Q-Matic drive for 79 or 99 CC HF motor

Quenton Guenther

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Hi fellow motorbikers,


Just a few quick comments about the latest drive system for the HF 79 and 99 CC motors.

We currently offer the Q-Matic drive as a bolt on option for the smaller HF 4-stroke motors. The drive has different primary ratios to work with the low RPM, high torque motors, and places the cruising speed near the motor's peak torque curve.

The drive simply "bolts on" and has a primary ratio of 2.06 X 1 and when used with a 56 tooth rear sprocket produces a final ratio of 11.55 X 1. The 11.55 X 1 ratio allows great take-off speeds, good hill climbing, and execelent crusing speeds. In fact at 3600 RPMs [rated maximum RPM level] a 26" bike will cruise at 24 MPH with the stock ratios.

Like all of our production drives the custom 4" Max Torque clutch is located in the rear, and suspended between two large bearings. This design has many advantages, including a slim profile, slower clutch rotation speed, and maximum power transfer. We found during initial design, spinning the clutch at 1/2 speed or under uses a lot less of the motor's power in the process. When working with small HP motors, we need every bit of power we can salvage.

Of course we try to use American labor and parts in the drive whenever possible. We also do our best to use as many "off the shelf" parts as possible to both keep cost down and make it much easier to obtain replacement parts [if ever needed] in everyone's local area.

Have fun,
 
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sorry i know your trying to help but i have to disagree with you, ive seen them as low as $80 with a coupon, and the shipping would pay for a tank o gas to go pick one up in reno, nv, id probably save around $50 bux, thats roughly 1/3 of the total price... neways... maybe i will go drive up there for my next build! quenton, are these gonna be about the same as a q-matic?
 
Hi familyguy,

I don't know if you can find any of the 79 CC HF motors, however they were CARB approved. The 99 CC HF motor isn't CARB approved. Both motors use the same bolt pattern for mounting the Q-Matic drive, however the 99 CC uses 5/16 X 24 bolts. The primary pulley must be larger on the HF motors because they are "low RPM" motors and idle at about 1/2 the speed of the HS 142 or Honda GXH50. And they also "redline" at approx. half the RPM level, creating the need for different primary ratios. Because of the much higher torque of the HF motors, the ratio is also altered to produce a good cruising speed without "over-winding" the motor.

We are currently offering a special version of the drive for the same price as the standard production unit however it doesn't include the front primary pulley as many are using the adjustable pulleyfrom Gringer. The adjustable pulley is part number #1X448 [approx. $13.00]. The Q-Matic must be ordered with the larger AX26 belt to allow for adjustment past 2.5". The AX26 belt is slightly less costly than the AX25 used with the fixed 2.5" drive pulley, as it is a more common size [used on vintage Whizzers].

So to add the the confusion,

Q-Matic drive with 2.5" primary pulley and the AX25 belt is $10.00 more than the standard drive.

Q-Matic drive with AX26 belt and no primary pulley is the same price as the stock production drive.

All drives for motors other than the HS 142 and Honda GHX50, must be special ordered, as they aren't kept in stock. I normally build all the special drives, as we are so busy, we can't remove anyone off normal assembly.

The average additional time is approx. 1 to 2 days extra when ordering the drive for the HF motors.

Please note the crankshaft is slightly larger on the 99 CC motor compaired to 79 CC version, and presents two options. One is to increase the I.D. of the primary pulley to fit and the other is to use #220 sand paper on the crankshaft when the motor is running.

Have fun,
 
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