Repairing Stripped Kick-start Lever Splines

[PEZBerq]

Giday. 
Does anyone have a successful method for repairing a kick start lever with the fine splines stripped    The shaft is fine (hardened I expect) but the lever is softer and the pinch bolt must have come loose and let it turn on the shaft stripping the splines.
 Other than the sacrilegious welding of the lever to the shaft  is there another way to recover from this drama?  I am thinking of keying the lever to the shaft using a couple of 4mm grub screws but am not sure if the hardened shaft can be successfully drilled and tapped. I could maybe use 4mm pins instead of grub screws to avoid the need for a thread to be cut.  Also not sure if say three grub screws will carry the load without failing.

I could try a new lever I suppose but this is the second time it happened now and its giving me the shits! Any suggestions welcome. Thanks

[holeshot buddy]

you may be able to grind a flat on the shaft
and put a clamp type with a bolt  kickstart on
or a pin on the flat like pushy pedals

[Lozza]

Other than the sacrilegious welding of the lever to the shaft 

Nothing sareligious there been done many times, you never have a problem and was done back in the day on factory bikes by factory mechanics.
You an drill hardened shafts but tapping will be difficult. Putting a through bolt will get more clamping force.
HTH
 

[LWC82PE]

Yeah Holeshot was thinking what i was thinking. Get a  cotter pin from a bicycle crank or a of a british bike kicktarter. Eade Classic All parts in sydney or Union Jack or any brit bike places will have them. Any 60's or 70's triump/BSA/Norton has them. I have found the Taiwanese bicycle crank cotter pins although they are identical in dimensions to the motorbike cotter pins, they are made from a softer material and i had problems with them otherday on a bike where the cotter pin kept wearing and comming loose. the bicycle ones dont seem strong enough for kickstarters.

[pmc57]

You didn't say what bike it is and type of lever, I'm presuming it's one with a pinch bolt style.
If it is, I would continue with using a new lever, just pay attention to detail and make sure the bolt is clamping up properly. It will only wear / flog it self out if it's allowed to come loose, if it is kept tight it will not wear.
Make sure the splines on the shaft are clean and not full of old steel from the old lever.
Make sure the bolt doesn't run out of thread stopping it from being tightened properly.
Use anti-seize compound on the bolt thread and under the bolt head so it can be torqued up to it's potential.
Keep a regular eye on it to make sure it doesn't come loose. Part of regular maintenance.

[Nathan S]

A new lever is the correct answer.

Failing that, the best simple solution I've seen is to bolt the lever on (snug rather than tight), and then drill a hole that removes metal from both the shaft and the lever.
Then get some steel rod of the same diameter as the drill hole, and put it in the hole.
Tighten the lever, and you're sweet!

Basically, its a back-yarder method of cutting a key-way.

[PEZBerq]

Thanks for the ideas.  Its a 78 Husky and it is a pinch bolt tightened lever.  Its the 2nd time its happened now  and I now have a replacement lever on the way. 

I could have sworn I had it right after he first one stripped but obviously not.  I had trouble getting a spanner onto the bolt to tighten it (not enough clearance machined by Husky) so I am going to change to a high tensile capscrew and grind some material off the lever to allow a socket to fit over the nut.  Lots of lube should see it nice and tight.  Also considering getting a compression relief device installed to take load off kickstart assembly and the rider

Nathan were you suggesting drilling the hole axially along the shaft between the lever and the shaft like a round key or radially like a cotter pin on a treadly?  Its only an 18mm dia shaft and the kickstart doesnt have much meat so I cant use too big a pin - 5mm - 6mm dia would be OK,  Maybe do it 3 times.  Here is a photo of the offending item.

[Stan S]

Nathans Idea is a very good one as a temporary repair. I have used this many times over the years mainly on badly worn gear selector shafts/levers but also on kick start shafts/levers. It does require drilling in the end of the shaft between the shaft and lever (round key type) I find a couple of 3 or 4 mm pins usually does the job. I use needle rollers about the width of the lever. Also drill the hole slightly smaller than the pin with the lever clamped up tight, loosen the lever bolt and drive the pins in and retighten the clamp bolt. Should be a good temporary repair.
But be aware once you have drilled your kick starter shaft theres no going back.

I think just fit your new lever with a good quality bolt and keep an eye on it regularly.

Stan.

[pmc57]

PEZBerg
Your pics tell a thousand words.
I agree with you use of a high tensile capscrew, my next suggestion would be to use a fine thread capscrew. Instead of the standard M8x1.25 pitch metric coarse pitch thread, go with a high tensile metric fine pitch M8 x 1.0 socket head capscrew. This will give more tightening power (mechanical advantage).
Also make sure the gap in the lever closes up enough to clamp the shaft securely without binding, going by the pic, it has ample clearence.

Although I see merrit in the "scotch key" method Stan S and Nathan S suggested, I would not like to see a perfectly good shaft bastardised if it was not absolutely necessary. In this case the shaft looks in good condition, so why bugger it. Think about the next owner.

[PEZBerq]

Finally got the kick start problem sorted .  Got a new kickstart lever (kerching ...sound of cash register!  ) and took Husky67's advice and fitted a compression release - thanks Pete . 
Started it today and it was absolutely fantastic.  Like kicking the bike over with the spark plug out!  No strain on the leg and best of all no strain on the feeble splines Husky used for the kickstart lever on these bikes.  The 390 has a high compression ratio - about 12:1 - so its very welcome.  I used a Vulcan Works 14mm long reach release as per Pete's recommendation and it looks great, fits great on the Husky head and is a quality device in my opinion.  Here are some photos for those interested.  I will fit one to my 500 AE very shortly for sure and my 430 XC may even get one.  Had a local machine shop drill and tap the head after taking careful measurements to decide where to fit it. I needed some copper washers to space it out so the release was flush in the combustion dome and didn't protrude or recede - will get a proper spacer machined up later.

[Slakewell]

Just a little tip here
If it's allready F*cked you can first off try the roll pin I normaly go for 5mm one. Now the trick is buy a concrete drill this has a tungsten carbrite tip and will drill the harden shaft might sound a little wacky but it works. drill thou everything and hit in the roll pin then cut off excess.
The crub screw or scotch key way dosent work as taping the harden steel dosent work.
If you are going to weld the sucker do it right. Buy a WIA 316 crome molly rod these are chockers full of chromuim and stick like a bad stain to your best shirt.
Also make sure you have a water bucket ready to stop burning the seal.

[TT5 Matt]

why not go for 2 or 3 roll pins and share the load....justa thought

[Slakewell]

You dont use the roll pins as the spline or drill them in from side you drill all the way thou the kick stater and the shaft one 5mm normaly works. Spray a little water on as you drill.This is also easier what of removing the kick starter as you can punch the roll pin out and replace it afterwards.

[firko]

took Husky67's advice and fitted a compression release

These decompressors have been a well kept secret but I have to agree, they work. I've got 'em on my Maicos, TM400 Suzuki and now have one in my soon to be released Cheney Yamaha. They're a boon for arthritic old codgers with dicky knees like moi who have a hard time kicking big bores into life. Thanks for the lead Husky Pete. 

Call me old school but I still like welding my kickstarter to the shaft. That way there's no possibility of the kicker turning on the spline. If fo some obscure reason you ever need to remove it, a quick hit with an 8" grinder and it's off.