Flying Horse 66/80cc Wiring: Help!

Here's a diagram that shows what Boxcar is saying.

I also agree not to use the white wire, for anything. In fact newer magnetos come without it.

The kill switch is a safety device. You can't shut the engine down with the clutch when you're riding and reaching down to fumble with a choke lever is asking for trouble in an emergency situation.

Jerking the engine to a stop with the clutch, even at idle speed is putting stress on parts, woodruff keys, etc. Install and use the kill switch as it is designed to be used.

Tom

"really big hill on my route"

Hmmm. We have to wonder just what you mean here. What are you considering a really big hill? You have to keep in mind that it is a motorized bicycle and not a motorcycle. Hills can be tough and will slow you down. Some, depending on the % of grade will require you to to pedal assist. Bicycle, remember?

If your routes have a lot of uphill you might want to consider going to a larger rear sprocket. That is like going to a lower gear in a car. It will decrease your top speed some but will enable the engine to pull harder up hills. A 48T or even a 56T sprocket might help your situation.

You're correct that the engine will produce more power after break in. In some cases it will be substantial. It might be enough to tackle those steep grades but if the hills are "really steep" it won't be enough.

A better exhaust will help a little but don't look for neck snapping performance gains especially on hills. Expansion chamber exhaust systems are for high top end performance. Not hill climbing power.

Proper carburetor tuning is critical to power output too. There are pages of discussion here on carb tuning/jetting. Too much information to cover here. Almost without exception the stock carburetor will perform better with a smaller main jet (leaner fuel/air mix). I'd wait until after complete break in to start experimenting with that.

As for performance upgrades, there are many. I wouldn't suggest going too wild with modifications until you have a firm grasp of the engine and you need to consider longivity. A highly modified engine producing maximum horsepower will not typically last as long as well maintained and tuned stock engine. Ask anyone who races and they'll agree that they don't expect to get thousands of miles from a race engine.

There are a lot of after-market upgrades. Some work, some are just snake oil. Don't fall for terms like "racing" "High Performance" "Speed", those are marketing come-ons that usually produce performance gains only in the minds of those who paid good money for them. Carburetors and ignition systems are examples.

Hope some of this helps. You'll get other opinions so be patient.

Tom

Panama,
Loved the hill climbing blog. Fun reading. Thanks.

As for Loctite, thread locking compound. There are a number of us who highly suggest against using the red, or permanent variety. Loctite product #262 comes to mind. Even though a great product you'd be better off with a non-permanent thread locking compound. The red stuff works too good in that it requires the application of heat to remove a fastener after the compound has cured. There's no need for such security. The blue Loctite, product #242 will do everything you want and still allow things to be disassembled without heating.

Proper torque is also important. Don't under-do it, but also you don't want to break things. Those little 6mm fasteners can only take so much, about 60 inch pounds will suffice. 8mm fasteners can take 120 to 140, some say 160 inch pounds. I wouldn't suggest exceeding 160. You're pushing your luck.

Recheck engine fasteners after a couple of heat/cool cycles to make sure they are still at their installed torque.

Good luck.

Tom

That's a fine looking build, Panama. You've done well. Congratulations.
It's very clean and a lot of attention to detail.

As for storage; unless your fuel mix contains a stabilizer you'll want to drain the fuel from the tank and carburetor. 2 cyle mix has a relatively short shelf life and doesn't store well in fuel tanks or carbs.

Depending on where the bike will be stored you'll want to assure it is kept dry and out of the elements. Of course security against theft is another concern. Other than those things storing for several months shouldn't present you with any problems.

Sprockets: As long as the sprocket is compatible with your adapter, (rag joint) either of the ones you linked should work for you. Of course you'll have to go through that process of installing it again but you suceeded once and know how to do it. Naturally a bigger sprocket might require a slightly longer chain so plan on adding a couple of links if necessary.

Hope this helps and answers some questions for you. Good luck, have fun and please, ride safe.

Tom