Ellery V-Twin 100cc Design & Build

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I join in, I am also enthusiastic about the work on the engine.
When everything is finished, I would also like to acquire a drawing.
Bravo, you did a great job, where is it possible to buy the project to build this engine?
Well it feels like an age since of worked on this. Think I lost a bit of interest and needed to work on other things. But there is not actually that much more to get this finished and so hope to get this finished over the next few months.

Today I did some heat treatment of silver steel parts. Rocker arm, rocker pin, and tappets. Got some fire bricks after learning the hard way last time and getting spat at by exploding brick. Heated parts to deep red then quenched in some light oil. I then tempered in an enclosed BBQ at around 250°C for 30-40mins.
I've now way of knowing if the process has done what it should have, guess I will find out if the parts wear or break.


I also started making rings for piston 1 ( I have a slight difference is size between cylinders). I know there are probably better ways to do the rings, but I used what I think is the simplest method. ID and OD of ring to match the depth of slot in piston, and ID of bore respectively. Part off about 0.03mm over width. Sand and polish to fit snug in slot using 600 then 1200 grit on a flat piece of glass. Snap the ring in vice with a crisp knock with a chisel. Hold in an expanded condition and heat until it relaxes into that position and drops.

Congratulations again for the outstanding work,
can i know where i can buy the project?
Congratulations again for the outstanding work,
can i know where i can buy the project?
Thanks Spotter. Not sure if I will release the drawings, some of which are a bit of a mess now. Also i'd want to make sure it actually works first :)
Your ring making technique is exactly the way I do it. I have found that when I make the piston (only cast iron of course), I make the piston longer, and after turning to diameter, turn the last section to the OD of the ring groove depth. I then use a very narrow fiber dremel grinding/cutting disc in my dremel tool mounted to the tool post, and cut the rings off the end of the piston.

I used to break the rings as you do, but found that cutting them with the same dremel cutting disc makes the edge straight and smooth, which makes them drop off the section of rod smoothly when hardening and setting the spring.

Since the edges are already cut smooth from the dremel/lathe cut off operation, it just takes a little polishing with some very fine paper on the edges and done!
Hi cbooth. I sure hope you decide to offer the plans. Great Project! I would like to build this one😊😊
Here's a bit on the cam profiles.
I've been using a "Cam with draw" excel spreadsheet that someone has very nicely shared, to work out a cam profile.

I have drawn this in cad to work out the crank to cam relationships.
So I have a total working angle of 135° for each lobe. The exhaust leads the inlet by 105°, and there is a 30° overlap.
Cylinder 2 will be offset by 135° (cam angle)
Well, got the cam made. used the mill, and happy with the results, EXCEPT i've got the cylinder 2 lobes at the wrong angles. 😢😭
Not a machining error, a drawing error...so thats for the junk bin, and start again. Fortunately have just enough silver steel for another go
thanks guys. Made a new cam blank and i'm now ready to machine the lobes again.

I have now also made all the individual sections for the inlet from stainless steel, ready for silver soldering together. My silver soldering ability leaves a lot to be desired so will need to practice first.


Started to get the get the engine mount box with ignition, battery, and fuel tank ready. Will also add a servo for the throttle control.
:):):)Very happy today. Got the engine running, and it started pretty much first attempt. I only ran it for a few minutes and did not attempt to rev it. Unfortunately the tacho was not working (found a loose wire) so I didn't get a reading.
I was thinking it may need a fuel pump, but it seemed to draw the fuel through without even the crankcase pressure tube connected.
I plan now to strip it back and double check everything, then start on tuning it as I did not even attempt to adjust the carb needles today.
Link to video below:
Video of first run
Fantastic! Sounds great, ran fine - when I read that part about adjusting the carb needles, I expected it to run at the same RPM for the video, but it sounded like you were able to throttle it up and down.

This engine is an inspiration. Looks beautiful, runs great, sounds great, it's the real deal!