Franken-Fighter (kinda pic heavy)

[tundrazach]

This is my first mini bike build. The goal is to build this bike to look like a mini street fighter, and to be as cheap as possible.

Bought "gem" this of craigslist for $10. The ad had no pic, but for 10 bucks i figured what the heck. Pretty much complete rolling frame, a motor that the clutch blew out and cracked the case in half, and the top monocoque type bodywork.

This is after I pulled the useless little 49cc motor out. Next to a golfcart for size comparison. Pretty large sized pocket bike, which is great considering im like 6'1" haha. Got some mean looking wide tires on it too

After digging around in the shop at school, i was able to piece together a flathead briggs motor. I dont know what model it is at all, but it appears to be in great shape with little use. Its got some crazy long milled aluminum adapter that fits a tillotson bowl-less carb with a custom made velocity stack(for lack of a better word) on the intake of the carb. Then I found a coil that fit the bolt spacing on the block and the radius of one of several flywheels I found in a box. Topped it off with a starter cup and I had the little beast running

Did the following tonight:

This pic shows the motor in the frame after cutting out the battery box and original engine mounts, and then welding in the new engine mounts. I also started making the exhaust pipe.

Exhaust finished

(not so much pic heavy right now, but will be as project progresses)

 

[tundrazach]

and this shows both of my projects.

The golfcart is nicknamed Berserk-Cart. Its got a 700cc V4 in it. Its nearly drivable, just have to finish a few small parts

 

[ramairgtz]

You beat me to it! I have an x7 rolling frame and a 5hp briggs that are going to go together some day. Looks good so far keep us updated with pics!

 

[tundrazach]

You beat me to it! I have an x7 rolling frame and a 5hp briggs that are going to go together some day. Looks good so far keep us updated with pics!

the trickiest part is flipping the drive from the factory right side to the left side. I had to weld the one way gear on the rear wheel shut, flip the swingarm pivot, and am having to make new idlers for the swingarm pivot since im going from the factory (size???) chain to a #35. Ive got a worked over 5hp tech on a crappy yardcart that I may put in this frame later.

So this bike is an x7? I got no info on it when I bought it

 

[ramairgtz]

Yours looks like a cat eye bike on my x7 the drive is already on the left side

 

[devino246]

Great find for only $10. Certainly looks like you know what your doing.

 

[r97]

the trickiest part is flipping the drive from the factory right side to the left side. I had to weld the one way gear on the rear wheel shut, flip the swingarm pivot, and am having to make new idlers for the swingarm pivot since im going from the factory (size???) chain to a #35. Ive got a worked over 5hp tech on a crappy yardcart that I may put in this frame later.

So this bike is an x7? I got no info on it when I bought it

i believe most pocket bikes come with either #25 or #25h (heavy duty) chain. i hate to tell you but did you ever think of installing a jack shaft (i'm assuming flipping the wheel around wouldn't work for some reason)

yea 10 bucks is a great deal!

p.s. zach, isn't your engine spinning the wrong way, or do you have a gear box or is the engine just weird?

 

[tundrazach]

Im positive the bike is(was) a cateye bike. Eh, now I am glad it didnt come with all the plastic bodywork, cause those headlights are really odd haha

i believe most pocket bikes come with either #25 or #25h (heavy duty) chain. i hate to tell you but did you ever think of installing a jack shaft (i'm assuming flipping the wheel around wouldn't work for some reason)

yea 10 bucks is a great deal!

p.s. zach, isn't your engine spinning the wrong way, or do you have a gear box or is the engine just weird?

Flipping the wheel will work now because the one-way sprocket bearing on the wheel is now welded together. Now it acts as a sprocket mount.

I dont know what the actual size of the #25 or 25h chains are, but most sellers of the cateye say its an 8mm chain. I can tell you that it is smaller than a #35 chain though.

No, this engine spins just like a gokart engine. I have a centrifugal clutch on the other side of it that you cant see. the factory weedeater motor used a transmission to reduce the gearing and reverse the rotation, which allowed for the right side drive. I had thought about making a similar device out of a junk motorcycle transmission to look real industrial/mechanical, but then i remembered the great rule of thumb K.I.S.S.

I had thought about a jackshaft, but this way just seemed easier. Once I get my hands on some 660 bronze, I can make a bushing for my gearing reducer sortof jackshaft (two different tooth sprockets welded together) thing and hook up fuel and throttle cable and it should be ridable once i tune the carb.

Im going to be at Road Atlanta for Petit LeMans all weekend, but I should have some new pics next week

 

[tundrazach]

oh, and those of you that like those "whats different between these two pictures" games, heres a hint. Theres something installed in the bike in the second pic that is not in any of the other pictures. Its a sweet peice, that will be a nice little centerpiece of the project when completed