bicycle engine total tear down

Norman, what do you think of that engine? I have one like it from Kings. The reason I am asking is that I see it is a one piece crank, in that the flywheel weights do not come off. All the other engines I have the part that goes out over the bearings is attached with three screw's, I am thinking that the engine like yours vibrates more! On the other engine there are hollow places near the big end to compensate for the extra weight, that engine doesn't care. Have fun, Dave

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The engine with the bolt on weights have came apart( weights coming off) so I should not have to worry about that on mine. You could balance any crank by drilling it but I'm not worried about it, mine seems to vibrate at idle and runs good when under power. I'm happy with it so far. These engines are in my opinion, the bottom of the barrel rejects, but they are fun and cheap.
Just right for a motor assisted bicycle not meant to be a moped or motorcycle.
Norman

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motor assisted bicycle engine headlights that work off of your white power wire. check it out

10/4 that is what I think also. I have the one like yours in a Schwinn cruiser, the avatar. That bike has the most vibration but it has the worst mounts also. I have the diamond frame bike with a Dax engine and that has the removable weights, also the best mounts but still not the best for smooth. The bike I call the Green Hornet is as smooth as a good motorcycle also a Dax, I am thinking the mounting is an important factor, I am going to do an extra plate to pick up the bottom of the engine on one of the bikes to see if it helps. Working for Honda years ago there was a problem with the MT250 the motor mount was in a bad place and would crack and then would just about tear the bike to pieces welding was not good, the metal was so brittle it would just crack again, very hard to fix. Thanks for being a good sounding board, if I talk things through I solve the problem. These engines are a good place to relieve tension. I have not had a problem with the weights coming loose yet. Have fun, Dave

I found the diamond frames to be smoother running between itself and the cruiser type, coincedence?

I think it has to do with frame geometry and tube wall thickness/diameter.

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If it ain't broke, and you mess with it long enough, it will be.

Look at the (Moon Dog), my Green Hornet, I think that is what it is called, from W Mart. The reason I am saying this is that the frame is so small the engine just fits. I needed to take the top end off and had to take out the studs to get it off with-ought taking the engine out. What I am thinking is that, it being so small that it has strength! I used one of those flat plates to hold the engine in the front, I don't like them, but it is still smooth running. I would like to exchange the engine from the Schwinn but I don't want to mess up the paint, I would like to see if my idea is correct. Have fun, Dave

Your right Dave, smaller opening/stiffer frame.

Funny thing is, I looked at the Moon Dog today at W-Mart, and the frame is completely different...it's more of a "schwinn type" without the dip like the (older) Moon Dog has.

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If it ain't broke, and you mess with it long enough, it will be.

Yea, I was over there today also and noticed the bars are not reversed any more. The next bike I want to make, I want to try and put an engine on a full suspension bike. I want to try and put it out in front of the frame completely and use the top of the engine and the rear of the engine for a mount. If I use a steel frame I can weld on it, I need to change the fork angle to get a little more room. Ill keep you posted. Have fun, Dave
PS: I am in Utah now and all the bikes they have at W mart are under 100 bucks, that Moon Dog is 89.oo.

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Chuck - The monkey has the spark plug again!

New to this.
I have a 70cc 2 cycle and bought a pull start for it but cannot get the nut and washer off the shaft in front of the magento because it keep's turning,tried holding the gear's but still turn's?
It's a little different from the look's of you're photo's or if you know somebody that could help me.
Thank you.

sailor49618

bjjm@copper.net

take off the clutch cover and as you trun the nut on the mag side you can take a shop rag and let it jam in the gears of the clutch side. It will stop the crank in its tracks and will do the same thing when you put the nut back on just stick the rag in the gears and it will lock it up don't stick your fingers in there with it or you will learn all kinds of new cuss words and all the neigbhors will too.

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norms-iron-works.tripod.com
motor assisted bicycle engine headlights that work off of your white power wire. check it out