[Arsenal]

Ok, this is the first motorbike I’ve ever really messed with. I found it in my barn buried next to tires, and I’m pretty sure it belongs to my dad or my uncle. Basically I’m just asking for any information you know based off of these pictures. I wanna try to restore it to an operateable condition. The biggest problem I know of is that the chain and “clutch” (the thing that connect the chain to the engine) is gone or maybe broke off. Also the bike has been sitting for a long time and I’m worried about the gas tank. I don’t think it’s too bad if I’ll just take it off and swish some gas around in there to clean it up a bit. However, I need other people’s perspectives on it as a more experienced person. A slight problem is that the handle that you use as a throttle doesn’t move, but I’m sure I’ll free that up just tinkering with it. I’m assuming that’s all is wrong with it currently and if I get any information I’ll keep the thread updated hoping it helps. I attached some numbers I found on the side of the engine in case those are helpful somehow. (I tried, but couldn’t find how they were helpful)
A little background info about me is that I live in the country and have a little experience working with small engines and the such.

 

[cmonSTART]

Good for you for taking that project on!

You are missing your front sprocket and chain - those you will need to find or source new ones.

The tank is fine - that's really minor IMO.

Welcome!

 

[Arsenal]

Thank you! I knew about the chain, but any idea on what kind of sprocket it could be fitted with? This is where my knowledge cuts off on motorcycles.

 

[hogcowboy]

Sure would be nice if introduced yourself in the New Member Introduction forum so we could get to know you a little. It really doesn't hurt too badly.:grin:

 

[Arsenal]

Thank you, I will do that later. I was just trying to get it posted real quick inbetween college class assignments. I got some new info on it and it’s been sitting there for roughly 30 years or so. A little small engine revival isn’t too hard, but I’m worried about the transmission. Is there a way to check it or free it if it is seized? I didn’t get around to trying to go through the gears yesterday when I pulled it out.

 

[McRider01]

I think Kawasaki went to uni-track (single shock) rear suspension around 1981, so your bike is older than that. You might try this website with the engine number to get and idea of the exact model and availability of parts: Vintage Kawasaki, Online Store

 

[Arsenal]

This bike has no gauges, lights, or anything that seems like it needs a battery. I haven’t got back to checking it out, but it should have a magneto instead of a battery, right?

 

[meierjn]

I think Kawasaki went to uni-track (single shock) rear suspension around 1981, so your bike is older than that. You might try this website with the engine number to get and idea of the exact model and availability of parts: Vintage Kawasaki, Online Store

I had a KDX 80 that I believe was a 1981 model. It did have the monoshock as well as a plastic gas tank. It was a great bike!

 

[Arsenal]

I am going to clean the carb within the next few weeks and hopefully get the motor running. When I get the motor running and the clutch and gears ready, I will buy a sprocket. However, the bike doesn’t seem to want to go out of gear. When I push gently on the kickstart, the place where the sprocket goes moves. I read somewhere old bikes only go into first gear while the engine is running, but if this is true why won’t it stop moving. The gear shifter acts like it works to go up, then also down once after that. Any ideas?

 

[McRider01]

The bike may be in gear and without a chain and sprocket it's going to be hard to know when you are in neutral. You need to be able to rock the bike back and forth while you move the shift lever to select different gears and this can only be done with the chain and sprocket in place.

 

[Unkle Krusty]

The big round part of the exhaust, above the cylinder head, is an expansion chamber. The rear end of the exhaust is the muffler. Bikes with expansion chambers and knobby tires, are usually motocross bikes. MX bikes are designed for MX races, with an appropriately sized rider. MX bikes do not have lights or any street legal stuff. They are for off road use only. If the is no room for a battery, or any wyring, then it does not have a battery. The zap for the spark plug will come from a magneto, which is always switch on, unless the kill switch is activated, either by pressing or switching. It is a 2 stroke and needs oil mixed with the gas. Forgot how much but 32 to 1 should do it. If you find an oil pump and an oil tank, then you do not need to mix the oil and gas, but I suspect it is a premix.
Remove the spark plug and pour an ounce or two of oil in the hole. Check that the motor turns over by using the kick starter or a spanner on the end of the crank shaft. Turn it clockwise when looking at the engine from the right hand side. Put your thumb over the spark plug hole and turn the engine. You should feel pressure against your thumb. Buy a compression gauge. Make sure the slide in the carb is going up and down. Open the throttle so the slide is up, kick it over and check the compression. Connect a spark plug to the end of the black wyre appearing from under the tank, lay it on the head, kick it over and check for spark. Clean the carb. Make sure the cable and slide are moving freely. Put a front sprocket on and a chain. Find neutral. Install some fresh gas and oil. Make sure gas flows to the carb. If it has spark, and 90 pounds of pressure or more, it should fire. Start with an NGK number six plug to get it fired.
It probably takes an 8 or 9. Check the specs.

