ElectricMotorcycleForum.com

  • May 07, 2024, 05:45:03 AM
  • Welcome, Guest
Please login or register.

Login with username, password and session length
Advanced search  

News:

Electric Motorcycle Forum is live!

Pages: [1]

Author Topic: Stripped left lower fork casting emergency  (Read 500 times)

nicktulloh

  • Full Member
  • ***
  • Posts: 151
    • View Profile
Stripped left lower fork casting emergency
« on: March 22, 2021, 12:02:52 AM »

I wouldn't have thought this possible but I have managed to strip the female threads for my front axle (left lower fork casting) on my 2018 DSR.

Anyone have any ideas?
Logged

Kappi

  • Jr. Member
  • **
  • Posts: 75
    • View Profile
Re: Stripped left lower fork casting emergency
« Reply #1 on: March 22, 2021, 01:41:53 AM »

Is there still material left? If so, and the thread is just mangled, perhaps you can re-cut the threads.
Logged
1992 Yamaha FZR 1000
1996 Honda CB "Two Fiffty"
2017 Zero SR 13.0 (14.4)

Say10 15FX 16FXS

  • Sr. Member
  • ****
  • Posts: 367
    • View Profile
Re: Stripped left lower fork casting emergency
« Reply #2 on: March 22, 2021, 02:36:47 AM »

If there are no salvageable threads, you can use a Heli coil insert. This should be easy to do since the fender is removed you should be able to turn the lower leg for easier access.
Logged

Biff

  • Full Member
  • ***
  • Posts: 129
    • View Profile
Re: Stripped left lower fork casting emergency
« Reply #3 on: March 22, 2021, 11:14:09 PM »

Wow, I think that is an M20 x 1.5mm pitch thread,  that takes some serious torque or abuse to completely strip out.  There is a helicoil kit for it, but it costs $500: https://www.fastenal.com/products/details/11133735

I can think of a couple other hack-like ways to fix it, but they are too sketchy to post on a public forum. That joint is pretty critical, I would really recommend it get repaired properly, or replaced.
Logged

Richard230

  • Hero Member
  • *****
  • Posts: 9501
    • View Profile
Re: Stripped left lower fork casting emergency
« Reply #4 on: March 23, 2021, 03:52:53 AM »

Perhaps a new fork tube might cost less than a Helicoil kit?
Logged
Richard's motorcycle collection:  2018 16.6 kWh Zero S, 2009 BMW F650GS, 2020 KTM 390 Duke, 2002 Yamaha FZ1 (FZS1000N) and a 1978 Honda Kick 'N Go Senior.

Say10 15FX 16FXS

  • Sr. Member
  • ****
  • Posts: 367
    • View Profile
Re: Stripped left lower fork casting emergency
« Reply #5 on: March 24, 2021, 04:15:53 AM »

https://www.af1racing.com/DS-FORK-41MM-LEFT-ZM22-08061

$450

I would slide the leg out and take it to a good machinist. If they already had the heli coil kit it might be less. Or they may have another solution. Good luck
Logged

TheRan

  • Hero Member
  • *****
  • Posts: 1479
    • View Profile
Re: Stripped left lower fork casting emergency
« Reply #6 on: March 24, 2021, 08:26:06 AM »

$500 is way overpriced, should be closer to $300 for a kit. Most of that cost is in the tool and tap, you could buy a pack of helicoils for under $50 and take it to a machine shop to get it drilled and tapped and they should be able to whip up a tool easily too if they don't already have one (it's just a rod with a slot in the end).
Logged

rayivers

  • Hero Member
  • *****
  • Posts: 502
  • electric feels so right
    • View Profile
Re: Stripped left lower fork casting emergency
« Reply #7 on: March 24, 2021, 06:51:12 PM »

Is there still material left? If so, and the thread is just mangled, perhaps you can re-cut the threads.

+1.  I recently had a non-MC stainless-on-stainless galling incident where I was sure the threads were toast, but after running a tap through them they're holding fine.

Just fwiw, none of the motorcycles I've owned have used fork axle threads.
Logged
'14 Zero FX 5.7 (now 2.8, MX), '14 Zero FX 2.8 (street), '19 Alta MXR, '18 Alta MXR, various '74 - '08 ICE dirt bikes

Richard230

  • Hero Member
  • *****
  • Posts: 9501
    • View Profile
Re: Stripped left lower fork casting emergency
« Reply #8 on: March 24, 2021, 08:11:11 PM »

The few times that I have had to deal with stripped threads on an engine the shop mechanic always used a product called "Time Sert" (or something very similar).  I have suspicion that product is much cheaper than a Helicoil and that is why they use it.
Logged
Richard's motorcycle collection:  2018 16.6 kWh Zero S, 2009 BMW F650GS, 2020 KTM 390 Duke, 2002 Yamaha FZ1 (FZS1000N) and a 1978 Honda Kick 'N Go Senior.
Pages: [1]