Please help!! 4 stroke centrifugal clutch

[Kwcustom35]

Is you crankshaft 5/8" diameter?
If soo, then you need a 5/8" to 3/4" shaft adapter like this. View attachment 215313
Thanks.

I got that I'm wondering about how you did the the jack shaft

 

[michael whiteman]

You don't need a jackshaft with a CVT (torq converter). The chain goes from the output to the wheel. Use this speed chart to determine the sprocket size and speed you are looking for. In the box labeled Motor Sprocket put the number of teeth on the CVT. (like 10to15) In the Jackshaft Input and Output box just put 1 and 1. Try different motor speeds and wheel sprockets to determine your top speed.

Motor and Gear Ratio Guide and Calculator for Vehicles with a Jackshaft - ElectricScooterParts.com

Electric scooter with jackshaft motor and gear ratio guide with gear ratio calculator.

electricscooterparts.com

 

[Sidewinder Jerry]

You don't need a jackshaft with a CVT (torq converter). The chain goes from the output to the wheel. Use this speed chart to determine the sprocket size and speed you are looking for. In the box labeled Motor Sprocket put the number of teeth on the CVT. (like 10to15) In the Jackshaft Input and Output box just put 1 and 1. Try different motor speeds and wheel sprockets to determine your top speed.

Motor and Gear Ratio Guide and Calculator for Vehicles with a Jackshaft - ElectricScooterParts.com

Electric scooter with jackshaft motor and gear ratio guide with gear ratio calculator.

electricscooterparts.com

Sometimes jackshafts are used with CVT's as an additional reduction point. This then keeps you from having to run a very large sprocket in the rear.

 

[michael whiteman]

I suppose Jerry, but a guy could go broke creating a drive train this complicated.

Robe, if you do want to add a jackshaft put your torq converter (CVT) tooth count in the Motor Sprocket box.

 

[Nirve]

So I need some detailed instructions for this I have the torque converter brave x 30 series and need to modify it did you just use a step drill as your recessed size? What did you do for a jackshaft I have hand tools should I have these machined

Hey, I should probably split this tutorial off into a new thread and I will when I get to it. Here is how to modify any Amazon CVT for use on a motorized bicycle with 5/8 engine shaft.

First, take a look at the pictures in my previous post

Tools used:

-Step bit https://www.amazon.com/dp/B089T8HJHF?ref=ppx_pop_mob_ap_share

-good hack saw
-big flat file, set of small files
-calipers
-hammer
-impact drill
-dremel
-15/16 nut
-drill press
-snap ring pliers

Parts used:

•35mm OD 5/8 ID bearing https://www.amazon.com/dp/B0824VQSG7?ref=ppx_pop_mob_ap_share

•415 sprocket for 5/8 jackshaft https://www.ebay.com/itm/1654968354...xfcm0ctqmi&var=&widget_ver=artemis&media=COPY

•5/8 jackshaft with threaded end https://www.gopowersports.com/5-8-threaded-jackshaft/ (If you get the longest option it’s enough for two new jackshafts for future build)

•new external snap ring https://a.co/d/5ZjCH9g

5/8 to 3/4 step up shaft adapter
https://www.amazon.com/dp/B07JJ76TH6?ref=ppx_pop_mob_ap_share

Basic how to:

•take out old jackshaft and bearings

•drill down the sleeve on the mount plate, about 36mm from top edge (use calipers depth gauge)(drill clean, slow, straight. It takes time)

•cut off excess material of sleeve at 25mm(1”) from top

•sleeve should be now 11mm to inner shoulder where the bearing sits on

•install both new bearings (hammer, only on outer race)

•determine length of new jackshaft, cut to length ( at least sticking out 1” on the new side)

•mark jackshaft at bearing on the new cut side

•cut a groove in the jackshaft (ideally with lathe but I used hacksaw with spinning jackshaft in mount plate+vise)

•install external snap ring in groove

•install new sprocket on sticking out jackshaft on the new side ( can go either way for chain alignment)

•assemble jackshaft driven side normally

•don’t tighten too much, stressing the snap ring on the other end. The nylon nut will hold itself

The last thing to do is modifying the engine shaft portion. This may be optional but I recommend doing it. The reason is that the CVT pulley’s built in key will almost have no contact with the engine shaft because of the step up adapter.

