450 selector box question

[graeme]

I took the Scrambler out yesterday to pick up parts for my log splitter.
All good on the way there, and halfway back it stuck in 2nd gear.
The gear lever moved up and down the full distance but wasn’t changing gears.
Felt like the claw wasn’t latching on to the pegs for each gear step.
The it came good again.
I removed the selector box, removed the cover, cleaned the grease out so I can see what was going on.
I think the small light spring that pushes the claw down had moved down partially into the law hole. ?????
Should be a shim / washer under the spring. There is none in this one.

Opinions,,,,??

Main problem is that it works perfectly at the moment.
If it’s not broken I can’t fix it

Graeme

[graeme]

Pic

unknown.jpeg

[Duccout]

Hi Graeme,

I had the same thing happen to me years ago; I fixed it by fitting a thin shim under the spring (possibly a bevel gear shim). I don't know if a shim should go in there, but it solves the problem.

Cheers,

Colin

[graeme]

Hello Colin,
I replaced the bronze bushes in the outer and inner case.
I’m sure I put the mechanism back the same way it came apart and didn’t have any shims / washers left over.
(I’m aware that if you pull something apart often enough, sooner or later you will have 2 of them)
Also fitted a new return spring.
I have fitted a shim for the light spring to sit on so it can’t move into the hole (as seen in the picture)
Time will tell,,,,

Regards
Graeme

[LaceyDucati]

Hi Graeme

No there isn't supposed to be a spring there, but as you have discovered sometimes it benefits from one. I always fit a 0.3 to 0.5mm shim there when rebuilding boxes. I think the later hinged mechanisms are more prone to this issue, due to the slot, rather than the hole of the earlier mechanisms.

Regards Nigel

[graeme]

Hello Nigel,
The light coil spring was there but I think it was falling into the elongated hole in the claw ? As in the picture
And not pushing the claw down to let it grab the pegs.
I fitted a.3mm shim between the claw and coil spring
Seems ok now.
The Haynes manual shows the washer / shim, item 25 or 26

Graeme

[LaceyDucati]

Hello Graeme

Sorry my typo...I meant to say washer not spring Rushed off my reply, without reading it back!

Of course there is meant to be a spring, however no factory parts book I've seen shows the washer. I will check for sure when I get back to the workshop next week and check the Haynes manual. Maybe the Haynes manual took the diagram from a late parts book (which is a rare item). That said I've never found that washer in any original box I've stripped. Albeit they could benefit from it!

Bevel twins with selector boxes, also occasionally suffer the same issue.

Regards Nigel

[graeme]

Page 41 Haynes manual, item 25

IMG_2463.jpeg

Graeme

[Jordan]

Some parts lists show the shim, others don't.
An added item by the factory at some stage?