Jackshaft Need help building 3hp Briggs Jack shaft

RocketJ

Member
Joined
Dec 2, 2017
Messages
109
I plan on installing a jack shaft and suicide shifter on my bike. I was offered an old 3hp Briggs motor, which is fantastic, except for the fact that the crank case has no mounting holes, which makes a torque converter unusable for the build. Instead I've decided to go with a home made jackshaft.

Currently my plan is to take 2 bearing housing with mounts and install them on the bottom stem of the bike in the gap between the wheels and back stem. Then I would run a rod and 2 pulleys/gears for the reduction ratio.

Is there any better way of doing this? If not, where can I purchase the reduction pulleys and the rod to install in the jack shaft?

Some photos of the motor and bearings below:


https://imgur.com/a/2g7yi

https://cdn3.volusion.com/nfczr.pzckq/v/vspfiles/photos/Kit7362-2.jpg?1505821334
 


Street Ryderz

Well-Known Member
Joined
Oct 14, 2016
Messages
3,271
I plan on installing a jack shaft and suicide shifter on my bike. I was offered an old 3hp Briggs motor, which is fantastic, except for the fact that the crank case has no mounting holes, which makes a torque converter unusable for the build. Instead I've decided to go with a home made jackshaft.

Currently my plan is to take 2 bearing housing with mounts and install them on the bottom stem of the bike in the gap between the wheels and back stem. Then I would run a rod and 2 pulleys/gears for the reduction ratio.

Is there any better way of doing this? If not, where can I purchase the reduction pulleys and the rod to install in the jack shaft?

Some photos of the motor and bearings below:


https://imgur.com/a/2g7yi

https://cdn3.volusion.com/nfczr.pzckq/v/vspfiles/photos/Kit7362-2.jpg?1505821334
Any part you may need is available at Stanton Inc.
 

Street Ryderz

Well-Known Member
Joined
Oct 14, 2016
Messages
3,271
Thanks. That site will definitely help. Do you know what the proper names of the small reduction gear and the keyed rod the Jack shaft goes onto is called?
A 5/8" dia shaft with keyway is sold at any length needed or buy the ft,The gears are your choice of chain size and tooth count with the 5/8ths I.D. The set below came from them,415 gear on engine side and 410 drive gear with a 410 freewheel.
 

Attachments

Top