School Me on Transmissions

cory151

Member
Educate me. So If I wanna run a HF 79-99cc in frame my immediate options seem to be the AGK jackshaft kit and clutch, or the QMATIC or do you need both? Whats the deal with these QMATICs you cant just buy one, it must be bought through a "dealer?"

Any specific info on the above would be great, extra credit for anybody whos used both and can compare.

Later, Cory
 
Educate me. So If I wanna run a HF 79-99cc in frame my immediate options seem to be the AGK jackshaft kit and clutch, or the QMATIC or do you need both? Whats the deal with these QMATICs you cant just buy one, it must be bought through a "dealer?"

Any specific info on the above would be great, extra credit for anybody whos used both and can compare.

Later, Cory

Hey Cory, you can use either tranny. the AGK jackshaft runs the clutch directly off of the driveshaft, whereas the EZM has the clutch attatched to the rear pulley.

Both set-ups run a #41 chain from the final drive cog to the rear wheel mounted sprocket. The AGK uses a #35 chain for primary drive, whereas the EZM use a v-belt.

A good source for comparison is AGK as the run both types....call them or wait for them to chime in perhaps.

scotto-
dnut
 
Last edited:
Hey Cory, you can use either tranny. the AGK jackshaft runs the clutch directly off of the driveshaft, whereas the EZM has the clutch attatched to the rear pulley.

Both set-ups run a #41 chain from the final drive cog to the rear wheel mounted sprocket. The AGK uses a #35 chain for primary drive, whereas the EZM use a v-belt.

A good source for comparison is AGK as the run both types....call them or wait for them to chime in perhaps.

scotto-
dnut
Thanks for the info Scotto. The AGK looks like a pretty simple and straight forward setup.
 
Cory call david in sales at Staton. He told me that he had one for the 2.5 about $200.
 
Chain primarys are high maintenace because of the high speed and small engine sprocket. I would go with the belt primary.

For a different drive for this engine, that turns the cylinder foreward, that has no chains at all, check out my thread in DIY Forum, "In Frame Predator Fricton Drive". I used a slipper belt clutch, sorta complicated, but it would be much easier for most folks to go with a cent clutch instead.

This drive works great, 300 miles with no problems and no obvious tire wear yet. 40 mph at 4500 rpm.

Sorry, this site won't let you re-post pics, and I don't know how to cross link threads yet.
 
Chain primarys are high maintenace because of the high speed and small engine sprocket. I would go with the belt primary.

For a different drive for this engine, that turns the cylinder foreward, that has no chains at all, check out my thread in DIY Forum, "In Frame Predator Fricton Drive". I used a slipper belt clutch, sorta complicated, but it would be much easier for most folks to go with a cent clutch instead.

This drive works great, 300 miles with no problems and no obvious tire wear yet. 40 mph at 4500 rpm.

Sorry, this site won't let you re-post pics, and I don't know how to cross link threads yet.




Yes Ive actually read your thread already (great job) if I was into friction drives Id have already copied your setup.
 
I have used this setup for a couple years with good results. I have put thousands of miles on it and it still works as good as the day I installed it.

Torque Converter Backplate & Jackshaft (400825), www.bmikarts.com : BMI Karts & Supplies : Go Karts Parts : Racing Go Kart Parts : GoKarts : Versailles, Ohio : USA : Indoor Track : Tips

It's about the same as the AGK kit, very heavy duty, usually found on go carts. It comes with a 20t and a 10t on the jackshaft but one could use a different combination. I like a 12 to 1 ratio for that engine.

Tom
 
I have used this setup for a couple years with good results. I have put thousands of miles on it and it still works as good as the day I installed it.

Torque Converter Backplate & Jackshaft (400825), www.bmikarts.com : BMI Karts & Supplies : Go Karts Parts : Racing Go Kart Parts : GoKarts : Versailles, Ohio : USA : Indoor Track : Tips

It's about the same as the AGK kit, very heavy duty, usually found on go carts. It comes with a 20t and a 10t on the jackshaft but one could use a different combination. I like a 12 to 1 ratio for that engine.

Tom



Wow that seems like an extremely economical setup, i like it.
 
The jackshaft kit from BMI doesn't come with pulleys or belt. The 2 that I have received in the past do come with 2 sprockets a 10 tooth and a 20 tooth. A 10 tooth clutch can be used on the engine output shaft, run a chain to the 20 tooth then another from the 10 tooth (on the jackshaft) to the rear wheel. I use the 60 tooth rear sprocket from BGF. These guys have a good selection of sprockets and pulleys:
Surplus Center - Power Trans Gearboxes Gear Reducers Bearings

You could use a pully and belt set up but would likely need a belt tensioner.

Tom
 
The BMI jackshaft kit is definitely a low cost alternative to our jackshaft kit. I'm sure it will work fine in a motorized bicycle application. Ours is CNC machined, uses high grade hardware and is a more complete kit, however, I'm not really sure it's worth more than double the price. Maybe we need to contact BMI and carry their kit as a low cost alternative to our current jackshaft kit. BMI has a lot of interesting products. If you have not been to their website you should check it out. Their prices are competitive and they have some neat stuff.
 
The BMI jackshaft kit is definitely a low cost alternative to our jackshaft kit. I'm sure it will work fine in a motorized bicycle application. Ours is CNC machined, uses high grade hardware and is a more complete kit, however, I'm not really sure it's worth more than double the price. Maybe we need to contact BMI and carry their kit as a low cost alternative to our current jackshaft kit. BMI has a lot of interesting products. If you have not been to their website you should check it out. Their prices are competitive and they have some neat stuff.

Their shipping cost to here in California is the thing that kills the initial cost and they have a minimum cost on orders for shipping. Since you're in Colorado, it may not be as bad. Worth checking into for sure.

dnut
 
Back
Top