Time for a new Horizontal Hit and Miss engine

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Don't you have an old ball point pen laying about you could steal a spring from. I've usd that sort of spring weight a few times on governors. The one in your photo looks quite thick gauge.

You could also try reducing the throttle opening so the engine runs slower to start with.
In this video, I have added some weight to each of the governor weights. The pieces I have added are 0.545" diameter brass x 0.100" thick. It does let the engine run at a lower speed, and it does give longer "miss" cycles between hits. This is a very noisy engine, and I think that most of the noise is coming from the governor assembly itself. Anyways, I achieved what I wanted to, thanks for having a look.----Brian

I like the way it runs now. I agree with Steamchick that it demonstrates the hit-and-miss action very well.

My inquiring mind wonders if one of your many mechanisms would provide a load that would show it even more.

Thank You for Posting.

Surely a load will have the engine hitting more as it tries to deliver the power to drive the load to a point where it only hits, engine speed should remain fairly constant.
Yesterday I posted a video of the engine running with 0.545" diameter x 0.100 thick weights added to the governor. It did slow the engine down some. Today I decided to replace those added weights with new weights 0.75 diameter x 0.100 thick, to see what would happen. I am pretty sure that this newest move has slowed the engine down even more, but I have to listen to the two different videos and see if I can hear a difference in the engine speed.
I'm still looking at ways to slow the engine down. I have removed the extra governor weights and put on a lighter governor spring. The result of course, is now that with the lighter spring, the governor weights fly out and put the engine into "miss" mode far to easily. If I hold the governor arm back from engaging, the engine starts and quickly accelerates to a scary rpm. Then if I release the governor arm, the weights immediately fly outward from centrifugal force, the governor arm engages and prevents the exhaust valve from closing, and the engine slows down far too much for the engine to start firing again. The rpm is so low now that the engine doesn't fire and recover speed. It just quits. Right now, there is no means of adjusting the tension on the governor spring. I think perhaps my next trick will be to design a tension adjusting device for that spring.

I was referring to the "action" of the governor taking the engine into and out of the hit mode or miss mode rather than the speed of the engine or the continuity of the firing or coasting in general.


I am with you on your investigation into the speed of the engine combined with the action of the governor to find a "sweet spot" for this engine's performance.

I really enjoy your posts like this where you apply changes step by step to reach the goals you set for each project. I enjoy your designs for changes to get what you want. Can't wait to see what form the tension adjusting device takes.

Hi Brian !
My way is : lock the hit & miss mechanism
Adjust the engine so that it runs as slow as possible :
- Reduce friction and make parts as smooth as possible
- Reduce the force of the intake valve spring
After the engine reaches a slow speed that I accept, I will adjust the hit & miss mechanism
I lay in bed last night thinking of a suitable way to make the spring tension adjustable on my governor, and still keep the weight of both governor arms equal. I have come up with a plan that will work but requires me to make some small pieces to do it. I'm not moving around very well these days--I have to have both knees replaced, and I'm waiting for a call from my surgeon. I can move around slowly and set on a stool to do my machining and in my orthopedic computer chair for designing.
And a nut will do to lock the adjuster
Today was spent making little bits and pieces. I know that I only needed to put adjustment on one end of the spring, but I also wanted the weight of each arm to be equal. The spring shown here may not be the one I use, but I wanted something in there just to take the picture.--And yes, Jason, there will be locknuts backing up the aluminum adjusters to lock them in place.
I was thinking of tapping where the adjusters pass through the weights and then just a nut to lock them. Also no really need for the pin that you have the adjuster passing through the spring will pivot in the hole sit hooks into.


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I'm happy!!! The adjustment added to the governor spring tension has let me dial this engine in to "As good as it gets".--Note that there is a locknut on only one of the knurled aluminum adjusters.--I only had one available. The rpm is slower and the "miss" cycles are longer. Now I can put this engine "up on the shelf" and spend some time dialing in my v-twin engine to give better results.

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