Villiers Board track racer
- Thread starter Villiers
- Start date
I have a couple of belt drive bikes, one with a CVT front pulley.
In my experience that cheap belt clutch pictured is ok on small engines. On a thumper like that flathead, I would use a Hilliard extreme duty clutch.
The Hilliard clutches are easy to tune. The pulley clutches come with 1800 rpm springs installed, but they make springs for 830, 1200, 2000, 2300 & 3000
Easy to change springs. 4 shoes. A high quality unit.
Now about that CVT idea...
I have the drive pulley from a Comet 20 series torque converter on my sidehack. It does work, but it has it's own quirks.
Engage speed is adjusted by belt length. Going up one size raises engage speed. This sounds good, but it can be a pain in the backside.
The belt is the clutch facing. With a GX120 it will launch the bike without pedaling. The price you pay for this is belt wear. Under extreme conditions I can make a belt smoke.
The automatic tension of the CVT without the spring pulley pulls very hard on the belt. I found out that a cheap belt will stretch if you spin the engine up to 5k or so. The pulley just keeps pushing on the belt. In short, this thing is hard on belts with a 120cc 4 stroke. Kevlar B section belts work great.
.
In my experience that cheap belt clutch pictured is ok on small engines. On a thumper like that flathead, I would use a Hilliard extreme duty clutch.
The Hilliard clutches are easy to tune. The pulley clutches come with 1800 rpm springs installed, but they make springs for 830, 1200, 2000, 2300 & 3000
Easy to change springs. 4 shoes. A high quality unit.
Now about that CVT idea...
I have the drive pulley from a Comet 20 series torque converter on my sidehack. It does work, but it has it's own quirks.
Engage speed is adjusted by belt length. Going up one size raises engage speed. This sounds good, but it can be a pain in the backside.
The belt is the clutch facing. With a GX120 it will launch the bike without pedaling. The price you pay for this is belt wear. Under extreme conditions I can make a belt smoke.
The automatic tension of the CVT without the spring pulley pulls very hard on the belt. I found out that a cheap belt will stretch if you spin the engine up to 5k or so. The pulley just keeps pushing on the belt. In short, this thing is hard on belts with a 120cc 4 stroke. Kevlar B section belts work great.
.
With a 79cc 2.5hp OHV engine, that inexpensive clutch seems to stall when new at about 2400 rpm. Not a problem with that engine, we spin them to 6000 rpm
Your Villiers tops out much earlier, and makes about 30% more torque than the 79cc OHV. I doubt you will spin that old girl more than 3500 very often.
You could use either clutch. The Hilliard could be easily tuned to stall at a lower rpm, giving a wider useful speed range.
If you have ever tried to change the garter spring on a cheap 3 shoe clutch, you know just how much you would like to slap the bell end that designed it...
The gauge line for the pulley is similar for both clutches. If you go the cheap route & want to upgrade you can easily enough. Personally I lean toward doing a job once with high quality parts.
.
Your Villiers tops out much earlier, and makes about 30% more torque than the 79cc OHV. I doubt you will spin that old girl more than 3500 very often.
You could use either clutch. The Hilliard could be easily tuned to stall at a lower rpm, giving a wider useful speed range.
If you have ever tried to change the garter spring on a cheap 3 shoe clutch, you know just how much you would like to slap the bell end that designed it...
The gauge line for the pulley is similar for both clutches. If you go the cheap route & want to upgrade you can easily enough. Personally I lean toward doing a job once with high quality parts.
.
