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Discussion Starter · #1 · (Edited)
So I took a look at the shifter, shifter rod and shifter arm that attaches to the engine. The shifter arm hole measures .279. The shifter rod measures .272. The hole in the shifter arm that attches to the engine measures .297, that is .025 thousands bigger. That is the source of the majority of the slop in the shifter and will only get worse over time. I am going to see if I can find a bushing at the hardware store to fix this and give it the same .007 clearance the shifter rod has where it goes thru the shifter. The slop in the shifter is 3/8" just because of this clearance. Hopefully a new bushing will cut that in half. Unfortunately I am going to have to make one.
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While it can be fun to tweak and improve things on our bikes, it may be worth it in the end to simply buy an IMS or TB shifter, and ditch the linkage all together.

 

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Discussion Starter · #3 ·
That is definitely a better idea and will require less work on my part. The only reason I could figure for the linkage was to protect the shift shaft in the even of dropping the bike since it is marketed to new riders. That will definitely get rid of the slop! Thanks!
 

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Discussion Starter · #5 ·
The problem is the hole in the arm that bolts to the splined trans shaft is too big. The other hole in the shifter lever is only .007 bigger than the linkage rod. Its a manufacturing issue.

The rose joint shift linkage improvement kit appears to use identical size bolts which doesn't fix the oversize hole issue in the arm that bolts to the splined trans shaft.

I can tighten up the clearance by making a bushing that is a tight fit on the linkge rod and a slip fit on the arm that bolts to the splined trans shaft.

I know it is my labor to do it but I enjoy making things and have access to a machine shop to make a bushing. If it doesnt work I can always buy the direct shifter in the second post.
 

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Scrap the linkage all together. Huge difference. The linkage is there because it’s cheap to manufacture, not to protect the shift shaft…..
 

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Discussion Starter · #8 ·
I coated the linkage ends with wheel bearing grease and reinstalled it and measured. The freeplay before the splined shaft moves went from 3/8" down to 1/8". The shift feel now is almost like a normal motorcycle and you can't really feel the slop with your foot.

I was measuring at the end of the shift lever. I spent $4 at Westlake Hardware on a 1" long steel bushing 3/8" OD, 1/4" ID and drilled the ID out to .277 then cut a piece off the end of the bushing about 1/4" long. Then I drilled the hole out in the shifter arm to 3/8" and pressed the bushing in it and ressembled like normal with new cotter pins.

For $4 and my labor I am happy with the result. I used a lathe to drill the bushing out and cut a piece off the end. I used a drill press to drill out the shifter arm and a small brass hammer to tap the bushing into the arm.
 

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The rose joint shift linkage improvement kit appears to use identical size bolts which doesn't fix the oversize hole issue in the arm that bolts to the splined trans shaft.
I like how you think, I too like to tinker, but it's usually on things that make them go faster......
The kit I linked has the benefit of being able to tighten the bolts to eliminate the slop, rose joints will still rotate inside.... I bought the parts separately in town, but the next size up and drilled the shifter and shift shaft arm accordingly for my girls bike, zero slop. Worked great for her until she started getting faster trying to keep up with me and started dragging her toes around corners. Rearsets came next, and they have ZERO slop also, with the benefit of WAY MORE clearance in turns.
 

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Discussion Starter · #10 ·
I like the idea of the linkage in case the shifter gets bent. I remember dropping my first bike and bending the shifter and it bent slightly the shift shaft it was attached to. Then it was hard to shift. Luckily for me a friends dad knew how to split the cases and replaced it for me. That's why I thought the linkage was there to protect the shifter arm.
 

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I like how you think, I too like to tinker, but it's usually on things that make them go faster......
The kit I linked has the benefit of being able to tighten the bolts to eliminate the slop, rose joints will still rotate inside.... I bought the parts separately in town, but the next size up and drilled the shifter and shift shaft arm accordingly for my girls bike, zero slop. Worked great for her until she started getting faster trying to keep up with me and started dragging her toes around corners. Rearsets came next, and they have ZERO slop also, with the benefit of WAY MORE clearance in turns.
What brand rearsets did you put on ?
 

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I like how you think, I too like to tinker, but it's usually on things that make them go faster......
The kit I linked has the benefit of being able to tighten the bolts to eliminate the slop, rose joints will still rotate inside.... I bought the parts separately in town, but the next size up and drilled the shifter and shift shaft arm accordingly for my girls bike, zero slop. Worked great for her until she started getting faster trying to keep up with me and started dragging her toes around corners. Rearsets came next, and they have ZERO slop also, with the benefit of WAY MORE clearance in turns.
This has been my experience too. I’m running the Kitaco linkage kit, along with the Hard Racing shifter shaft support. Zero slop. If I drop the bike, I feel like it is better protected. My buddy has a shifter mounted directly to the shaft. He seems happy with it. I’m happy with my setup, too.
 
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