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Spline Bit

 

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Anyone had the splines worn down on their Harley forward control gearshifter?

Just wondered if anyone else has encountered the spline wearing out thus being unable to change gear or have great difficulty trying to.The allen screw tightens right up but the gear lever still rotates on the splines.Anyone got any suggestions for a Mod rather than buy another linkage? I've tried taking the screw out and putting a nylock nut and bolt through for extra tightness but still no joy.Maybe I could clamp the splined gear lever a little bit in a vice?

If you've got any splines left on Both the shaft and the lever,,,
Simplest thing to do is
*remove the lever,,,
*pinch it ALMOST "closed" in a vise
(You can put a shim in the gap to pinch down on,,,,a slice of aluminum soda/beer can.)
*Run a hacksaw Through the original gap.
It's self-guiding due to the gap,,,especially if it has a soft aluminum "spacer" in the gap.

That results in a Wider Gap in the lever,,
which prevents it from bottoming out on itself and "closing" before is is able to apply enough clamping force onto the Shaft.

LOOK CLOSELY FIRST,,,and see if your lever's gap is "closed" when fully tight.
If it IS,,,then the above method is the proper solution.

The Principle is same as trying using your Fingers to make an "OK" Sign,,,where Thumb & Forefinger form a Circle.
You Cannot "clamp" a finger on your Other hand in that circle because it's Too Big.
But you CAN clamp down on your Wrist.
When you try it on your wrist,,,you'll see a OPEN GAP between thumb and forefinger.
But when you try it on another Finger,,,the Gap is CLOSED.

Step 2>
If the Pinch Bolt on the Lever screws into Threads on the lever itself,,,
Modify that.
Drill the threads OUT to make a full Through-Hole.
Then use a Nyloc nut .
It sounds like you already Have that,or have done that?
MOST of those are 1/4" Hardware.

Drill a Bigger Hole,,,for 5/16" hardware,,,or even 3/8" if you have enough material in the area.
Most BLACK Allen Headed Bolts are Grade 8....Hi Strength.

Most Plated Allen Head Bolts are Grade 5 or Lower.
Which is Marginal Strength at best.

Your Choice as far as appearance,,,
but a Grade 8 or better Hex Head Bolt offers "best gaurantee" of getting the level of clamping force you need.
At least in terms of KNOWING what you are getting.

Allen Heads are Fine,,,IF you can be certain of its grade.
That's the only Tricky Part.

Stainless hardware is Nice,,but generally not very strong.

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The various methods of Keying,Shimming,Cross-Pinning,Welding all CAN work.
But it's hit-or-miss and can end up with Additional or Worse problems.

I realize that Many people Do those things,,,and it works for them.

I've dealt with several THOUSAND splined shaft/lever connections over several decades.
More times in any given week than most folks face in an entire LIFETIME.
And had to GAURANTEE satifactory results at the risk of Food Off my family's table.
Plus assume the Liability for any mishaps or consequential damage arising from "jerry rigging" something.

Which gives me a bit of a different perspective than folks who patch-up their own bike occasionally.

You can Spot weld it.
You can Drill a whole thru the entire thing,,drop a carpentry nail thru it and bend it over.
You can SMASH the Shaft "Oval" between 2 big hammers.
You can wrap the shaft with a slice of Beer Can "Shim" & hammer the shaft on.
You can drill a hole in END of shaft,,,half & half in Shaft & Lever and Hammer/Thread/Screw/Jam anything in there from a Sheet Metal Screw to some of your GF/Wife's plated steel jewelry.
Pull a boot nail outa the heel of your riding boot,,loosen the bolt,,jam that in,,the retighten.
Epoxy works for a while,,,i've seen That several 100 times.
Etc,Etc,Etc.

I know and have seen just about every "home-made" solution imaginable.

Fish hooks.
Firearm Cartridge Cases.
Shaft wrapped with TAPE of every description,,
and PAPER...matchbook covers.
Sandpaper,,Valve Grind Compound, Lathe Chuck Rosin,Barbed Wire,House Keys,wrapped with electrical wire,WOOD,,matches,toothpicks

Splines are a comparatively expensive machining /manufacturing process.

Mfgrs chose to use that method for specific reasons.

The "correct" repair is to Replace the parts.

Often,,that's not really "good enough" because there are shortcomings with SPECIFIC EXAMPLES.

In Those instances,,,appropriate Modifications are in order.

But despite all the endless creativity possible to get a solid connection,,,
the Best approach is to maintain the splined connection integrity.
A) ensure that the Lever actually CAN clamp the shaft properly,,,without bottoming out on itself.
B) Increase the pinch bolt clamping strength And force.
C) An always WISE mod is to use a Through Hole rather than a Blind ,Threaded hole.
So If/When the bolt Breaks,,,it falls out & is ready for a simple Drop-In replacement.
Rather than fighting to remove a broken bolt.

Result is that everything then functions as it's Supposed to.
You can Tighten it in the future.
You can Remove & Re-install it any time ya need to.
No Damage is done in event of failure.

The fans of Cross Pinning always seem to not mention the result of a pin shearing and and creating a blind-locked groove that requires FURTHER DAMAGE to disassemble and repair.
Or maybe they just havent had it happen to them yet.
A Few out of every 100 become a nightmare.

You DONT wanna paint yourself into a corner,,and find yourself Forced to replace Parts which may be Expensive,Hard to Replace,or Hard to even Find.

"Patch" it properly to begin with and you'll not likely face that possibilty.

Just for grins,,,notice the Gap on shift levers ,kickstart levers on various bikes.
They are always sorta narrow.
Compare it to the gap on splined levers on brake foot pedals,,,and on drum brake actuating levers.
They're Always rather wide in compassion.
Thats no coincidence.

The Factory Engineers spec that extra gap to avoid Brake components from failing due to slipping /loose spline connections due to the gap bottoming out before connection becomes clamped tight enough.
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NO offense intended towards anyone else's advice/methods.
I've used most all of them myself in various circumstances over the years.

And if You're Shaft/Lever happens to have severe spline damage( Like,Smooth or GONE),,,,
then the Other Advice becomes Great Advice to keep from having to replace parts.

You always gotta do what ya CAN,,,and do what ya Gotta do.

Some of the Shakiest methods are sometimes the ONLY method that'll get ya Home.
And that's Never Bad.

Do it GOOD when you Can,,
do whatever it takes the rest of the time.

Good Luck with it.

The Marriage of Fractals and Splines


 

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