Thank you, Yves.

Bonzo · 2026-03-26T12:35:01-0600

Our youngest lad, Michael is a pretty gifted engineer and so I asked him if he fancied a challenge!

Nearly a decade ago, Yves posted the following thread for his fix for the Alton ES / woodruff key issue...

Thread 'Alton starter my solution for broken woodruff key (2017)'

Nov 25, 2017

Broken woodruff key is a problem with alton starters because the sprag weel is only sandwiched and the power come on the key, and the key is not made to hold the power and will brake after a while.
The solution is to make a connection between sprag weel and the triplex sproket.
Here is wat I did:
1: make two flats on the sprag weel

2: Make a new spacer with two inserts that go over the two flats from the sprag weel
The right piece is the original Alton spacer, the left one is the new one,
don't look at the two big holes, I will explain this later

3...

I printed off Yves' diagram and showed Michael a few photo's and gave him a few Alton parts and off he went.

First off, following Yves' dimms, he made the flats on the Alton sprag, and then made a milled out spacer followed by a couple of 5/16" sharpened grub screws, for me to assemble onto the crankshaft with the woodruff keys, and 'mark' prior to drilling.

Today, he sent me a text saying "ready for collection".

Bonzo · 2026-03-26T12:37:52-0600

Thank you to Yves for dreaming this all up, and a special thanks to Bonzo Jnr.

Proud Dad

MichaelB · 2026-03-26T15:33:24-0600

Nice Work!!

Thank you, Yves.

Bonzo

Thread 'Alton starter my solution for broken woodruff key (2017)'

Bonzo

MichaelB

"Sons of Arthritus"

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