Treassures in another mans trash

i had used the china girl/happy time for a few previous builds and had a lot of fun doing it. then it changed, everything started from the bulk trash collection in my city. down the street a neighbor was tossing out a lawn mower and few streets over another lawn mower. this is the point where everything changed. i started looking up what can be done with briggs and stratton vertical shaft.

later on when i was looking for parts at the metal recycle yard. thats when i found a honda gx200 the only thing missing from it was a carb. after a few more visits produced subaru ex21 and ex17, another gx200.

i had not visited the yard for some time, working on the motors, breaking them down and rebuilding them, so i had a feeling to go back after months. and found most of a gx160 that was still salvageable.

there is a lot of info on these hondas, but i wanted to document that using gx160 parts on a gx200 will be a cheap way to get more performance.

so i guess what i am trying to say is that i would like to thank all the people that dont take care of their small motors and have contributed to my cheap build of motorized bicycles and light motorcycles.

ill have pics a little later of what i have done with what i have found.

cleaned out gx200 from the recycle yard

gx160 head 18cc

i used a briggs and stratton pull start cage because it was slimmer than the honda.

i also wont need a flywheel key for timing because the gx160 flywheel has a factory advance of 4 degrees.

so pretty much a street setup for my found gx200 has cost me just over twenty bucks.

gx200 motor degovn , gx160 18cc head flat top piston and flywheel, emulsion tube from a 4.5 tecumseh, and knocked out 18 of the fins on the fan, later i will get a airfilter kit with choke holder and throttle kit for the carb. springs and cam and all other little goodies for later.

buba said:

careful Gallo---

I know from experience- those scrap yard runs can be addicting and will ALWAYS yield
SOMETHING... enough to fill your house your backyard your garage and driveway until you just can not find or dig out that which you know is there!!!!

but it is fun....

Click to expand...

Buba the wife has already told me to do something with what i have and no more until they have a home somewhere else. but will keep a small collection just for the interchangeable parts that i find. tomorrow i should have some simple frame welded up for me to find out why these motors are so sought after.

so mother nature has not been kind to san antonio, tx. awful rainy misty and low temps. but i did get the frame thrown together and was very impressed on how this motor had no trouble pulling me around.

so when the gx200 was in original form i had made my own intake to test out the motor with this carb.


but now i have rigged a homemade throttle linkage to do the work with a stock carb. all credit and thanks goes to the guys at www.affordablegokarts.com for this free throttle linkage hack.



in lue of keeping everything at its cheapest i solved the stock choke lever hold down problem with this hack, thanks to the wife, a hair tie. please dont be mad or anything later i will be purchasing one of those nifty hanger clip thingy, but later.


intake air is filtered by a scour pad from the dollar store held by a zip tie. free flowing and all but will be redone cause the pulse tube is just sitting there with nowhere to go.



so after the motor got the cheap makeover went for another ride. i definitely felt the power difference, and in the market for a cam that will let it breath a lit easier. the power is there.

this is a video of it running
https://www.youtube.com/watch?v=QkhKZr4ewoU

so i was fortunate enough to come across the subaru equivalent of these small motors. one is an ex21 and the other an ex17. from internet literature the subarus have more stroke but only 1mm less bore. that coupled with 4000rpm govn max these engines might be a little better. but of course when i started to look for its aftermarket hop up goodies, none were to be found. well at least what you would need just for a 'street setup' is there. billet flywheel, billet con rod, springs, but anything after that wouldnt you make your own part. exhaust, intake manifold, etc. well after some reading at numerous websites, everything from minibike, gokart, and motor powered canoe forums. most people have said that after using the subaru, that they liked it and would even use it more often if there was an aftermarket following. the only thing that can be done to this motor is to swap out parts with an kx21. if it wasnt for the price i would go for the cam at least but at $140 i can get the predator and wait my luck for another gx160 at the recycle yard. so with this new(old) motor that i get to play with.

switching heads, and thats about it. the ex17 flywheel has a 2 degree retard timing so i wont be using that, pistons are the same cams are the same, everything else is the same. no the chain smaller. the ex17 is a shorter cylinder.



head comparison of the subaru ex21 and ex17