Hybrid Update

Discussion for swapping a KDX motor in a MX frame...
Post Reply
User avatar
doctord23
Supporting Member
Posts: 323
Joined: 01:29 pm Jul 28 2009
Country: USA
Location: NorCal

Hybrid Update

Post by doctord23 »

I grew a little tired of the old style look of my 2002 so I made some changes after a couple of seasons.
Especially boring considering that I built another one of the same frame style.
Here is the original look right after the build:
Image

Here is the update. Nothing fancy, but a little newer look.
Image

I used 2004 KX250f gas tank and shrouds with 2003 KX125 seat, airbox, side plates and rear fender.
I modified the 2002 KX rear subframe to work with the 03 parts.
I have also been working on another option where I use the KX250f rear subframe, with airbox, rear fender and number plates with an 03 KX125 seat but that will come later on my 01.

I read that the 99-02 KX plastics couldn't be swapped to anything else and I tried a lot of combinations of tanks and seats until I came up with this one. FYI, 2003 KX tank is a non-starter on this frame.
2002 is the last year of the green sticker bike here in California so I am sticking with it.

Let me know what you think.
My Team Green:
2002 KX-KDX 220
2000 KDX 220
2003 KLX 300 DS
1988 White KDX 200C3
1984 KX500 (original owner)
1996 Honda Magna V4
2017 Honda Africa Twin DCT
User avatar
Tedh98
Supporting Member II
Supporting Member II
Posts: 1576
Joined: 01:08 pm Mar 20 2009
Country:
Location: Atlanta, Georgia
Contact:

Re: Hybrid Update

Post by Tedh98 »

I like it, looks good.
User avatar
bufftester
Platinum Member
Platinum Member
Posts: 3455
Joined: 06:03 pm Oct 31 2012
Country: USA
Location: University Place, WA

Re: Hybrid Update

Post by bufftester »

Hey doc, first thanks for the input about the carb boot and using the KDX boot lip. Is working great on my hybrid and was WAY easier than fabbing up adapter plates, or aluminum rings.

Second...what brand, year and model bike is your kickstand for? Promoto billet doesn't make one for the 99-02 KX's, but that one looks like it fits nicely using the lower roller/subframe mounts. I was almost ready to buy one for a KX500 and redrill it, but I'll wait and see what you have to say first.

I like the look, but the 99-02 KX tank is a meager 2.25 gal, and the 250f is even smaller at 2.0 gal...how much impact has that had on your range?
Thanks again
User avatar
doctord23
Supporting Member
Posts: 323
Joined: 01:29 pm Jul 28 2009
Country: USA
Location: NorCal

Re: Hybrid Update

Post by doctord23 »

I used a Promoto kick-it that fits an 2004 YZ450f.
The top mounts to the bottom subframe bolt and the bottom uses the lower roller, but I had to fabricate a small adapter piece from the roller bolt to the bottom kickstand bolt. Pretty easy to make it fit.
I think an 03 and up KX125 would work the same way.

As for the tank sizing, you are correct. I did loose a little capacity.
I bought a 2.3 gallon KX250f tank that fits really well except that it hits the stem for my steering stabilizer. I'll figure out how to make it work though.
Most of my rides are loops where I can easily make it on 2 gallons and I have an original KDX for the longer rides if I need it.
My Team Green:
2002 KX-KDX 220
2000 KDX 220
2003 KLX 300 DS
1988 White KDX 200C3
1984 KX500 (original owner)
1996 Honda Magna V4
2017 Honda Africa Twin DCT
User avatar
bufftester
Platinum Member
Platinum Member
Posts: 3455
Joined: 06:03 pm Oct 31 2012
Country: USA
Location: University Place, WA

Re: Hybrid Update

Post by bufftester »

Thanks for the info. The only issue I was concerned with on the 03 and up kick it was that the lower subframe mount sits higher on the frame than on the 99-02 frames. Looks lie the 04 one you have is a closer fit. I have been thinking of ebaying an IMS or clarke for my 01 hybrid. Half of my riding is loops where the KX tank is a non-factor, and half are out and backs in the desert where i'd like to not have to carry spare fuel. If I can get the larger tank to work then I'd just swap them depending on where I'm heading.

Haven't seen the fit of the 2.3 gal 250f tank, is it something you can work out with the heat gun? Are you running a bolt-on or welded tower mount on your damper? I've looked at the Scott's, and my dad runs a WER, but I'm not keen on the fender mount look.
User avatar
doctord23
Supporting Member
Posts: 323
Joined: 01:29 pm Jul 28 2009
Country: USA
Location: NorCal

Re: Hybrid Update

Post by doctord23 »

Yeah, the oversize "f" tank fits pretty well with the rear shroud mount cut off and a little heat applied to squeeze the back side of the tank between the frame rails.

