My new project, turning a vintage 1974 Kawasaki mc1m 90 cc minicycle in to a fun trail bike and a fast vintage mini racer.
Started with two of these, bought them from the same guy on craigs list really cheap and going to get one going with a lot of motor mod's and some better suspension mod's. like the stock wimpy front fork was replaced with a better xr80 fork. had to machine a new steerer tube and put newer tapered head set bearings at the same time and fabricate a new seal. then got some longer all aluminum bodied Chinese rear shocks to level it back out. they seem to be okay for the price!
I had to clean out rust in the tank. took off the oil injector and plug all the holes remaining up, had to rebuild the carb, new points and condenser,new rings,all new out side oil seals and o-rings.
I replaced the stock rubber foot pegs with more modern spring loaded kx85 foot pegs, with some grinding and drilling. made a hinged shift lever fit. new brake pads. I took the stock air box off and put a plastic tube up under the new side #plate with a new uni-filter on it.
The stock chrome handlebars were good so I just replace the levers,throttle,kill button,grips and cables. put new tires on but could not find the original size for the rear, so I installed a newer bigger 3.50 tire which changed my gearing so I installed a larger rear sprocket.
Next will be the motor mods since its kind of slow! but these kawasaki 90/100cc rotary valve motors are all the same, which means the green streak stuff will fit! green streak/centurion 100's had 18.5hp stock! and these little 90's were 6.5hp stock for beginners.
All you do is put a ported aluminum center port 100 cylinder on, cut rotary valve, bigger carb and a expansion chamber, and all just like the green streak specs and it will be wheeling pretty easy!
But I will need frame mods to fit the center port 100cc cylinder. every thing else I have, including a old Hooker pipe which are hard to find!
We,ll leave the other Kawasaki 90 kind of stock until we see how this one turns out?
Pictures here are of the way the stock suspension looked compared to the modified.
Next I,ll show pictures of the motor when I start in to it tomorrow. we have a few extra Kawasaki 100/90cc motors and we might stick one in to either my Rupp or another frame?
Started with two of these, bought them from the same guy on craigs list really cheap and going to get one going with a lot of motor mod's and some better suspension mod's. like the stock wimpy front fork was replaced with a better xr80 fork. had to machine a new steerer tube and put newer tapered head set bearings at the same time and fabricate a new seal. then got some longer all aluminum bodied Chinese rear shocks to level it back out. they seem to be okay for the price!
I had to clean out rust in the tank. took off the oil injector and plug all the holes remaining up, had to rebuild the carb, new points and condenser,new rings,all new out side oil seals and o-rings.
I replaced the stock rubber foot pegs with more modern spring loaded kx85 foot pegs, with some grinding and drilling. made a hinged shift lever fit. new brake pads. I took the stock air box off and put a plastic tube up under the new side #plate with a new uni-filter on it.
The stock chrome handlebars were good so I just replace the levers,throttle,kill button,grips and cables. put new tires on but could not find the original size for the rear, so I installed a newer bigger 3.50 tire which changed my gearing so I installed a larger rear sprocket.
Next will be the motor mods since its kind of slow! but these kawasaki 90/100cc rotary valve motors are all the same, which means the green streak stuff will fit! green streak/centurion 100's had 18.5hp stock! and these little 90's were 6.5hp stock for beginners.
All you do is put a ported aluminum center port 100 cylinder on, cut rotary valve, bigger carb and a expansion chamber, and all just like the green streak specs and it will be wheeling pretty easy!
But I will need frame mods to fit the center port 100cc cylinder. every thing else I have, including a old Hooker pipe which are hard to find!
We,ll leave the other Kawasaki 90 kind of stock until we see how this one turns out?
Pictures here are of the way the stock suspension looked compared to the modified.
Next I,ll show pictures of the motor when I start in to it tomorrow. we have a few extra Kawasaki 100/90cc motors and we might stick one in to either my Rupp or another frame?
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