Author Topic: Billet shift forks?  (Read 2330 times)

0 Members and 1 Guest are viewing this topic.

Offline k9Mike

  • Jr. Member
  • **
  • Posts: 22
Billet shift forks?
« on: September 26, 2019, 04:38:02 PM »
I've seen there's been some work in the recent past to recreate the no longer obtainable shift forks.  I was wondering if anyone knows of progress (or if they are available). So far I've only found a facebook reference to Nova Racing in the UK announcing they have billet shift forks for the KX500 (for ~$222). But there's no reference on their web site.

Thx!

Offline sandblaster

  • Global Moderator
  • Hero Member
  • *****
  • Posts: 8,271
    • OEM-CYCLE QUALITY USED PARTS
Re: Billet shift forks?
« Reply #1 on: September 26, 2019, 05:35:13 PM »
They only have one shift fork available.

http://www.kx500tech.com/

Joe Martin here in the states is working on them.
No ETA
The four stroke engine: That's one stroke for producing power and three for wearing the engine out.

Offline k9Mike

  • Jr. Member
  • **
  • Posts: 22
Re: Billet shift forks?
« Reply #2 on: September 27, 2019, 04:17:35 AM »
Seems like machines are going to start being sidelined for lack of these kind of critical parts.

In my clearly non-expert and uninformed opinion, it appears to simply require a Solidworks guru, a chunk of steel, and a relatively expensive CNC machine.  :-D

Offline motorman455

  • Full Member
  • ***
  • Posts: 118
Re: Billet shift forks?
« Reply #3 on: September 27, 2019, 05:22:30 AM »
Don't they need to be hardened? Seems like billet would be relatively soft and wear quickly.

Offline k9Mike

  • Jr. Member
  • **
  • Posts: 22
Re: Billet shift forks?
« Reply #4 on: September 27, 2019, 05:30:49 AM »
Again, I'm def no expert, but I think hardened steel can be milled/machined.

Offline cwtoyota

  • Jr. Member
  • **
  • Posts: 21
Re: Billet shift forks?
« Reply #5 on: September 28, 2019, 10:18:49 AM »
Again, I'm def no expert, but I think hardened steel can be milled/machined.

The proper way is to machine it in the annealed or normalized state, then heat-treat and grind. 
Hard milling and hard turning are fairly troublesome.

I've done some parts for my other bikes...
Of course, now that I'm into this KX500 thing, I'm considering manufacturing certain gears and forks here in my shop.

Here's an older 1st attempt prototype shift fork for a YZ tranny upgrade I run in my own bikes:



Offline sandblaster

  • Global Moderator
  • Hero Member
  • *****
  • Posts: 8,271
    • OEM-CYCLE QUALITY USED PARTS
Re: Billet shift forks?
« Reply #6 on: September 28, 2019, 03:20:19 PM »
Nice.
Mfg them with a replaceable pin.
After machine and heat treat have them Industrial chrome plated.
Very high lubricity and they will last forever..
The four stroke engine: That's one stroke for producing power and three for wearing the engine out.

Offline cwtoyota

  • Jr. Member
  • **
  • Posts: 21
Re: Billet shift forks?
« Reply #7 on: September 29, 2019, 06:45:58 PM »
Nice.
Mfg them with a replaceable pin.
After machine and heat treat have them Industrial chrome plated.
Very high lubricity and they will last forever..

Hard chrome like that stocker would be a good idea for production.
I thought about doing replaceable pins on those YZ forks, but there's not much meat there for pin-bore depth (less than a diameter).
There's a nice generous radius where that pin meets the body of the fork.

I throw out the stock cross-drilled, hollow rod (or rail) and replace it with the longer solid tool-steel rod.  They don't flex or bind like the OEM ones.