Cascadia
Undecided
- Location
- Orem, Utah
An orange poli sport head light right?
KX125/KDX200 Hybrid Build
sixstringsteve
Well-Known Member
- Location
- UT
orange? Yuck. I like white frames with subtle white & colored plastics. I'm not going to pretend it's a KTM (nothing against KTMs).
I'm more interested in getting it running and all fitting more than looks. I'd rather spend money on a steering stabilizer or skid or radiator guards than bling, but that's just me.
I'm more interested in getting it running and all fitting more than looks. I'd rather spend money on a steering stabilizer or skid or radiator guards than bling, but that's just me.
rholbrook
Well-Known Member
- Location
- Kaysville, Ut
Come on Steve. Get going on this thing. I want to ride it. Here is a little encouragement.
[video=youtube;Sk0kC78h-qg]http://www.youtube.com/watch?v=Sk0kC78h-qg[/video]
[video=youtube;Sk0kC78h-qg]http://www.youtube.com/watch?v=Sk0kC78h-qg[/video]
sixstringsteve
Well-Known Member
- Location
- UT
If I did my research correcly, the KDX carb has a 35mm inner bore, and the KX 125 carb has a 36mm inner bore. Unfortunately the outer bore is different, and I don't think the air striker will fit the airbox or reed box on my kdx.
My plans were to have Ron Black mod my KDX carb and head for more low-end and high-end (just like my last hybrid). From his website, his mods include the following:
Boring carb to 36 mm (gives you a better top end)
Installing divider plate (gives that low end response, like a smaller carb)
Modify slide
Install new needle (gives the carb that personality)
Modify jet block (helps with the over all performance)
Modify low speed circuitry (This part of the modification along with the other mods really brings the air mixture screw into play. With only very small adjustments, you can keep your bike running at its peak as you change altitude or with weather changes during your ride.)
But if I can make the air striker carb work on this baby, I will!
sixstringsteve
Well-Known Member
- Location
- UT
Thanks! i've only watched that video about 100 times now.
I'm broke at the moment. I need to sell a few thing so I can find the right KDX200 that hasn't been beat/neglected.
sixstringsteve
Well-Known Member
- Location
- UT
This build has me so excited I'm having a tough time sleeping at night.
- Location
- The Land Northward (Bountiful), Utah
does the 125 run? You should ride it and see if you hate it or not
sixstringsteve
Well-Known Member
- Location
- UT
It does not run. The piston lost a ring and it fell down into the bottom end. I would love to try a kx125 though. I wonder how it would compare to my old kx100. I definitely like the low-end of the kdx200 motor.
I did ride my cr125 a bit before I swapped the motor. It was a light switch. My kx100 had more power down low than the 125. It felt like a 20cc pit bike until it hit the powerband, then it definitely woke up. Nice and light though. THe CR125 felt quite a bit taller (or I've become more comfortable with tall bikes).
I did ride my cr125 a bit before I swapped the motor. It was a light switch. My kx100 had more power down low than the 125. It felt like a 20cc pit bike until it hit the powerband, then it definitely woke up. Nice and light though. THe CR125 felt quite a bit taller (or I've become more comfortable with tall bikes).
Rot Box
Diesel and Dust
- Location
- Smithfield Utah
I'm excited for you. I wish it wasn't such a long drive I'd love to watch it come together. I loved both my KX250 and KDX200--shoulda never sold either of them
sixstringsteve
Well-Known Member
- Location
- UT
I'll make you a deal Andrew. You play tour guide up in your neck of the woods, and I'll play tour guide up AF Canyon. I'd also love for you to teach me how to preperly jet a bike.
Rot Box
Diesel and Dust
- Location
- Smithfield Utah
Deal! We have a lot a trails I think you'd really enjoy. Paradise... Dirtbike Paradise...
I love tuning carbs. I'm a horrible teacher but I will do my best young grasshopper.
sixstringsteve
Well-Known Member
- Location
- UT
Sold one of my mountain bikes today. Now I'm on the hunt for a 1995 or newer kdx200 then the madness can begin.
jentzschman
Well-Known Member
- Location
- Sandy, Utah
Sweet! Looking forward to this build
rholbrook
Well-Known Member
- Location
- Kaysville, Ut
Why not a 220? I am going to look for a 220 for you.
just a crazy idea....what about a 2t WR250 motor? Has the stator, awesome low end torque, very manageable power, and plenty of it. paired with your lighter frame, it would be a pretty rippin' set-up and you wouldn't have to mod it for more zip...I think I noticed one on ksl the other day for like $800. Thinkin' out loud.....
sixstringsteve
Well-Known Member
- Location
- UT
A 220 will work too. I'll take either one, whatever I can find. I'm starting to think a 220 is the way to go. Either way, it needs to be a 95 or newer .
