200cc Tecumseh Build

happycheapskate said:
That's cool. I bet anything over 3hp will feel like a huge mill on a bicycle anyway. What do the china kits make, 1.5? 2?

What kind of bars are you going with, now you have stretched the frame. Are you moving the seat over the engine, or going with long handlebars?
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I was thinking the long handlebars, right now it feels like some kind of racing bike since you lean forward to reach the mountain bike handlebars. I could move the seat also though, if it was any lower or further back it would hit the back tire.
As far as the chinese motor bicycle kits, I think they'er supposed to be under 2 hp. This engine is a 6.5, 195 cc. The number is OH195ea.
 
happycheapskate said:
Sure. Just pull the plug and put a spoon full of 2 cycle oil in there, try to rotate it. If it turns over and the magnetos not to rusty, bet you can just spray the carb out, and run it if it was working before . I used silicone spray for starting fluid the other day on a Tech. and it started up good. took a little bit to get some gas through the carb.
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It isn't seized up that I know for sure as I was able to pull the starter rope and turn the engine. I also could hear the air flowing out of the exhaust on what appeared to be the exhaust cycle.
 
Heres the finished throttle, it's a grip shift thing for multi-gear bikes. If you take out the little metal piece inside it stops clicking, just a smooth pull.
The top of a tin can keeps the cable sheath from moving, but the cable passes through it. It actually works really well.
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What about the end of the handle bar, will you be installing a grip again? Do you think this will cause a problem twisting the throttle?
 
That's cool how you used the GripShift for a throttle. I thought of that before but wondered if it would pull the right amount of cable. If you get a piece of sandpaper and lightly sand your bars where the grips go, and use some rubber cement (not super glue), it works pretty good to keep the grips in place.
3M Spray adhesive works great.
I bet you will like it as a throttle, because with the rubber grip in place really well, you don't have to drill the bar for a peg on the throttle twister like the china kits.
 
Smart use of the twist shifter. Can you verify that it pulls enough cable to get you thru your throttle range? If not, you can buy (or make) cable doublers that are in essence two pulleys, one larger than the other. They change the amount of cable being pulled.
Watch for cable fraying at the can lid cable stop area.
 
It pulls just the right amount, it goes from resting on the idle screw to full throttle perfectly. The way its hooked up, the cable is connected to an arm, which is connected to the throttle, that's why it doesn't have to pull as far. At first the little spring in the throttle wasn't enough to make the shifter return to its position, because of the fiction in the cable sheath. So I added a mini bungee cord to counter balance it, now its easy to pull and it snaps back smoothly.
 
dracothered said:
What about the end of the handle bar, will you be installing a grip again? Do you think this will cause a problem twisting the throttle?
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All grip shifters come with this smooth plastic washer that goes between the grip and the shifter. Ill use it when I put the grips on.
For keeping the shifter on, I didn't have to use any adhesive, It has an allen screw that digs into the handle bars and keeps it on really tight. The throttle pull is really easy anyway so it doesn't have much force on it.
 
Sorry for the delay, but I can't get it started. It ran perfect just a couple days ago. It seems I'm not getting a spark, it does have voltage though I checked with a volt meter. I basically completely tore the engine apart trying to find the problem. I reset the camshaft to the market tooth, the camshaft is plastic. I took off the carb and sprayed it with ether. I checked the valves and they're not sticking, the gas is flowing to the carb just fine. I can't see a spark, thanks for any help.
 
Did you pull the spark plug and set it on the engine and watch if a spark jumps across the gap? Do you have a kill switch and is it off (not engaged)?
 
Yes I bought a new plug, clipped the kill switch wire, and I had it set on the engine, I couldn't see the spark. I tried it with the 66cc bike and I could see the spark just fine. I cleaned off the flywheel and the magnet with a wire brush, it had a lot of rust, so I'll try again today.
 
After cleaning off some of the rust on the flywheel, I tried one of the spark plugs from the chinese kits, and it was sparking. I got the engine to fire twice, both times it was really loud and something didn't seem right, but Ill work it out.
 
Could be a valve sticking. That's interesting about the china kit plug. It might be too long for your head. I put a J19LM plug from a briggs on a china kit. It ran but it was cold-natured and hard to start.

Have you tried the EZ Fire champion plugs or similar?

If you got it to fire, you're almost there.
 
The threads on the china kit plug are like half the size of the one that came in the engine. The stock one was a champion, and I replaced it with a NGK, which are pretty good I've heard. Its a NGK R BPR5EY. So the china kit plug is much higher up, should still work I think, and for some reason the NGK still isn't sparking, I even made the gap smaller. Maybe I need to clean some more.
I'm pretty sure the valves aren't sticking, I checked them twice already and sprayed them with some lubricant. When I pull the starter, They move up and down consistently.
 
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