My Classic American Mini-V-Twin

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JamesDTaylorSTL
Posts: 6
Joined: Wed Apr 13, 2016 6:59 pm

My Classic American Mini-V-Twin

Post by JamesDTaylorSTL »

I just wanted to show other mini engine design/builders my "Classic American Mini-V-Twin Engine" and see what they think. It was actually my first design/build and it did run on first build after getting the propane fuel/air mixture right. So I was quite proud of that.

Well here are a few pics. Along with the exquisite Franklin Mint die-cast model I had planned to mount a running engine in. How cool would that be?

Thanks for looking!

PS. I am also selling this engine and all the "technology". As such many other pics are also located in the eBay section of this forum so please take a look and pass it along to anyone you think might be interested. Thanks!

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Last edited by JamesDTaylorSTL on Thu Apr 14, 2016 5:55 pm, edited 2 times in total.
JackF
Posts: 1616
Joined: Mon Jan 26, 2009 3:56 pm
Location: Caldwell, Idaho

Re: Classic American Mini-V-Twin which BTW is also for sale.

Post by JackF »

Hi James, welcome to the Chaski forum. That is some beautiful work. Did you take pics of your progress during your build? If so that would make a good new build thread. :) Hope to see more of your work.


Jack.
JamesDTaylorSTL
Posts: 6
Joined: Wed Apr 13, 2016 6:59 pm

Re: Classic American Mini-V-Twin Engine

Post by JamesDTaylorSTL »

Thanks Jack. Unfortunately no. I was just not thinking of that back then as I was trying to keep it under-wraps until it reached production. But I'll add some more details below.
Last edited by JamesDTaylorSTL on Thu Apr 14, 2016 5:52 pm, edited 1 time in total.
JamesDTaylorSTL
Posts: 6
Joined: Wed Apr 13, 2016 6:59 pm

Re: Classic American Mini-V-Twin which BTW is also for sale.

Post by JamesDTaylorSTL »

JackF wrote:Hi James, welcome to the Chaski forum. That is some beautiful work. Did you take pics of your progress during your build? If so that would make a good new build thread. :) Hope to see more of your work.


Jack.
Well in lieu of pictures here is some more information on it that is a cut and paste of replies to questions that were asked of me by potential buyers.

I’ve received a lot of technical questions regarding my engine eBay auction so below is a summary of my answers that may be helpful to anyone interested. Yes I had one engine up and running. But only at a constant speed of about 2500rpm due to the limitations of my knowledge and how hard it was for me to try to, all by myself, correctly blend the output of the gas regulator and cable operated, filter housing variable air restrictor and the ignition timing adjuster I used. My wife had a short video of the first time I got it running (an exciting moment as I'm sure you know) but we are long divorced and now she "cannot find it"... And I had to put the project on the shelf as I needed to start focusing on real work again at the time.

The only problem I had with the admittedly limited run-time engine was a crankshaft/flywheel key backing out of its slot due to it only being held in place with red/permanent Loctite. But I was planning on an easy fix of just adding a small screw to the end on the shaft so that the edge of the screw head protrudes over the slot just enough to make sure the key doesn’t work its way out over time.

Beside fine-tuning the only other modification that I currently think it may need is to lighten the relatively heavy, "boxy" stainless steel rocker arms as I believe that they may have been floating some at higher rpms but this would be very easy to do with the multi-axis CNC's that these parts are already being made on and I'd be happy to change the models to accomplish this. Other than that I feel that the core-design is very sound and based upon proven design methods

The piston rings (one per piston) were made by a knowledgeable mini-engine ring supplier in England who's name escapes me right now but I have about 25-30 so you would be set for quite a while.

For the push-rods I had come up with a way that I had not seen( at the time) to make them pretty light and make valve adjustment pretty easy and the cam followers were ball bearings (admittedly with a bit of concern of mini-bearings ability to take the cam "hit"s) But these can obviously be made standard way such as with solid rollers. But I wanted reduce operating friction as much as possible to help to be able to get the lowest idle possible.

