Hybrid Gene Splicing

Discussion for swapping a KDX motor in a MX frame...
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Tedh98
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Re: Hybrid Gene Splicing

Post by Tedh98 »

Did the carb ring not work out?
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Tyl3r
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Re: Hybrid Gene Splicing

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Well, I was trying to get around having a new one made. I'm done trying, going to measure again and have a new one made. I tried this lip adapter yesterday and didn't have much success. The angle of the carb and the boot aren't the same, when I tightened the clamp down, it kept squishing out the rubber lip at the top. I tried all kinds of different ways to make it work, just wasn't having it. I need to have a new ring machined to press onto the carb. When I do, I think I am going to need to have a lip on it, just like the carb normally has, to help keep the boot on. The first ring I had made did not have a lip on it, both bores were smooth. I'll post some pics and more info in my build thread when I get some time and finish the carb ring design.
04/05 KX220 Hybrid all decked out
18 KTM 500 EXC-F Dual Sport/Sumo toy
24 KTM 300XC-W Cheater bike
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bufftester
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Re: Hybrid Gene Splicing

Post by bufftester »

A few seasons of hard riding and everything is still working well. My carb adapter using the boot lips has never failed and never given me an issue. This includes lots of seat depth creek crossings, lots of DUSTY desert riding, and normal maintenance. This year I'm going to try some bar risers to get the bars forward and up a bit to make standing a bit more comfortable, the stock KX250 clamps just seem to pull back too far. Also need to trim a bit off my steering stops. The KX frame turn radius is a bit larger than the KDX, so trimming the stops and moving the forks up about 5 mm in the clamps should be the ticket for our tight woods riding. She'll get a new top end after this season, and probably some RB work while it is apart. Any questions I have a ton more pics in the gallery that I didn't include here.
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Tyl3r
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Re: Hybrid Gene Splicing

Post by Tyl3r »

Any way to get the pics working in this thread again?
04/05 KX220 Hybrid all decked out
18 KTM 500 EXC-F Dual Sport/Sumo toy
24 KTM 300XC-W Cheater bike
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Chuck78
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Re: Hybrid Gene Splicing

Post by Chuck78 »

I was hoping for the same, a few photos of a 99-02 build, as well as hoping to hear if any pipe mods are needed to fit the KDX FMF pipes or Pro Circuit pipe onto a 99-02 hybrid. Most of the builds that I looked at over the weekend were 2003+ KX125 chassis. I'd like to run a 99-02 for many reasons. If there were more aftermarket support for guards/armor, radiators, etc and better clearance for a SmartCarb SC2 36, I'd go with a purple '96 (94-98 ggeneration) 125 hands down...

The pipe fitment is one concern, I like to be able to interchange parts between my two 220's amd potentially the new 125 chassis home for my spare 220 engine, but also, on the 99-02, the side plastics number plates appear to have a hand hold built into them. Is this the case, and is the subframe rail directly under there to grab? Or are you just grabbing the seat base? I really like that feature on the KDX, & the 95-98 appear the same as the KDX with built-in hand holds.

I'm looking to try and shed more weight up high, and although it's still a perimeter frame and corresponding fuel tank design, and a 3.0g or 3.4g desert tank will in fact add part of the KDX's top heavy feel back onto the KX chassis, I see a few areas where the center of gravity is lower tank placement is slightly lower perhaps???), and weight savings are implemented (aluminum seat subframe and slimmer seat thickness).

Let me know especially about KDX pipe mods to fot a 99-02 with KX250 spark arrestor, and the head holds on 99-02 side panels.

