2 speed jackshaft won't shift

I have 2 Trailhorse's one with a brand new 2 speed and one with the original 1970 2 speed and nether of them seem to shift. Not sure if the Rmp's or speed isn't getting up high enough to shift? Both have new predator engines. Any ideas. Thanks
Bryce this is on my list also. I have a Trail Horse for the wife and purchased a 2 speed for it at Andy's suggestion and have no clue how to set one up so I am following along.

I am all ears.

Thanks for bringing this up as I would have to ask the same questions.

The only advice I can offer is the jackshaft has to spin at enough rpms to engage that Clutch. So, plug your info into the comp cams gear ratio sticky in the engine thread. It will give you jackshaft RPM. Then, maybe a spring adjustment?
My original sears super 2 speed showed, but it wasn't really noticeable other than you kept picking up speed.

Sent from my iPhone using Tapatalk


Well-Known Member
They usually dump into 2nd a lot sooner than you want them to when working correctly :laugh: I would check that you put the 1st gear on in the correct rotation. If you packed it full of grease thats gotta go, If you just bolted it on off the shelf that its been sitting on for the last 40 years, the old hardened grease has to be cleaned out so it can free wheel easy as well. I use a little grease-just enough to thin coat the pieces during assembly but use an old style oiler can to get some oil down into it when all assembled, and oil it that way often.

on the 2nd gear/clutch There are 2 positions it can go in:

Of course good alignment, spacing, and chain play are a big factor in how it perfoms as well. The only dual gear clutch available anymore is from max torque, and I dont think it lines as good as the original comet made clutches, it still works but its a little more tedious to set up.