Thumper---A new 1 3/8" bore i.c. engine

[RB211]

As I also mentioned, yes it is his, and his to do with, or not do with, as he desires.

I admit that I, in common with others, I am sure, end up feeling a bit let down when there is a long build thread (your post was #385) about an engine, and then it stops short of what was the original goal. It's like reading a good book, and finding that the last half of the last chapter is missing from it.

It feels a bit different when you have been following the build, and then....... Yeah, I get it, I already said so, but you know.....

Perfectly understandable

[J Tiers]

These engines are built for Brian's own interests. All of you are able to buy his plan set, build your own, modify it, improve it, and post on here about it. I would assume Brian has grown tired of this engine.

As I also mentioned, yes it is his, and his to do with, or not do with, as he desires.

I admit that I, in common with others, I am sure, end up feeling a bit let down when there is a long build thread (your post was #385) about an engine, and then it stops short of what was the original goal. It's like reading a good book, and finding that the last half of the last chapter is missing from it.

It feels a bit different when you have been following the build, and then....... Yeah, I get it, I already said so, but you know.....

[RB211]

These engines are built for Brian's own interests. All of you are able to buy his plan set, build your own, modify it, improve it, and post on here about it. I would assume Brian has grown tired of this engine.

[Sparky_NY]

I certainly agree, but it is Brian's engine and his decision.

Maybe he will come back to it later. It would be very disappointing and discouraging to me if I spent a long time on a project and it did not do what it was intended to do. I understand being "done with it" at least for a while.

Yes, it was intended to run the edger, and it failed, possibly for something as simple as not increasing the throttle under load. Brian often chooses to totally ignore extremely valid suggestions others make to refine his builds, its his builds, his threads and his engines. Everyone has different quality standards they work to achieve, its a personal thing. I follow many engine builders out there, Brian, Gbritnell, Sid and many more.... all of them are interesting and quite different at times in their approaches and finished products. Variety is always a good thing.

Kind of reminds me of looking at cheap used cars, the statement "it runs" covers a LOT of territory !

[J Tiers]

Brian, This engine deserves better. Shelving it without even an attempt at manual throttle control makes no sense.

I certainly agree, but it is Brian's engine and his decision.

Maybe he will come back to it later. It would be very disappointing and discouraging to me if I spent a long time on a project and it did not do what it was intended to do. I understand being "done with it" at least for a while.

[aostling]

Brian, This engine deserves better. Shelving it without even an attempt at manual throttle control makes no sense.

[Captain K]

Brian
I always follow along and really enjoy your builds. You would need to open up the throttle when you in the cut if you want it to work. Raising idle speed will not help. If it still stalls out at wide open throttle then you are definitely out of luck. Can’t wait to see what you dream up next

[Willy]

Brian you are of course correct. The engine is a smooth running one that is very appealing and aesthetically pleasing as well.
Not only has it been a treat to witness the build but it is also one that showcases your design and machining talents on a job very well done.
This is of course a home shop machining forum and not one that addresses internal combustion thermal and volumetric efficiency, we can leave that to another thread.

Take a breather Brian, and a bow to a to another incredibly beautiful engine. I think anyone here would be proud to claim it as their own creation, I know I would!

[The Artful Bodger]

Thank you Brian for the enjoyment of following you on your adventure with "Thumper". John

[brian Rupnow]

Paul--I'd say you have that about right. I enjoy the design and building, and no load smooth running. I like them to be "pretty". I don't care to invest a lot of time "tweaking" the engine after the fact. I'm ready to move on to my next project.-----Brian

[PStechPaul]

Unless the throttle is at least half open, I don't think it would be correct to say the engine does not have enough power to run the edger. It is simply starved for fuel. An easy way to measure performance is to hook up a DC generator (treadmill motor) and a bank of light bulbs or power resistors (heaters). You can add to the load 40, 60, or 100 watts at a time and open the throttle to get the desired RPM. Measure the voltage and current to get power, and you can then compute the torque.

This could also be a way to provide a sort of governor. Add maybe 500 watts of load, and then run the board through the edger. If that is only a 1/4 HP (200 watt) load, the added load will be a smaller proportion of total, and it should be able to do the job.

Brian, it does seem that you mostly enjoy the design and machining of gas engines, and their ability to run smoothly at idle and rev up with no load. And also, perhaps paramount, is the aesthetic beauty of the finished product, to be displayed proudly on a shelf. And that is certainly understandable and admirable, and I enjoy reading about your progress with these engines. I'm a more practical oriented electronics guy, so I'd be working on an engine analyzer and computer-controlled engine management.

[brian Rupnow]

And that's all she wrote. Time to move on to a different project.---Brian
https://www.youtube.com/watch?v=BZjt...ature=youtu.be

[aostling]

... the flywheel fans do move enough air to constantly be moving air over the cylinder fins and dissipating the heat. .

Cleared for take-off. Goose that throttle.

[brian Rupnow]

I have a few things to say about this engine, and immediately after I do I am going to go out into my main garage and try it one more time running the edger with the new manual ignition timing handle to see if it does make the engine run stronger or not. Firstly, I am completely blown away by the compression this engine has with the rings purchased from Debolt. Secondly, the flywheel fans do move enough air to constantly be moving air over the cylinder fins and dissipating the heat. They're not going to blow your hat off, but they are moving the air. Also, there is no measurable load imposed on the engine by these fans. (At least not with any equipment that I have). I will not be building a governor for this engine. The engine has been a complete joy to build and run, and even if it doesn't ultimately have enough power to run the edger, the engine has went together and ran easily.

[Sparky_NY]

Obviously a governor is the best solution, but it seems he has little appetite for any further fiddling with the engine, which was, after all, supposed to be powerful enough to handle that sawmill.

As I suggested before, manually adding throttle when it starts to bog will answer the question if the engine is capable of developing enough power. Only then would a governor be a consideration. IF the engine just isn't capable of developing enough power, a governor isn't going to help one bit. Hard to believe Brian is avoiding such a simple test.