The kicksarter is a bit loose on its spindle, no matter how hard I tighten the bolt.
You could do away with the threaded bolt and just use a longer bolt with a spring washer and nut to tighten the kicker up and could use a undersize bolt and nut system the tighter you can get the cut spline on the kicker the better it will work, I used the longer bolt and nut on my kicker for over 30 years and it worked good, but still had to tighten it every so often but not all the time, but since putting the RGM folding kicker I haven't had any problems with a loose kicker.I found that widening the slot worked up to a point after which the clamp would only tighten just so far before the ends became distorted enough to jam the bolt.
The (oversized) bolt in the picture below is fully tightened but the distortion is literally bending the bolt causing the threads to lock solid. The cure in this instance was a new kickstart lever.
You could do away with the threaded bolt and just use a longer bolt with a spring washer and nut to tighten the kicker up and could use a undersize bolt and nut system the tighter you can get the cut spline on the kicker the better it will work,
A two foot bar might be a little over the top even for a grade 8 3/8" bolt. I've just spent a morning breaking rusty grade five bolts on an old pickup fender. It took a long 9/16 combination spanner wedged against the frame and an 18" bar. I use a grade 8 bolt and two nuts on my Matchless KS lever. Tightening as much as I dare it still works loose. I like the grind a couple of splines method. I think I'll try that.Peter R wrote: "The kickstarter is a bit loose on its spindle, no matter how hard I tighten the bolt."
Different people have different ideas of what tight is.
Assuming the splines are compromised but not totally buggered, I would replace the bolt with a grade 8 bolt, and use a two foot breaker bar to tighten it just short of shearing.
If that doesn't work, time for some new parts.
More HOW MUCH to use ... 2002 on our way out to the Norton Rally in British Columbia my buddy had the kick start strip the splines out enough that no matter how much you tightened it , it would just spin around .. This all happened around 4:45 pm in a small town .. By good luck there just happened to be a shop down the street that just happened to have a welder.. Seeing as the splines on the shaft were still ok we decided to keep the kick start out to the end and welded it to the end of the shaft .. Worked like magic .. When he got home it was just a matter of grinding of the weld and installing a new kick start .Don't forget the last ditch option: weld the sucker on!
Hmm, now what rod should you use?