Author Topic: gear selector pinion gear  (Read 193 times)

0 Members and 1 Guest are viewing this topic.

Offline saluki42

  • Full Member
  • **
  • Join Date: Jun 2020
  • Posts: 116
  • Location: Somerset, UK
gear selector pinion gear
« on: 15 Jan 2022 at 11:06 »
Hi again I was wondering if anybody can help me with any information regarding the pinion gear which is driven by the rack in my 1934 4 speed gearbox. This is just about the last thing I need to complete the box build.

Chris

Offline Ian Hand

  • Full Member
  • **
  • Join Date: Jun 2021
  • Posts: 23
  • Location: Tuross Head, NSW, Australia
Re: gear selector pinion gear
« Reply #1 on: Yesterday at 01:49 »
Hi Chris,
I have my gearbox apart at the moment. What information do you need. Here are some photo's which might help.  I am missing the kickstart return spring which I have ordered from the Douglas Spares guy Alan.  I am having difficulty with identifying the model of gearbox without pulling it completely apart. I can identify it a a 4 speed box by the number of detents in the selector shaft but when I attach the foot change I can only select 3 speeds. i guess I will need to pull it apart for a positive ID.
Tell me if you need dimensions and specs for the gear. I can pull it out and give you spme close up pics and measurements that a gear cutter will understand.

Offline Doug

  • Administrator
  • ****
  • Join Date: Mar 2004
  • Posts: 4359
  • Location: Glen Mills, PA, USA
Re: gear selector pinion gear
« Reply #2 on: Yesterday at 05:14 »
Chris,

Are you trying to time it? Is it missing?

-Doug

Offline saluki42

  • Full Member
  • **
  • Join Date: Jun 2020
  • Posts: 116
  • Location: Somerset, UK
Re: gear selector pinion gear
« Reply #3 on: Yesterday at 08:46 »
Hi thanks for the quick replies, unfortunately although I have a collection of gearboxes from the thirties, two rack and pinion selector and three level and slider selection, none of them have that pinion gear either fitted or in the box of parts which came with them.
I have been trying to find a pinion gear for quite some time but without any success so if it comes to it I'll have to see if I can get one made if you could let me have the details Ian.

As far as the timing is concerned Doug I at first wondered what you meant, on reflection of course the pinion and rack have to be set up to synchronies with the gear selector lever and tank plate. I haven't actually got that far yet but now see it's something I'll have to deal with when the time comes.

Thanks again
Chris

Offline Doug

  • Administrator
  • ****
  • Join Date: Mar 2004
  • Posts: 4359
  • Location: Glen Mills, PA, USA
Re: gear selector pinion gear
« Reply #4 on: Yesterday at 17:03 »
There is a center punch dimple on the rack and one of the teeth on the pinion has a small groove cut on it, so timing is pretty easy to read though sometimes takes more than one try to assemble in sync. Not sure if I have a spare pinion, I'll have to look.

-Doug

Offline Dads bike

  • Full Member
  • **
  • Join Date: Jul 2020
  • Posts: 129
  • Location: Norfolk, UK
Re: gear selector pinion gear
« Reply #5 on: Today at 10:27 »
Morning
A picture of the aforesaid.
Note the common failure of this pinion. Brake through the key way.
Cause? possibly over tightening of the retaining nut onto the taper or over enthusiasm in trying to find gears on a static box or maybe both.

Steve

 

motorcycle