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sixstringsteve
Well-Known Member
- Location
- UT
I like the way you think. That would be a killer combo but I'm not sure it would fit in there. There are all these weird factors to swapping A motor. For instance, the swingarm must be the right width and size to fit the engine cases. And the front sprocket needs to align perfectly with the swingarm. And the head has to clear the bottom of the gas tank. And the head stays have to connect to the frame. And the carb has to mate up to the air box.
Iove the wr250 motor but I'd bet it fits a yz125 better. The kdx200 in a kx125 is a very common swap, so I know exactly what works and what doesn't. 99% of my riding is up AF canyon and the Kdx will be just right for that. Thanks for the suggestion, I didn't mean to shoot it down so fast .
sixstringsteve
Well-Known Member
- Location
- UT
Here's a little info between the kdx 200 and the 220. I'll take whatever I can get with an engine in good shape, but I'm starting to lean towards a 220.
More info here:
http://justkdx.dirtrider.net/200vs220.html
STOCK:
200: If you plan to leave your bike absolutely stock, the 200 is the better all around terrain bike. Nice wide power spread with ample low end power and some upper rpm power available if you want to scream it out. Note that by "scream it", I mean relative to the 220. Compared to a typical 125, both the 200 and the 220 are low rpm torquers.
220: The 220 is a complete torque monster in stock form. It is the king of tight sections, the master of nasty conditions. If you want low end power, this baby has it, and lots of it. Probably an ideal bike for tight, rocky, hilly, terrain. The engine is so strong down low, it can be tough to stall. To pull a wheelie, shift up a gear. The 220 will easily pull a gear higher than the 200 in the same conditions, and probably needs to, as it does not turn nearly the revs as the stock 200.
MODDED:
220 w/ torque pipe, bored carb, Reeds, and aftermarket silencer- Now we're talking a really nice wide-wide powerband! This is my own bike's set up, and I must admit that Ireally like the bike. The powerband begins considerably lower than a 200 w/similar mods, and yet will spin out to about the same top rpm levels as the 200. Although, it may feel like it could turn a few more revs, the powerband is so wide that you can shift early and still easily pull the next gear. Think of this set up as a 200 with a powerband that is twice as wide. This extra powerband width is most appreciated in tight woods sections, but is useful on an MX track as well. Note- Plan on adding the reeds if you bore the carb, or else the engine will lose the wonderful low end, right off idle, snap. However, with the reeds the low end power will be almost the same as with a 33mm carb.
More info here:
http://justkdx.dirtrider.net/200vs220.html
STOCK:
200: If you plan to leave your bike absolutely stock, the 200 is the better all around terrain bike. Nice wide power spread with ample low end power and some upper rpm power available if you want to scream it out. Note that by "scream it", I mean relative to the 220. Compared to a typical 125, both the 200 and the 220 are low rpm torquers.
220: The 220 is a complete torque monster in stock form. It is the king of tight sections, the master of nasty conditions. If you want low end power, this baby has it, and lots of it. Probably an ideal bike for tight, rocky, hilly, terrain. The engine is so strong down low, it can be tough to stall. To pull a wheelie, shift up a gear. The 220 will easily pull a gear higher than the 200 in the same conditions, and probably needs to, as it does not turn nearly the revs as the stock 200.
MODDED:
220 w/ torque pipe, bored carb, Reeds, and aftermarket silencer- Now we're talking a really nice wide-wide powerband! This is my own bike's set up, and I must admit that Ireally like the bike. The powerband begins considerably lower than a 200 w/similar mods, and yet will spin out to about the same top rpm levels as the 200. Although, it may feel like it could turn a few more revs, the powerband is so wide that you can shift early and still easily pull the next gear. Think of this set up as a 200 with a powerband that is twice as wide. This extra powerband width is most appreciated in tight woods sections, but is useful on an MX track as well. Note- Plan on adding the reeds if you bore the carb, or else the engine will lose the wonderful low end, right off idle, snap. However, with the reeds the low end power will be almost the same as with a 33mm carb.
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jentzschman
Well-Known Member
- Location
- Sandy, Utah
6 speed gear box, now that is sexy.
Rot Box
Diesel and Dust
- Location
- Smithfield Utah
Why stop at 220? They made a liquid cooled KDX250 you know... Even a air-cooled KDX450 at one point That is if you could get the massive finned beast to squeeze in there LOL.
Joking aside I don't think you couldn't go wrong with either the 200 or 220
That is if you could get the massive finned beast to squeeze in there LOL. Joking aside I don't think you couldn't go wrong with either the 200 or 220