A path less travelled 97 kx125

[KDXGarage]

Nice! Looks great.

[John_S]

Congratulations on all the hard work paying off. I give you a lot of credit for taking a tough path and sticking it out. Those 70 number plates remind me of Ricky Carmichaels 1998 Splitfire KX 125. I remember that was the first time I saw a KX with black wheels and loved that bike.

Screenshot 2023-07-10 135146.png (1.12 MiB) Viewed 3423 times

[Ridea200]

Already typed this once, so here's the short version...
Sub-mount steering damper:
97 kx250 top triple clamp (holes ovaled out toward inside about 1mm for the 450 mount)
Brp Sub-mount for 09ish kx450f
Brp bolt on tower for 97 kx125 (trimmed to fit Sub-mounting)
Scotts damper
With all the above parts (and the mentioned mods) all that was needed was to use a spare top clamp washer to space the top clamp up, so the damper didn't bottom out on the stem.

[Ridea200]

My footpegs had seen better days, but didn't want to go with the ims pegs. After looking up what others had done, I picked up a set for a ktm. They're moose brand, have a curve to them, front to back, and are set back .25". Also, just plain bigger than stock. I used the stock pin, and spring, but had to drill a hole in the peg to capture the spring. Also, the pad area, that hits the frame, was shaved down a little so they sat at 90 degrees. The end of the peg was up/back just a little. Nothing crazy though. To top it off, I shaved down the area of the peg that hits the rear brake lever, so that its flat on the lever, and not a corner. I think a lot of that part has to do with the setback...

[KDXGarage]

Nice!

[Chuck78]

So what's the feeback on the finished product compared to a KDX chassis?
I'm considering a future project for my spare 220R engine still... A SmartCarb SC2 36 would be a very nice addition, but your carb clearance issues with the tiny PWK carbs has me wondering if a SmartCarb SC2 36 would even fit WITH frame mods. More photos of your carb mounting versus the frame would be very helpful.

I'm also curious as to the feel of the KX125 hybrid vs a 95+ KDX, particularly a KDX upgraded suspension. I'm really wondering less top heavy as a KDX. That is the big motivating factor that would make me build a hybrid vs just sitting on my spare 220 engine and being content owning 97 and '99 complete 220 bikes and perpetually modifying them.

[Ridea200]

Chuck78: I'll try to get some better pics, and measurements for you. Keep in mind, this is a 97 kx chassis, so newer ones, as far as I know, don't have the same issue with carb fitment. Also, I could have made more room, but didn't need to...That, and this is a 200. Is the 220 cylinder bigger around?
As far as handling, and such...I've been messing with sag/clicker settings a little, as they needed attention anyway. (Ill post full set-up later.) Now, it handles like I want... I mainly ride woods/desert. From what I remember, the kdx chassis was pretty good. Comfy, and stable. Not really a race bike though.
What are your plans? I would say, at this point, if you have a spare engine, do the swap. Race bike or not. I can putt with the fam, then just go race mode. This is what the kdx should have been sirca 00...

[Chuck78]

As far as handling..., it handles like I want... I mainly ride woods/desert. From what I remember, the kdx chassis was pretty good. Comfy, and stable. Not really a race bike though.

This is what the kdx should have been sirca 00...

You are very correct about that last bit especially... Too bad Kawasaki let KTM begin surpassing them in 1998 & never tried to get a foothold ever again in woods / enduro bikes. Until the last year or 3 as Kawi really began taking serious note of how popular woods / enduro racing and wiids riding has become, which is primarily dominated by European 2-strokes since the new millennium!
I'm crossing my fingers that the 300cc fuel injected 2-stroje they've been developing for a KXF chassis will be called the KDX300R for the 2024 or 2025 model year...

I'm currently gearing up for several massive winter projects, including rebuilding my '99 KDX220R with 98 RM125 forks and '01-'04 RM125 shock, and a big chunk of $$$$ in titanium parts to try and get it closer to the weight of a KTM 200 etc.

I was still very intrigued by the thought of picking up a 1996 or 2005 KX125 basket case. I've more recently learned of KX151 & KX167 engines from a big bore engine builder named Rick Petersen I believe, MAX RPM I believe is the shop name. 100 octane suggested fuel on a bored ported stroked cylinder with clearanced crankcase and re-chambered head... Wow. This sounds pretty appealing except for the $2000 price tag as they don't sell kits, they build big bore engines. The 167cc especially sounds appealing as I love the lugability of my grunty 220 far more than the lesser lugability of a KDX200H even with maximum ignition advance and a Gnarly Woods pipe... So as a trade off for weight savings and sticking with a 125 engine base, the biggest big bore stroker possible would be the goal. Perhaps it could be focused on low rpm torque porting. This would make for a really interesting build.

For now, I'm focusing on rebuilding my old KDX 220 with as much in the way of titanium parts weight savings as I can, including cylinder studs from Titan classics, brake caliper pistons and full brake hardware kits, kx500 titanium swing arm pivot bolt and suspension linkage bolts, axles, etc in order to keep the short wheelbase / steep steering angle KDX chassis, has it really does quite well. I've seen one project where a guy used a KX 125 aluminum rear subframe on a KDX E-Series. Was intriguing but I'm not sure if I would go that hardcore just to save another pound or two, at the expense of durability. Tossing the bike on its side doing rugged gnarly woods riding, the rear fender and side covers really take a beating at times. That would be an interesting project though if I learned how to TIG weld aluminum, in order to add the proper tabs and bracketry to keep KDX plastics on it.

[Ridea200]

Chuck78: No new pics, but I just looked at the carb/frame clearance again. Its probably 2-3mm. It wouldn't be hard to get more if needed though. Also, I saw in another post, that you where talking about seats. Mine is shaved to fit an 06 kxf cover. Although not as comfy as the kdx, its about as good as it gets for an mx bike. No discomfort on long rides.
As far as picking the bike up: Even though its obviously heavier than the "125", its not to bad. Other than hill climbing, I haven't crashed to much though/had to pick it up tired.
Now if I could swap in a bunch of titanium like what your planing/doing on your kdx, that would be sweet. Even with my light, damper, and big tank (and getting the suspension way more dialed) this thing doesn't feel heavy. I ride woods/desert, and have had no issues/concerns.
I haven't ridden a 220, but I don't have any lugging problems.
Never have...13/47 or current 13/50...
If you where closer, I would let you go for a rip...