50+MPH is possible

[MRFIXIT]

I have a 1986 spree, been tinkering with it for 13 years! Start by changing cases to a late 90's elite, this gets you a variator, a 3.5 rear tire will fit on this case. Next split the case and smooth out every rough spot and obstruction this goes for the intake too, don't go overboard bigger is not better. Mine has a tillotson 14 mm carb off a concrete saw and a small K&N filter. Exhaust is a tuned pipe using the stock head pipe 10 inches long with a expansion chamber off of a yz 60 dirt bike. Smooth every port in the cylinder, the best piston head clearance is .020, modeling clay is a good way to check this. This combination with a little tinkering has gotten me up to 52 MPH.

[noiseguy]

Good info. Did you use an Elite engine, or just the cases? Which crank did you use? Stock reeds? More info please!

[Shane4188]

You could make a small business out of this. I live in lexington, louisville is not too far off. I may come down. lol

[MRFIXIT]

Use the complete engine, the jug is different, crank different, piston is the same, head is the same, all wiring is a plug in, the rear wheel is different from a spree. You will need a welder, use the spree motor mount and the elite, cut both in half and use the frame end of the spree and the motor end of the elite. Use the elite shock move shock mount rearward on spree frame. Stock reeds I haven't seen any advantage in carbon reeds other than when they break they don't tear up anything

[MRFIXIT]

forgot to say mine is still a 50cc, take front forks apart and cut 1/2 inch off springs, take off floorboard and all wiring, cables ect. heat frame, lightly!! bend back 3 degrees to add more rake for more stability. The elite rear shock is a hydrualic unit a big help in itself. Also when you do the motor swap it puts the rear tire almost rubbing the rear fender, about 2 inches more wheelbase, helps stability.

[Tippmann98]

haha, nice. Very cool idea. I wouldnt have thought of going with a smaller carberator.

[Spreed]

Great advice! someone should document this swap and put it in the tech or performance section!