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heres a thing i been wanting to build since i was a kid.....Its a KX100 92 model that i bought some time ago that im converting into a trike.

For those that dont know about these (motocross trikes) the silly things go against the laws of physics with there live chain driven rear axle,non IRS rear end and overpowered engines.They were started by

honda in the early eighties in the form of an ATC250r.First version was powered by a honda CR250 air cooled motocross bike engine and as nomal someone asked "can we race these?" well sure as poo

the americans started racing them.Other manufactures jumped on board and kawasaki manufactured the KXT250 with a Kx250 engine.In the mid eighties they started to get as advanced as the motocross bikes with front and rear disc's and a higher powered CR250 and KX250 water cooled engines....kawasaki had there powervalved engines for even more grunt throughout the rev range.Yamaha also go on the ambulance ride to the hospital and produced the YTZ250 tri-z......Im fortunate enough to have all three of the last models of all the above stashed away in the loft....they really are a fun thing to ride....or drive...or fight the laws of physics on.....The american govenrment banned the manfacture/sales on these things which wasd a shame as the japanese had put some money in developing these things....maybe to much???As they were built for the american market I see it as a case of "you wanted it.......here it is.....GOODLUCK!!!"Well they may be able to place laws to "protect the people" from doing there selves harm on these silly contraptions by placing a ban on big companys making and marketing these things....but they cant take away our desire and ability to modify things......this is going to be sick as :)So i bought one of the higher qaulity chinese quad bikes for the rear end/wheels and front brakes

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here ive set up the standard swingarm in my chassis jig,its a global jig motojig,its for bending motorbike frames back into shape after youve had a stack,you can also build in it

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here i have put the scheibner laser geometry machine on to measure all the referance points of interest,namely the space where the engine fits,the centre or the rear tyre and the offset of the rear sprocket...you can see the laser measuring dot on these points.

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then ive set up the fixtures for the suspension linkage mount....now i have the bench set up with the centres of the swingarm pivot to centre of rear axle and the linkage mount point all mechanically and the laser measurements for all the other points of interest in the computer im ready to take the arm out and adjust the bench to take the track of the wide rear axle.....and im ready to build....ive cut out the rear carrier off the chinese swing arm and made the rest of the swingarm to the kawasaki specs........heres the unit still needing some braces in the rear half and the suspension linkage mount

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hahaha lad you like it..... nah still waiting for the body to come back from the blaster....he is pretty busy,when its done its done...i dont mind it just gives me more time to accumulate more new parts :)....anyway....pretty much finished the swingarm....about 6 hours all up,pretty happy still need to make the suspension linkage and weld it on and fit the bearings and bushes but i trial fitted to get an eye ball on it.....with out the swingarm linkages on it hangs down but you get the idea of how its gunna look.

I dug out a new old stock rear fender for my KXT250 trike and sat it on and i think i can adapt it to fit(ofcourse i will be using the second hand one off the 250 trike as i will be using the new stuff on the 250......one day i will restore it :) )

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i should get the bearings/bushes/seals any day now then i will finish off the arm with paint and factory "uni-track" decals for the factory made look then i can fit it all in and put the wheels on,set the ride height up and work out the rake i will be using......i plan to make a set of billet triple clamps (wider than standard to fit a wide quad bike wheel in it) with rake built into them(the headstem shaft hole is bored on a different angle to the frames geometry).....what this does is changes not only the rake but the scrub radius so sitting stationary the bikes(or now trike!) handlebars should want to fall left or right.....but when moving it will want to track straight.Then for example when turning right(to turn these things you must slide them) the bars will automatically counter steer to the left.I will be doing the CAD for these in the next few days and making them in the machine centre possibly on the weekend.

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I hope your health insurance is current.

No worries ;) I raced an atc250r when i was 16 (i dont know how i didnt end up killing myself on it looking back)I have good experience on trikes but having said that they can turn bad on you at anytime and they bite hard!

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  • 1 month later...

havent had time to update but heres where its at...finished swingarm,epoxy primed,painted fitted and made the tool die to hot brand the seat (its really for my kxt250 resto but i will use it on this aswell to make it look authentic)Test drove the tool die,works great just need to fine tune the heat/stamp time...i tested it on foam backed vinyl so the die bottomed out and left a border,this shouldnt happen on the proper material as its not foam backed

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