swingarm

Discussion for swapping a KDX motor in a MX frame...
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ukkdx200
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swingarm

Post by ukkdx200 »

Ive seen a bit of talk about it but has anyone built a hybrid using the kdx swing arm. im no mechanic so what wiuld need to be done to get it to fit and would this affect the shock abd linkage. i.e. would i still be able to use a kx shock?

Never thought i would manage a hybrid but im starting to think.maybe i could do it! im quite happy to use a kx if need be i just like the adjusters and ive already got one!
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KDXohio
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Re: swingarm

Post by KDXohio »

From what I've read it sounds like all you have to do is weld in bushings to the kx frame to accommodate the kdx pivot bolt which is a smaller diameter than the kx pivot bolt.
1990 KDX200 FMF Fatty, Answer VFC silencer, VForce 3 Cage, Wiseco Piston, KX125-J series KYB USD fork conversion, Race tech goldvalves, J series front brake assembly, air-box snorkel removed, Acerbis Headlight, KX450F Front fender, Pro Taper RM bend bars, ASV front Brake lever, MSR Clutch perch and lever, RB Head mod, 36mm PWK carb, Trail Tech Kickstand.
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bufftester
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Re: swingarm

Post by bufftester »

Yes, the KX swingarm pivot is 17mm and the KDX is 15mm. Ideally if you have access to a machine shop you could mill a couple of stepped collars to mount the KDX pivot. User jdmurray started one a couple years ago (http://kdxrider.net/forums/viewtopic.php?f=111&t=9125) but never finished up the build in his thread, you might try contacting him but he hasn't been on in nearly 2 years. If you do a stepped bushing then you wouldn't have to weld anything to the pivot area, drill the case, or cut a swingarm. On the other hand KX swingarms are cheap on Ebay (at least here in the states).
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KDXohio
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Re: swingarm

Post by KDXohio »

It also allows you to put the engine back into a kdx chassis if ever needed
1990 KDX200 FMF Fatty, Answer VFC silencer, VForce 3 Cage, Wiseco Piston, KX125-J series KYB USD fork conversion, Race tech goldvalves, J series front brake assembly, air-box snorkel removed, Acerbis Headlight, KX450F Front fender, Pro Taper RM bend bars, ASV front Brake lever, MSR Clutch perch and lever, RB Head mod, 36mm PWK carb, Trail Tech Kickstand.
ukkdx200
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swingarm

Post by ukkdx200 »

thanks for your answers, having thought about it a bit more if I do go for a hybrid I will go the tried and tested route of a kx swinger

im really struggling with weather to do a hybrid or not, I want one theres no doubt about that but prices are that little bit more in the uk compared to the us, it would be far easier for me to sell the kdx and spend maybe £300 - £400 more and get something like a gas gas 200 or 250 which would easily have me a nice bike with better suspension however it wouldn't be a Kawasaki! at the moment I think my plan is going to start sourcing parts slowly and cheaply in no rush, Ive managed to pick up an oversized tank for well under $20 including delievery from ebay so if I can take my time and get all parts cheaply that could be a way, I want to go for a 2003 model onwards engine is a 98H model Im lucky that the bike already has a decent front end set up so that at least should be a straight bolt on swap

I think ive just talked myself into the kwaker! really fancy having something unique
KarlP
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Re: swingarm

Post by KarlP »

To me, the whole point of of the hybrid was to put a good motor (KDX) in a fast chassis, in my case I used a CR250. I could have bought a good used CR250 for less than it took to put the hybrid together, but wheres the fun in that?
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bufftester
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Re: swingarm

Post by bufftester »

True, I could have found another KDX, and done a front end swap on it, and still came out cheaper than doing a hybrid, but some of us are just twisted in the head :roll: and besides, I really hate orange and red. Of course, my bike does rip, is one of a kind, and I can say I built it myself
ukkdx200
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Re: swingarm

Post by ukkdx200 »

bufftester wrote:True, I could have found another KDX, and done a front end swap on it, and still came out cheaper than doing a hybrid, but some of us are just twisted in the head :roll: and besides, I really hate orange and red. Of course, my bike does rip, is one of a kind, and I can say I built it myself
I really fancy the one of a kind thing. I've looked at other bikes but they just dont excite me like a hybrid does. I'm not in a huge rush as money is really tight at the mo so I'm going to start saving and aquiring some parts and keep an eye out for a donnor bike. I missed a perfect one the other week on ebay. £300 for everything of a kx125 2003 missing engine and tank but everything else was there so thats the sort of thing I'm after
I'm quite nervous that I havent got the mechanical skills to do it but surely theres only one way to learn and that's to do it!
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bufftester
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Re: swingarm

Post by bufftester »

Mechanically it isn't that hard. The hardest bit is the engine mounts, and that is just because most of us think of welding as magic (at least I did lol). Besides drilling the case out to 17mm (any machine shop can do it for you), and cutting the swingarm (an angle grinder is perfect but a hacksaw gets the same results) the engine mounts are the only really big issue. It was enough of an excuse for me to buy a wire-feed welder and practice on scraps, and it has held up well the first year with lots of use. I didn't rush through my build, took about 4 months just tinkering on the odd saturday between work. Plus it makes for great stress relief to just disappear in the shop for a few hours to tinker :grin:
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