My damper is a GPR with a bolt-on spindle mounted to the frame and the unit on the top clamp.
You can see it in the top picture.
I am thinking of moving it to the 01. For the single track riding that I do, I think that I can live without it. I usually leave it pretty loose anyways.
My Team Green:
2002 KX-KDX 220
2000 KDX 220
2003 KLX 300 DS
1988 White KDX 200C3
1984 KX500 (original owner)
1996 Honda Magna V4
2017 Honda Africa Twin DCT
User avatar
bufftester
Platinum Member
Platinum Member
Posts: 3455
Joined: 06:03 pm Oct 31 2012
Country: USA
Location: University Place, WA

Re: Hybrid Update

Post by bufftester »

Hey SixStringSteve, I tried to answer your question but says you have PMs disabled.
I posted the answer under my hybrid build here http://kdxrider.net/forums/posting.php? ... 1&p=128714
Ffryno13
Member
Posts: 149
Joined: 11:17 pm Nov 10 2015
Country:

Re: Hybrid Update

Post by Ffryno13 »

I m building an 04 rmz250 hybrid right now and I can already guess that the stock 2gal tank isn't going to cut it for what I ride. I was thinking about getting the 2.8ims buy I saw you used an 04kxf tank on your 125 frame so I'm guessing the opposite would also work using a 99-02 125 tank on the rmz250 because they offer bigger sizes and are much less expensive (same bike as the 04-05 kx250f) or am I just crazy?!
Ffryno13
Member
Posts: 149
Joined: 11:17 pm Nov 10 2015
Country:

Re: Hybrid Update

Post by Ffryno13 »

I was wondering if you'd mind sharing some details on your tank swap?
gots_a_sol
Member
Posts: 40
Joined: 10:33 pm Mar 08 2015
Country:
Location: Charles Town, WV

Hybrid Update

Post by gots_a_sol »

Just an FYI, the IMS 2.5 gal kx250f tank does not fit at all without frame modifications. Where they got some of the extra capacity is right where part of the upper shock mount/sub frame tabs are welded to the main frame. Hypothetically if someone were to remove those mounts and weld in new straight ones the tank would fit. :mrgreen:

Also the stock 02 seat won't work either.

Image
-Joe

Husky WR177 - KX125 (200 soon)
gots_a_sol
Member
Posts: 40
Joined: 10:33 pm Mar 08 2015
Country:
Location: Charles Town, WV

Hybrid Update

Post by gots_a_sol »

After way too much effort, here is the full 04/05 kx-f treatment. I need to finish a little bit of welding and make up some tabs for the lower rad shrouds. But it does look so much better now.

I used the tank (IMS 2.5, this caused the most grief), subframe, seat, airbox, and plastics. Total ended up being about $20 more than a new kx ims tank so not bad. Everything was bought used.

Frame needs modded for the IMS tank (a stocker should fit without that) and new tabs welded on for the subframe. The airbox boot is smaller in diameter on the kxf than the kx, so had to stretch it on there quite a bit. Whenever I get around to doing my kdx swap I'll probably stick a lectron on at the same time and order it with a smaller inlet diameter.

Image

Before for reference.

Image
Last edited by gots_a_sol on 02:13 pm Oct 07 2016, edited 1 time in total.
-Joe

Husky WR177 - KX125 (200 soon)
Ffryno13
Member
Posts: 149
Joined: 11:17 pm Nov 10 2015
Country:

Re: Hybrid Update

Post by Ffryno13 »

Nicely done!
User avatar
Tyl3r
Platinum Member
Platinum Member
Posts: 1335
Joined: 06:51 pm Nov 26 2012
Country: USA
Location: SW Pennsylvania

Re: Hybrid Update

Post by Tyl3r »

Yea looks way better for sure! What all did you have to do to the rear shock mount on the frame? Looks like ya moved or modded it. Also, what skid plate are you running? Or is that home-made?
04/05 KX220 Hybrid all decked out
18 KTM 500 EXC-F Dual Sport/Sumo toy
24 KTM 300XC-W Cheater bike
gots_a_sol
Member
Posts: 40
Joined: 10:33 pm Mar 08 2015
Country:
Location: Charles Town, WV

Hybrid Update

Post by gots_a_sol »

The upper supports on the 99-02 go forward up the frame. I chopped them off and welded in new ones with less forward angle to clear the tank. The lower/more substantial mounts are untouched.

The skid plate started out as a Devol I got cheap, but it didn't cover nearly enough so I welded new side pieces on it.

Original skid

Image

Image

Modded skid

Image

Image
-Joe

Husky WR177 - KX125 (200 soon)
User avatar
two-stroke-brit
Supporting Member I
Supporting Member I
Posts: 132
Joined: 05:40 pm Jul 30 2016
Country: USA
Location: HOUSTON TEXAS

Hybrid Update

Post by two-stroke-brit »

i like the skid pan mods.
i am going to making a couple of pans for me and a buddy and will probably end up something like yours :supz:
cheers mark
She might not be pretty but always a fun ride !
Post Reply