Tips/ideas/help for fabricating shift lever

[Crim]

So, this is sort of a weird non-cafe type question, but I know there are a lot of hardcore builders on here.

I'm working on an engine swap (KX125 into Aprilia RS50 frame) and the 2 stroke engine is pretty narrow compared to the frame. I need to extend the transmission lever straight out from the crankcase about 3-4 inches to hookup to my rear sets. Ideally it would be a straight shaft that slipped over the splined shifter shaft coming out of the crank case, and the other end was splined for my rear sets to clamp onto. Anyone ever fabricated a shift lever? Whats the best way to do this or any suggestions? I suppose I could always hack up the stock KX125 shifter, but that only gets me one half of the shaft.

Thanks
Stephen

 

[teazer]

There are several way to do it and I have only tried a few of them. Without seeing your particular application, it's hard to recommend one way or another. But just to get you thinking, here's a couple.

On a CB77 HAwk 305 I cut the lever off and welded a flat 3mmx25mm steel strap to teh lever to extend the shaft and at teh end, I net it 90 degrees and used a heim joint.

On a CB160 I needed to extend a shaft so I cut the shaft, drilled both end, inserted a steel pin and and extension and had it all silver soldered. Actually I had a machinist do it...

You could use a shift rod with a pair of bends in it, but that will tend to bend when you stand on it to shift gears.

You could sue the TZ approach of having a short lever pointing back that engages in a rocker arm which allows the shift lever to be mounted further out.

You could cut the ever part off an existing shift lever and weld on a short length of say 1/2" steel tube split at the shaft end. Weld a short "lever onto the outer end of that tube and use a shift rod to link it to the shift lever.

Post a pic and that will help us to make more targeted suggestions.

 

[crazypj]

Not sure of spline pattern but you may find an internal semi-auto clutch operating lever from ATV that will fit.
Some use extended shaft but others have a tubular piece.
I'll see if I can find any pics

 

[Crim]

I think the most obvious solution would be to cut off my KX125 shift lever, weld on a 3 or 4" tube and then a pivot point to attach to my rear set rod. However, all my previous attempts at tig welding cast aluminum have ended poorly, so I'm avoiding this solution if possible.

 

[Crim]

Heres a picture, you can see there is ~ 3-4" of distance between the rearset and where it needs to mount.

 

[teazer]

I like that ATV suggestion. I hadn't thought of that one. There are not a lot of spline patterns, so I would expect it would be relatively easy to find something that could be adapted.

Try an old steel shift lever and add a thick enough wall tube to it.

 

[crazypj]

Kawasaki use same spline pattern on most of their bikes, get a steel lever and weld tube to it.
I would fit some type of outrigger bearing as shaft looks a long way in from frame

 

[Crim]

Kawasaki use same spline pattern on most of their bikes, get a steel lever and weld tube to it.
I would fit some type of outrigger bearing as shaft looks a long way in from frame

Hmm support bearing along the shaft, that's an excellent idea I had not thought of. I'll probably do this. I'll try to dig around on some kawa forums to find a steel lever.