85 Tecate Plus One KX500 Motor

[BigGreenMachine]

Looking to make the swap before Christmas comes. I know the lower frame rails need to be changed as does the downtube but its fully within my limits to do so. What else needs to be changed to fit this motor? I assume the rear swingarm/motor mounts line up and fit just like the 86/87 Tecate/KX500?

In any case look for this swap to take place as well as a no link rear suspension swap.
James

[moose 53]

I did a swap of a KX500 to a 85 Tecate a few years ago .You have to mod the frame ,if you have the dirt bike frame just cut out the part you need and weld it to the Tecate frame .I also had to cut the the 500 pipe so it would come out on the same side that the Tecate pipe did. Take your time and you shouldn`t have any big problems.

[3Razors]

I would run with the 89 and later motors. They have better transmissions and more parts available.

[BigGreenMachine]

Thanks fellas, thats some solid info right there!

Are all KX from 89 and up the same motor?

[BigGreenMachine]

Its funny, to say that this is a hard swap isn't really true. Swap frame rails and part of the downtube and the rest is cake aside from making the expansion chamber line up. Reinforce the frame itself and use slugs at the joins between the KX and KXT frame..oh my...now the hunt for a good motor and used frame begins.

James

[3Razors]

Yes the 89-04 motors are identical. It is a super easy easy swap. Cant really get any easier in my mind. Use the 500 pipe, making it fit in a tecate will probably be the hardest part of the conversion, unless you run with a side pipe. Build it strong because the kx motor will try and break mounts, ect. To minimize the vibration put a "bar snake" in the handle bars and use foam street bike grips. If your lucky you can find a donor KX500 for cheap. That way you will get all the other components so it wont nickle and dime you. Keep us posted cause I want to see it evolve!!

[BigGreenMachine]

What about cooling? Will the stock tecate rad cover it or should I mount up the KX rads somehow?

[BigGreenMachine]

For anyone interested the Tecate radiator will cool the big 500. On that note it'll be wise to run engine ice coolant as a precaution.

James

[scooterroo]

big green, cant wait to see this thing take shape. you using an 84-85 model or the 86-87 model as your base to start off? is this something your doing to your current ride or are you getting another one to start fresh with?

[BigGreenMachine]

Using my current 85 frame and modding/making the engine cradle fit the 89-04 KX motor. Will have the funds to buy parts in two weeks.

Big, BIG thanks to Moose53 for letting me pick his brain about the swap and having the patience to put up with a young'in like me.

l8r

[BigGreenMachine]

Have an 88 KX500 motor paid for including all electronics and misc pieces I need. Still looking for a pipe. Will be building the cradle and I've decided I'll build a +6 swingarm out of steel rectangular tubing. Whats a good wall thickness swingarm building?

Should motor mounts be made from steel? What thickness?

[BigGreenMachine]

My motor sitting in its old home.

[hadar]

What are you going to do about the pipe? Are you going with a custom pipe or do you have somthing in mind that will fit with a few mods? Sounds like she could turn out to be pritty mean.I got an 88 kx250 and it's power band is sweet, I love that bike. I can only imagine the kx500 I'm sure she will produce big bore horse power in a trike.

[BigGreenMachine]

I plan on buying the stock pipe and reworking it to fit.

Anyone have some good airbox ideas?

[BigGreenMachine]

Heres where I am. Stripped trike that is waiting on the 500 motor. Motor should be here by the end of the month. PLan is to mount the motor, mod the pipe then work on the extended swingarm and no link rear suspension. LOTS TO BE DONE!!