Thanks!
'97 KDX220R - purple/green! - KLX forks, Lectron, FMF, Tubliss
'99 KDX220R project - '98/'01 RM125 suspension, Titanium hardware, Lectron Billetron Pro, Tubliss
'77 Suzuki PE250 & '83 Suzuki PE175 Full Floater - restomod projects
'77 Suzuki GS750-844cc, '77 GS400/489cc & '77 GS550/740cc projects
'62 GMC 1000 Panel Truck
'88 Suzuki Samurai TDI/Toyota swaps
'88 Toyota 4x4 pickup
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bufftester
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Re: Hybrid Gene Splicing

Post by bufftester »

Chuck78 wrote: 12:34 pm Oct 23 2023 I was hoping for the same, a few photos of a 99-02 build, as well as hoping to hear if any pipe mods are needed to fit the KDX FMF pipes or Pro Circuit pipe onto a 99-02 hybrid. Most of the builds that I looked at over the weekend were 2003+ KX125 chassis. I'd like to run a 99-02 for many reasons. If there were more aftermarket support for guards/armor, radiators, etc and better clearance for a SmartCarb SC2 36, I'd go with a purple '96 (94-98 ggeneration) 125 hands down...

The pipe fitment is one concern, I like to be able to interchange parts between my two 220's amd potentially the new 125 chassis home for my spare 220 engine, but also, on the 99-02, the side plastics number plates appear to have a hand hold built into them. Is this the case, and is the subframe rail directly under there to grab? Or are you just grabbing the seat base? I really like that feature on the KDX, & the 95-98 appear the same as the KDX with built-in hand holds.

I'm looking to try and shed more weight up high, and although it's still a perimeter frame and corresponding fuel tank design, and a 3.0g or 3.4g desert tank will in fact add part of the KDX's top heavy feel back onto the KX chassis, I see a few areas where the center of gravity is lower tank placement is slightly lower perhaps???), and weight savings are implemented (aluminum seat subframe and slimmer seat thickness).

Let me know especially about KDX pipe mods to fot a 99-02 with KX250 spark arrestor, and the head holds on 99-02 side panels.

Thanks!
First the pipe fitment. I used the stock KDX pipe and my aftermarket FMF silencer (also for a KDX) and had no issues fitting it. You make it much easier for yourself to get the pipe fitment mocked up before you make your engine mounts as just a couple mm in either direction is the difference between the pipe clearing the down tube or not. You do have to fab a little bracket for the silencer to mount to the frame, I actually used the stock KDX aft motor mount plates as I had to cut the aft motor mount off the head for proper fitment in the frame. All the other pipe mounts are the stock KDX ones attached to the KX frame.

All the subframes on the 2000+ frames are aluminum. There are handholds of a sort on the KX plastics, but I have a tugger strap installed on my seat and forks so I ususally use those.

If I were to do it over again, I'd start with a KX/RM 125 or 250 frame from 05-06. Steel frames, geometry still basically the same, and lots more aftermarket support still. You can still even get a bolt on kickstand that fits those years.

I'll see if I can edit my posts in this thread to get the photos back live.
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Chuck78
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Re: Hybrid Gene Splicing

Post by Chuck78 »

Thanks!
I noticed the geometry was a lot different on the '03-'05 KX, 26° to 27.5° head angle, and nearly a 58" wheelbase vs 56.5". That is what led me to favor the '99-'02, as well as having a ton of aftermarket support vs almost none on the 94-98. Far more aftermarket fuel tank offerings and less 1-2 year only parts on the 99-02 vs 03-05. The RM those years have incredible suspension, especially 05-08 RM125 & 250. The 01-04 RM125 suspension is still very similar Showa Twin Chamber as with the 05-08 RM125/250 revisions, while the 01-04 RM250 used KYB.
I have a thing for keeping it green though, despite my love for Suzuki motorcycles and 1996-2008 RM & 1991-1998 RMX250 suspensions.
'97 KDX220R - purple/green! - KLX forks, Lectron, FMF, Tubliss
'99 KDX220R project - '98/'01 RM125 suspension, Titanium hardware, Lectron Billetron Pro, Tubliss
'77 Suzuki PE250 & '83 Suzuki PE175 Full Floater - restomod projects
'77 Suzuki GS750-844cc, '77 GS400/489cc & '77 GS550/740cc projects
'62 GMC 1000 Panel Truck
'88 Suzuki Samurai TDI/Toyota swaps
'88 Toyota 4x4 pickup
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