pressure washer yammy.

A few months ago I picked up this older maybe 70s Yamaha dirt bike frame. About a week ago someone gave me this 110cc Chinese quad engine for free but its missing a carb and a spark wire. Could someone with a little bit of electrical knowledge tell me what wire goes to the spark plug? After a little measuring I figured out that the sprockets are compatible but now I don't know what # of chain to use. Before I mount It I will buy chain and make sure I can align them. I really don't care if its completely slow or really fast for now. For now the plan is to buy a carb, Clean out the gas tank, figure out the electrical and get a chain.

More pictures of the wiring. Could I simplify this at all? is it necessary to have the solenoid? What wire is the spark wire?

I think Fearlessfront used a similar engine for his weirdo pinto offroad "mower" thing, you might be able to get some info from his videos, or at least a view of a complete engine lol. Not sure about the wiring myself.

As for the sprockets, I'd say that's #50 chain, but you can measure the distance between the teeth and see.

Keep us updated

Thanks Rich but most Chinese quad engines use 420 chain so i'm thinking its #420.

Could be. Measure your sprocket before making any guesses though.

A lot of motorcycles are 520 chain. You might be able to search for yamaha dirtbikes close to the year and model you think you have. If you can find a model close and with about the same power, the chain will probably be the same. I think there's probably only a few sizes to work with so it shouldn't be too hard. I would say either 520 or something smaller, but I don't know the number of the next size down off hand. As for the plug wire, who knows. It should be separate from that wire harness. Probably coming out from behind part of the case? The coil has to be in there someplace. Maybe it got ripped out somehow so look for a hole it might have been through. The carb is probably fairly cheap online. Just search for 110cc atv engine carb or similar. You should be able to get one brand new that's ready to go for that engine. Maybe $30 or less.

(edit: yeah what everyone else said about chain size, I don't know too much about those chinese engines)

They have a stand alone coil. Buy one off a moped or another Chinese quad. Could probably save a headache and buy a Chinese ATV wiring harness and just plug it in. Also, measure the intake manifold and see the bore diameter, also measure the distance between the mounting bolts so whatever you get will work

I have a 110 Chinese atv so I know these things fairly well. I read up on how to get a little more power out of them and found that you can port the intake manifold because they are really jenk from the factory

Thanks Mr. Modified. I will look for a spare hole in the case. It would probably be sticking out by the magneto right? And yes I have looked at the carbs for them before. I want one for the LT130 too. They are about 20$ at the cheapest. So you think that the two sprockets don't match? I measured the distance between the two peaks on the sprockets. They were the same at about 12.7 or 13.7 mm I cant remember.

Measure the width of the sprocket and distance between the valleys on the teeth. Values in standard.

Thanks CQ, what is a stand alone coil?. and for finding space for the carb, I wont worry about mounting bolts for now because I will make a 90 degree twisted elbow and it will just be hanging off the side. And for power, I am fine with 110 on a bike, however on a quad like you have, I would like some more power, I was looking at a 110 cc quad for sale for 125$ but I didn't buy it because I am looking for something a little bigger.

Cool diagram Rich, what is the difference between the standard dimensions and the others? What would be the distance between the valleys on the chart? would it be pitch or roller diameter? because the roller kinda sits in the valley and the valley's depth isn't exactly half the roller.

Motorcycle chains have different widths. Only really gotta worry about the pitch for what you're doing, I'd think. Pitch is the distance from valley to valley. I'd be #50 chain would do ya, even if the sprockets were for #520. So if the distance from valley to valley is .625" (5/8") get #50 chain.

So #50 works for Mototrcycles but does it work for the Chinese quad engine I have?

Is #50 chain super rare or is there another name for it Rich? really hard to find it on ebay...

Did some engine mounting today. Just working on the brackets but i'm not going to weld them in place until I know that the 2 sprockets line up. I am just wondering if anyone knows anything about the engine. It is an automatic but its off an ATV so i'm wondering id there is a reverse even if I wont need it.

The plate just gets bolted to the bottom and then I will weld little brackets to the bottom bar.

Ok so it has been a while, but I scraped the idea of the atv motor just because of the ignition system, I got this pressure washer for free, and I took the engine off of it, I modified the frame a little bit, made an engine plate, and I just need to order a centrifugal clutch off of ebay, weld on my plate, install a few cables, and this thing should be almost ready.

Got the clutch for this thing a few days ago, so I decided to get to work. I welded up the engine plate onto the frame, got a chain, chain tensioner and the clutch on, rigged up this exhaust that I like for some reason, and made new mounts for the gas tank.




Now all that's left is to finish my new intake manifold and get a air filter, rig up some sort of fuel line, and most importantly find a way to make a throttle, which I am not to sure how to do yet. Oh yeah, and also make a seat somehow, but who needs a seat lol.

Nice progress! I actually dig that exhaust you got going on there, pretty simple but it has a real cool look to it.

What are you thinking for an air cleaner setup?

Looking good! Does this thing have brakes?

RichieRichOverdrive wrote:

Looking good! Does this thing have brakes?

It does, I might take apart the back brakes and free everything up and hopefully get them working. Too too concerend about the front brakes.

AllisKidD21 wrote:

Nice progress! I actually dig that exhaust you got going on there, pretty simple but it has a real cool look to it.

What are you thinking for an air cleaner setup?

Thanks, I started making a little flange and tube to come out at an angle to replace the stock housing that doesn't fit anymore. I will put a pod filter on it and post a picture when i'm done. I like the exhaust too. I hope its still quiet.

Did you math out the gear ratio? Looks like it would be awful high?

TheBeal wrote:

Did you math out the gear ratio? Looks like it would be awful high?

I was concerened about that too. I'll just have to see. I hate jackshafts.

What has you concerned the most about building the throttle?