The spline is to suit the manufacturing method. A dividing head has 40 turns to one revolution of the chuck.
ET: Engine (Twin) Stripped Splines on Kickstart Shaft and Lever (Weep)
- Thread starter AndyBee
- Start date
I suspect it will last a quite a few years more.
Steven
Steven
All - thank you very much for the comments and insights. I'm amazed at the amount of experience there with rectifying this issue. I think I'm going to do two things:
1. Purchase a new shaft and lever and fit those for now - as that's a relatively quick job and I can do it myself
2. Look to find someone who can weld and either re-spline or pin my existing lever, so that I'll have a solution 'in my back pocket' in case of another failure in the future - a case of 'be prepared'.
I'm still getting to grips with trustworthy parts suppliers and engineers for these bikes, so I'd rather take my time on point 2 than be too hasty.
1. Purchase a new shaft and lever and fit those for now - as that's a relatively quick job and I can do it myself
2. Look to find someone who can weld and either re-spline or pin my existing lever, so that I'll have a solution 'in my back pocket' in case of another failure in the future - a case of 'be prepared'.
I'm still getting to grips with trustworthy parts suppliers and engineers for these bikes, so I'd rather take my time on point 2 than be too hasty.
Andy it's your call,
But there can be nothing more simple , Than drilling half in the shaft and half in the lever,
And fitting a hard roller,
If you do it with the pinch bolt loose , It will be nice and tight when you nip it up,
The other way you will have to take the Exhaust off, That can be a big problem in it's self,
We had a case the other day , Where a chap took the cover off and dislodged something on the gear selector, Just my thoughts.
Have you seen the price of these things ??.
Good Luck, Bill.
But there can be nothing more simple , Than drilling half in the shaft and half in the lever,
And fitting a hard roller,
If you do it with the pinch bolt loose , It will be nice and tight when you nip it up,
The other way you will have to take the Exhaust off, That can be a big problem in it's self,
We had a case the other day , Where a chap took the cover off and dislodged something on the gear selector, Just my thoughts.
Have you seen the price of these things ??.
Good Luck, Bill.
ray Elder has a broach and did one of mine a few years ago, he seemed willing to carry on broaching kick start levers until the broach wore out.
stumpy lord
When thinking about repairs, well, when you are in mid-seventies, any bodge will be allright possibly. Otherwise you better go for a decent repair. Remember: Do it right - or do it twice.
When you think about that kickstart joint, there is not just a torque onto the shaft that any design has to stand, but also a heavy bending load as the lever folds out of plane when kicking. So any kind of joint that does not fit perfectly all around the shaft will get mangled in time, no matter how much you try to nip up the pinch bolt.
For a good repair I think the conical square trough hole is the easiest idea. Certainly you have to weld up the lever in the stripped spline to work on the square shaft - and weld up the slot as well . Find a company which does wire spark erosion, sink erosion when you provide the copper electrode. Wire spark erosion is even simpler for you, just drop them your lever with a sketch of sizes, one degree taper sides. Most people think spark erosion is space technology, in fact a Russian couple Romanowitsch invented it in 1943 for technical uses and Agie in Switzerland presented wire erosion in 1969 for cutting metal and since this is standard in many companies in toolrooms in plastic injection molding or sheet metal forming and punching. Cutting out the conical square should not be much more than € 100 - 200 , programming and setting up is minimal, you pay for a little electric power and used up wire.
The conical kickstart shaft is easily done on the oldest Bridgeport or China machine, just get a decent dividing head for machining four sides set at 1 degree on the mill head. Aim for a step on the taper that provides the final position when you really fix the lever on the bike. So you get a definite "press fit" finally that you can disassemble one day without offensive language.
Harleys seem to have same square lever design like I wrote above, conical at that ?? A parallel square fit is not what I´d like as it will wear faster with some play from new by design.
Yes, fine adjustments are not possible with this or other designs, so you care for getting your desired position of lever right. Not a big deal I say, you want the lever up-stop just clear of the footrest and this is not particularly critical. With the conical square joint you could try first for best orientation while there is a bit of oversize left on the shaft and procede from there after trial fitting. Simple.
I had my R 69S for 50 years now, with push bike taper pin lever, same with Guzzi singles, never had any desire for fine setting the lever - and never a loose fit of taper pin or lever.
The Vincent Phils were a bit too obsessive with configurations of levers and all I think. But then, this was a sales argument for finding customers willing to pay a very high price - with some consequences from this later in life.
Vic
When you think about that kickstart joint, there is not just a torque onto the shaft that any design has to stand, but also a heavy bending load as the lever folds out of plane when kicking. So any kind of joint that does not fit perfectly all around the shaft will get mangled in time, no matter how much you try to nip up the pinch bolt.
For a good repair I think the conical square trough hole is the easiest idea. Certainly you have to weld up the lever in the stripped spline to work on the square shaft - and weld up the slot as well . Find a company which does wire spark erosion, sink erosion when you provide the copper electrode. Wire spark erosion is even simpler for you, just drop them your lever with a sketch of sizes, one degree taper sides. Most people think spark erosion is space technology, in fact a Russian couple Romanowitsch invented it in 1943 for technical uses and Agie in Switzerland presented wire erosion in 1969 for cutting metal and since this is standard in many companies in toolrooms in plastic injection molding or sheet metal forming and punching. Cutting out the conical square should not be much more than € 100 - 200 , programming and setting up is minimal, you pay for a little electric power and used up wire.
The conical kickstart shaft is easily done on the oldest Bridgeport or China machine, just get a decent dividing head for machining four sides set at 1 degree on the mill head. Aim for a step on the taper that provides the final position when you really fix the lever on the bike. So you get a definite "press fit" finally that you can disassemble one day without offensive language.
Harleys seem to have same square lever design like I wrote above, conical at that ?? A parallel square fit is not what I´d like as it will wear faster with some play from new by design.
Yes, fine adjustments are not possible with this or other designs, so you care for getting your desired position of lever right. Not a big deal I say, you want the lever up-stop just clear of the footrest and this is not particularly critical. With the conical square joint you could try first for best orientation while there is a bit of oversize left on the shaft and procede from there after trial fitting. Simple.
I had my R 69S for 50 years now, with push bike taper pin lever, same with Guzzi singles, never had any desire for fine setting the lever - and never a loose fit of taper pin or lever.
The Vincent Phils were a bit too obsessive with configurations of levers and all I think. But then, this was a sales argument for finding customers willing to pay a very high price - with some consequences from this later in life.
Vic
Vic,
You are quite right about the bending motion because of the heavy load. Before I made my replacement shaft in 4130 I first made it in 303 Stainless. I noticed this had started to take a bend a bit too late. I had to use a cut of wheel to get the shaft out of the outer cover. Not happy with myself over that.
Steven
You are quite right about the bending motion because of the heavy load. Before I made my replacement shaft in 4130 I first made it in 303 Stainless. I noticed this had started to take a bend a bit too late. I had to use a cut of wheel to get the shaft out of the outer cover. Not happy with myself over that.
Steven
A friend of mine had a vertical shaper. I had him make a new spline. I think some people have a broach to make this spline as well. I didn't do any welding I just squeezed the end so it was small enough to have the new spline put in. I think I welded the lever onto a tubular mandrel that was mounted onto the rotary table. I had a used shaft that was OK. The spline when it is in good shape and is held by a very tight grade 8 pinch bolt can last for years (57 years according to Peter) The spline is a bit small, but it works.