-Cut a new 3/4 long slot with an angle grinder on the opposite side of the original keyway the shaft adapter (see picture in above linked post)

-file down a new key so it sits in the engine shaft and the step up adapter, but no higher. This key goes in the previously new cut slot in the adapter.

- file down the pulley’s built in key a smudge so it fits on the keyway of the step up adapter (the engines keyway is now on the opposite side)

-you have to file down about a half inch length of the built in key (on the engine side of it)

This should be it. Sorry for the clusterf*** tutorial.
I’m doing this from my phone, I’m out of town. I will post a nice tutorial in a new thread in the future.

Let me know if you have any questions or suggestions

 

[Kwcustom35]

Hey, I should probably split this tutorial off into a new thread and I will when I get to it. Here is how to modify any Amazon CVT for use on a motorized bicycle with 5/8 engine shaft.

First, take a look at the pictures in my previous post

Tools used:

-Step bit https://www.amazon.com/dp/B089T8HJHF?ref=ppx_pop_mob_ap_share

-good hack saw
-big flat file, set of small files
-calipers
-hammer
-impact drill
-dremel
-15/16 nut
-drill press
-snap ring pliers

Parts used:

•35mm OD 5/8 ID bearing https://www.amazon.com/dp/B0824VQSG7?ref=ppx_pop_mob_ap_share

•415 sprocket for 5/8 jackshaft https://www.ebay.com/itm/1654968354...xfcm0ctqmi&var=&widget_ver=artemis&media=COPY

•5/8 jackshaft with threaded end https://www.gopowersports.com/5-8-threaded-jackshaft/ (If you get the longest option it’s enough for two new jackshafts for future build)

•new external snap ring https://a.co/d/5ZjCH9g

5/8 to 3/4 step up shaft adapter
https://www.amazon.com/dp/B07JJ76TH6?ref=ppx_pop_mob_ap_share

Basic how to:

•take out old jackshaft and bearings

•drill down the sleeve on the mount plate, about 36mm from top edge (use calipers depth gauge)(drill clean, slow, straight. It takes time)

•cut off excess material of sleeve at 25mm(1”) from top

•sleeve should be now 11mm to inner shoulder where the bearing sits on

•install both new bearings (hammer, only on outer race)

•determine length of new jackshaft, cut to length ( at least sticking out 1” on the new side)

•mark jackshaft at bearing on the new cut side

•cut a groove in the jackshaft (ideally with lathe but I used hacksaw with spinning jackshaft in mount plate+vise)

•install external snap ring in groove

•install new sprocket on sticking out jackshaft on the new side ( can go either way for chain alignment)

•assemble jackshaft driven side normally

•don’t tighten too much, stressing the snap ring on the other end. The nylon nut will hold itself

The last thing to do is modifying the engine shaft portion. This may be optional but I recommend doing it. The reason is that the CVT pulley’s built in key will almost have no contact with the engine shaft because of the step up adapter.

-Cut a new 3/4 long slot with an angle grinder on the opposite side of the original keyway the shaft adapter (see picture in above linked post)

-file down a new key so it sits in the engine shaft and the step up adapter, but no higher. This key goes in the previously new cut slot in the adapter.

- file down the pulley’s built in key a smudge so it fits on the keyway of the step up adapter (the engines keyway is now on the opposite side)

-you have to file down about a half inch length of the built in key (on the engine side of it)
View attachment 215325


This should be it. Sorry for the clusterf*** tutorial.
I’m doing this from my phone, I’m out of town. I will post a nice tutorial in a new thread in the future.

Let me know if you have any questions or suggestions

Thank you so much brother. Didn't want to do anything until I was sure.. that's pretty detailed I appreciate it.