Lubrication was wet-sump/splash with a crankcase check-valve breather. The cylinders have steel liners that were precision honed to size by Sunnen Machine Corp.

As far as the ignition, I planned to use very small Hall Effect sensor mounted to the cam shaft. You'll note that the camshaft on the prototype protrudes from the cam cover. That was just temporary because I was using a large sensor/magnet wheel. As far as the ignition itself; I had planned to mount that in the wood base and just run hidden plug wires through one or more of post that the engine is bolted too as I wanted the engine to be exposed on a pedestal making it obvious to anyone that it was really running on its own. The unique (well at the time) spark plugs were of my design and were pretty close to scale using only a 6-32THD and worked very well.

For the butane/propane gas injection (should someone go that route) I had planned for it to be easily controlled by a electric proportional control valve similar to this: http://www.ebay.com/itm/CLIPPARD-Propor ... 3641.l6368 I chose not to use a liquid gas carburetor as I wanted to sell these to the average person and not just mini-engine enthusiast. That way "fill-ups" would be as simple as filling butane lighter and by using a gas there’s no carburetor cleaning/clogging and liquid gasoline leakage safety issues to worry about. As for controlling the cable operated, filter housing “variable air intake restrictor” I had planned to control this with an electro-mechanical servo like used in remote control toys. Therefore ultimately the throttle control would be drive-by-wire which could be a simple lever, knob or even a replica motorcycle throttle. This would also allow for micro-computer (costing about $20) controlled automatic adjustment of the fuel/air ratio for cold starts, max run times, high temp prevention, etc. And these could even be easily changed later via an internet connection and a USB cable. I also have people who could assist with the electronics/software control if someone decide go that route. Same for any final engine fine tuning.

The starting system and the use of a flywheel is up to the user. I designed two of the largest stainless steel flywheels I could squeeze into the cases and they are actually pretty heavy. The flywheel/degree wheel you see in the pick was just for initial debugging. And the compression was going to be just enough to maintain running but it would not be capable of doing any real "work". But if I was going to mount a flywheel mounted to the crankshaft
(which as you will see below I was not) it would probably be hidden behind a simulated brick wall or mounted down in the wooden base as I have seen other do which I figured would be up to the buyer.

And yes you are correct as I've said and written many times myself (including in a pending patent application) the physics of flywheels does not scale proportionally. As such I had designed a unique and very likely patentable low RPM idle technology necessary to get the traditional "potato-potato-potato" sound and aesthetics (ie no large flywheel) that I felt was a necessity in selling an engine like this and that also allowed it to still qualify as an actual running engine.

As for the previously mentioned unique and very likely patentable starting low-idle engine system technology; that would require additional discussions and NDA agreements. But at first I did not want to connect that with the sale of this engine design but I am currently re-thinking that. I know that may sound like" smoke and mirrors" but I can assure you it is not. But I do not want to disclose technology to just anyone who ask. But I am willing to outline this technology to one or more (not connected to me) well-known mini-engine industry experts (if they will sign a simple non-disclosure agreement) for a legitimately interested buyer.

And I might also mention I'm a mechanical engineer with over 28years of experience (much of which included working with and for patent attorneys) and have started and owned a few successful businesses. The last being a 3D prostate ultrasound and targeted biopsy company whose products are all based on my patents. And I'm now i'm in the process of starting a company called Designs for IP which specialized in "patent-centric product development". I also have a fairly strong background in the design and manufacture of motorcycle engines.
JamesDTaylorSTL
Posts: 6
Joined: Wed Apr 13, 2016 6:59 pm

Re: My Classic American Mini-V-Twin

Post by JamesDTaylorSTL »

I just thought you guys might want to see a preliminary pic of one of my (raw) engines mounted in the Franklin Mint 1:5 Harley-Davidson Heritage Softail Classic- Connoisseur's Edition Diecast.

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Man it’s going to look good when finished! Please feel free to pass this along if you know of anyone who might be interested in my engine.

Jim

PS. Here's a detailed review of a very similar (slightly different model) F.M. diecast. This will show you just how incredible that big diecast really is!
http://www.diecast.org/diecast98/html/a ... iewpix.htm
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