Find some one that has some bike knowledge. Use a good two stroke oil. If you do not get the oil to the engine you will seize it, and have more problems than you need at this stage of your new incredible adventure.

Bon chance UK

 

[Arsenal]

Thank you, thank you, and yes I am sure the engine is not seized. Yes, it is premix and yes I already did a compression check with my thumb. I did it gently barely moving the kick start, but it still created some compression. I didn't wanna go too crazy with it without oil being in the engine. I've tried not to turn the engine due to the fact that it will seize, however, thank you for telling me I can put a little bit of oil in the hole to prevent seizing. I think I have a compression gauge laying around somewhere in the shop. The previous spark plug was a B9ES. Is there a way I could test the ignition coil before the new spark plug arrives? I am trying to keep costs down, until I have proof the engine will run.
I know it may seem as a noob question, but for the first start in 30 years, should I use carb spray or starting fluid? I know that's an easy way of helping old engines crank after a proper cleaning, but I am unsure of how you'd be able to spray it in the carb right before you crank.

 

[Unkle Krusty]

Pretty much any spark plug will do to test for spark. Just plug it in to the cap, and place it on the cylinder head. I forgot to mention, make sure there is oil in the gear box.
For the engine, mix one gallon of oil and gas to start with.

UK

 

[Arsenal]

Use 1 gallon gas to 1 gallon of oil? Is that what you’re saying?

 

[hogcowboy]

No. That would be a 50/50 mix. He mentioned earlier that he thought a 32 to 1 mix was the correct mixture.

Forgot how much but 32 to 1 should do it.

 

[Arsenal]

No. That would be a 50/50 mix. He mentioned earlier that he thought a 32 to 1 mix was the correct mixture.

I figured, but just making sure because I got thrown off at the end. I’m going to town to get fuel lines and in-line fuel filter the day I do the carb. It’s a simple job that’s just gonna take time. Banking on me having nothing to do on the day I’m off. (18th)

 

[Arsenal]

Forgot to ask, will the compression pressure change before and after cleaning the carb?
Also, would it hurt to run 15W-40 motor oil in the premix for the engine? I’m asking because I’ve got a buttload if it sitting around.

 

[hogcowboy]

The two stroke guys will have to answer that. I'm clueless in that area. My gut says no problem, oil is oil, but this is two stroke and I'm just completely ignorant with them except my chainsaw. But it's the chainsaw that makes me think you can burn anything. It might need a different ratio is all I can think of. But lets let the gurus chime in.

 

[Arsenal]

Another question I forgot to mention:
How will the front sprocket stay on? Do I need to get something that isn’t in the picture above? Or will just an ordinary front sprocket work? (As long as it correlates with the chain and rear sprocket)

 

[Unkle Krusty]

You need a quality 2 stroke oil, which mixes well with the gas. Regular engine oil will not mix properly. You need 32 parts fuel, 1 part oil. US gallon is 128 fluid ounces. Divide that by 32, gets you 4 ounces per gallon. Mix it well. After you have the bike running for a while, you can check the plug. A number 9 with compression on the low side, will probably be a bit sooty all over. Later with a compression gauge, if you get around 140, you should be good to go. Depending on the quality of the spark, you might need to run a number 8 plug, which fires a little hotter. Or you may need to lean out the oil in the fuel a bit. The starting point was 4 ounces, drop it down to 3.75 ounces. Ultimately you want the engine to be running clean, not much smoke, and for it to stay running, as in not seize.

The throttle needs to be wide open when doing a compression test. The screw in type works best. Kick it over several times and watch the gauge pump up. 90 is usually about the minimum to fire. Any less and the rings are probably stuck.
Make sure the slide in the carb goes up and down nicely. There is a big spring inside, that should close the slide with no effort. You can stick lift the slide with your finger to check.

UK