86 KDX with 02 KX125 forks

Questions and comments about converting to beefier forks..
Post Reply
pkenney
Supporting Member II
Supporting Member II
Posts: 64
Joined: 11:20 pm Dec 01 2013
Country: United States
Location: Cincinnati, Ohio

86 KDX with 02 KX125 forks

Post by pkenney »

Hi All,

Upgraded my 86 to 2002 KX125 48mm KYBs in early 2017 and got them working pretty good towards the end of the year.
I bought the KX rolling chassis for $100 and the conversion wasn't very difficult but getting the forks to work well was a lot of work.
I was really glad my helmet had a strap the first few rides or it probably would have flown off my head over small bumps they were so stiff.
I ended up with a really unconventional shim arrangement, basically inverted with very light low speed damping but it seems to work well.
Overall a great improvement and fun project.

Some details:
Stock KDX stem was knurled and pressed in with Loctite
Forks were shortened 33mm - measured unloaded axle to lower triple clamp and determine difference
New spring seat and spacer made to shorten forks.
Bladders gone
KX upper triple clamp was machined to accept conical KDX bushing
KX125 wheel, brakes , and fender

Some photos:
970969968967966965959
User avatar
B737driver
Gold Member
Gold Member
Posts: 491
Joined: 01:11 pm Dec 02 2011
Country:
Location: Heath, Texas

Re: 86 KDX with 02 KX125 forks

Post by B737driver »

What a cool bike. I was always s partial to the C’s (86-88). Congrats on the air cooled monster. :supz:

Appears that you have quite the collection.
Live to Fly
Fly to Live
User avatar
KDXGarage
KDXRider.net
KDXRider.net
Posts: 14047
Joined: 06:45 am Nov 01 2004
Country: United States of America
Location: AL, USA
Contact:

Re: 86 KDX with 02 KX125 forks

Post by KDXGarage »

VERY COOL! Thanks for sharing. If you don't mind, how do you like the Craftsman Professional air compressor? I had thought of getting one in the past, but my Craftsman air compressor put out almost as much pressure. I never could pay that much just to be a little more pressure and quieter.


Image

Image

Image

Image

Image

Image

Image
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128
canamfan
Supporting Member II
Supporting Member II
Posts: 444
Joined: 09:55 pm May 08 2011
Country:
Location: butler mo USA

86 KDX with 02 KX125 forks

Post by canamfan »

Great job , disc on the rear too.
pkenney
Supporting Member II
Supporting Member II
Posts: 64
Joined: 11:20 pm Dec 01 2013
Country: United States
Location: Cincinnati, Ohio

Re: 86 KDX with 02 KX125 forks

Post by pkenney »

Thanks for the compliments!
the rear wheel is from the KX125 also.

No complaints on the compressor, it is the quietest I've had and it pumps up quick.

I need to do some spring cleaning. :oops:
User avatar
KDXGarage
KDXRider.net
KDXRider.net
Posts: 14047
Joined: 06:45 am Nov 01 2004
Country: United States of America
Location: AL, USA
Contact:

Re: 86 KDX with 02 KX125 forks

Post by KDXGarage »

Thanks on the compressor report.

I like that you modified the upper clamp for the C cone. That's next level. :bravo:
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128
Jim B
Member
Posts: 284
Joined: 04:17 am Nov 29 2009
Country:
Location: Colorado Springs, CO, USA

Re: 86 KDX with 02 KX125 forks

Post by Jim B »

I've got a 2002 KX125 front end on my '97 220. Love it! :supz:
Last edited by Jim B on 10:18 pm Feb 15 2018, edited 1 time in total.
User avatar
KDXGarage
KDXRider.net
KDXRider.net
Posts: 14047
Joined: 06:45 am Nov 01 2004
Country: United States of America
Location: AL, USA
Contact:

Re: 86 KDX with 02 KX125 forks

Post by KDXGarage »

AH!! Always the question, do the clamps or forks hit the tank on the '87??

I have a Pro Taper upper clamp on my '94, and it took me forever to figure out why I had two little black lines on my tank top. :blink: :lol:
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128
pkenney
Supporting Member II
Supporting Member II
Posts: 64
Joined: 11:20 pm Dec 01 2013
Country: United States
Location: Cincinnati, Ohio

Re: 86 KDX with 02 KX125 forks

Post by pkenney »

I have about 1/2" clearance to the tank so didn't need to modify the steering lock.
Jim, good to hear you love them they are still new to me but it is fun to look for big rocks and other things I used to avoid.
User avatar
KDXGarage
KDXRider.net
KDXRider.net
Posts: 14047
Joined: 06:45 am Nov 01 2004
Country: United States of America
Location: AL, USA
Contact:

Re: 86 KDX with 02 KX125 forks

Post by KDXGarage »

Cool. That is one thing to consider on all swaps.

Do you have an '86 or '87? The seat is from 1987.
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128
ohgood
Supporting Member II
Supporting Member II
Posts: 925
Joined: 10:00 am Jan 04 2014
Country:

Re: 86 KDX with 02 KX125 forks

Post by ohgood »

always neat to see someone taking the time to make things fit perfectly. i had to look twice to see what you were doing with the triple tree. cool ! :-)
pkenney
Supporting Member II
Supporting Member II
Posts: 64
Joined: 11:20 pm Dec 01 2013
Country: United States
Location: Cincinnati, Ohio

Re: 86 KDX with 02 KX125 forks

Post by pkenney »

Thanks, it helps to have machine tools! (And a buddy in the used machine tool business)
I just got the rotary table and this was my first use.

The bike is an 86, I got the seat from another basket case so it might be an 87.
I'm going to put that basket case together for the wife.
Pressingonward1
Member
Posts: 4
Joined: 07:15 pm Mar 12 2019
Country: USA
Location: SW Washington

Re: 86 KDX with 02 KX125 forks

Post by Pressingonward1 »

I have a 1988 KDX I'm looking to upgrade the forks on. Your pictures aren't working, any chance you could repost them?
pkenney
Supporting Member II
Supporting Member II
Posts: 64
Joined: 11:20 pm Dec 01 2013
Country: United States
Location: Cincinnati, Ohio

Re: 86 KDX with 02 KX125 forks

Post by pkenney »

I had trouble posting them before...see if these work.

[img]

[img]
User avatar
SS109
KDXRider.net
KDXRider.net
Posts: 5770
Joined: 05:11 am Aug 23 2009
Country: USA
Location: Tucson, AZ, USA
Contact:

Re: 86 KDX with 02 KX125 forks

Post by SS109 »

Freakin' sweeeeeeeeet! :supz:
Youtube Channel: WildAzzRacing
AZ State Parks & Trails OHV Ambassador - Trail Riders of Southern AZ
Current KDX: '98 KDX220
Old KDX: '90 KDX200 -White/Blue
'11 GasGas EC250R
User avatar
KDXGarage
KDXRider.net
KDXRider.net
Posts: 14047
Joined: 06:45 am Nov 01 2004
Country: United States of America
Location: AL, USA
Contact:

Re: 86 KDX with 02 KX125 forks

Post by KDXGarage »

That looks really good!
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128
Post Reply