x830

The original belt is marginally bigger but I don't think it could make that big of a difference.

I don't think it's the length - it's the 10.5 number in the middle there.

That is the normally the angle of the belt x2, meaning you've only got a 5% angle on each side of the belt. it's sitting low on the driven side because it can't get all the way into the variator side. The inner part of the belt is too wide of an angle.

Most CN250 belts have are (give or take) 828x22.5x30 - whereas an 830x20x30 belt will work too. The these belts have a 15° angle on each side which allows them to get all the way down in the groove.

You probably need a different belt.

-Mike

This should be the number on the belt that I shipped.

828/20/30

Glade

Ahh well there's our problem. I have 2 belts with the aforementioned specs Glade.

I did some testing this arvo and determined that the ibelt was not going all the way in to the Varaiator shaft.

At present I am using a combination of Dr.pulley outer and standard inner because of certain other issues. The only difference I note between the surfaces of the 2 is that the angle of the Dr.Pulley set is slightly more meaning that the inner meeting points are higher up the cone. This would hence increase the size of the driving point at its lowest rev speed and hence increase the gear ratio, and reducing the torque capability at low speed. On this note, using a Dr.Pulley variator is actually a step backward.

Anyone disagree?

EDIT: These differences could be because the variator is not the correct one for this buggy. Waiting on confirmation of this.

I know what you r saying BugSta,but what I did I put the 2 halves of the vari together and notice that the belt didn't go all the the way to the top thus losing top speed speed.I machined only the movable side to bring the to halves together move thus putting the belt higher at hi rpm and lower at low rpm.U can not take that much off and only on the movable side hope this helps. Remember I have a 150 dont know if this would work for you.Just an idea!