View Full Version : V-twin engine (my own design)

02-10-10, 05:31 PM
Several Sundays back I posted some pictures of my latest project for the Sunday build thread. I thought I would start a new thread here with a couple of pictures of my current progress. The complete build series can be found here: A Work In Progress (http://www.homemodelenginemachinist.com/index.php?board=22.0)
The engine has a bore and stroke of 1.00x1.25. The crankcase is aluminum as are the heads. The crank and rods are 1144 stressproof steel. It has a gear oil pump to lube the cams and rods. The crank rides on sealed ball bearings. The valves are stainless steel with bronze guides and steel seats. The pistons have two compression rings. The ignition will have a Hall effect trigger with an electronic spark.

02-10-10, 06:12 PM
Beautiful work George, I always look forward to seeing whats cooking in your shop.

Mario Lucchini
02-11-10, 05:42 AM
This is poetry in metal...............I'm in awe....gringrin

Congrats, George!1clap11clap11clap11clap11clap1


02-11-10, 06:24 AM
Absolutely great work!!!!1clap11clap11clap1 Looks like while the rest of us have been shoveling snow you have been busy in the shop.

Keep up the great work, look forward to seeing this at the NAMES Show.1thumbup1


hot ford coupe
02-11-10, 08:49 PM
This is poetry in metal...............I'm in awe....gringrin

Congrats, George!1clap11clap11clap11clap11clap1


I couldn't have said it any better myself. I wish I could put some good music to it.

02-19-10, 06:05 PM
Gentlemen, here's the latest updates on the V-twin. I bored the hole in the manifold for the carb and then mounted it. That necessitated a couple of pictures. It's actually starting to look like a motorcycle engine now, at least I think so. Next up was some type of airfilter assembly. Although it wont filter air it just adds a nice touch to the engine. I machined the back plate so it would slide on the inlet of the carb and have access to the adjusting screws for the idle and air. The cover was turned and buffed. Afterward I drilled all the holes. I found that by doing it this way it kept the edges of the holes from rounding over with the buffer.

hot ford coupe
02-19-10, 10:10 PM
Beautiful, absolutely beautiful. The talent we have on this site is first rate all the way.

03-02-10, 02:25 PM
Gentlemen, here's an update to show you the progress on the V-twin.
Last year I had built a tubing bender to make pieces for one of my other engines but it was only capable of bending up to 5/16" tubing. The exhaust on the V-twin is 3/8" diameter and on top of that I wanted to make it from stainless steel. This necessitated building another tubing bender with much more sturdiness than the other one. I put about 8 hours into making the new bender.
I have discovered in the past that even with a good bender I would still get somewhat of a flat on the outside wall of the tube. I didn't want this on the exhaust for the twin so I thought I would try out a new technique that I had heard about. I contacted a fellow builder who has much more experience than myself and asked him about it. What's involved is filling the tubing to be bent with a low temperature alloy, Cerrosafe, Cerrobend. The chunk I bought melts at 145 degrees. This supports the tubing and keeps it from distorting.
With a trial piece cut and filled I mounted the new bender into my big vise and with the aid of a 12" adjustable wrench started bending. After bending about 90 degrees I took the piece out of the bender to check it out. Wow, a perfect bend!!! From here it was a matter of cutting all the pieces, filling with alloy, bending, melting the alloy back out, grinding, fitting and finally silver soldering together.
With the large radius on the bender I wasn't able to put two bends close together to try and make the pipe in one piece so I opted to put a small bushing at the joint of the two pieces of pipe. Furthermore, the front pipe would have to pass through the motor mount and I don't know how many tries I would have had to make to get one good pipe.
The first few pictures show the assembling of the front pipe. I turned down a piece of aluminum rod to support the back end of the pipe and locate it to the center of the motor mount hole.

The last pictures show everything polished and assembled. Now it's on to the ignition.

hot ford coupe
03-02-10, 03:18 PM
WOW !!! Now that's what I call replica building for sure. Where can we get that kind of metal and how costly is it? I have a different bending apparatus but it's for smaller tubing and it doesn't make perfect bends. Would you be able to show us the new bender you made? I wouldn't mind taking a crack at that myself.

03-02-10, 06:12 PM
The tubing I used is available from either of the following:
Online Metal Store | Small Quantity Metal Orders | Metal Cutting, Sales & Shipping | Buy Steel, Aluminum, Copper, Brass, Stainless | Metal Product Guides at OnlineMetals.com (http://www.onlinemetals.com/index.cfm)
Speedy Metals Online Industrial Metal Supply (http://www.speedymetals.com/default.aspx)
McMaster-Carr (http://www.mcmaster.com/#stainless-steel/=61qiki)
As far as the tubing bender, I will try and attach a PDF file of the drawing.

hot ford coupe
03-02-10, 07:11 PM
Thanks George. Looks like that'll do it.

03-17-10, 01:39 PM
Gentlemen, well today was the second trial for the new engine. Monday was the first but I ran into a few problems, blown head gasket, a leaky exhaust valve and the starting system needed to be revised. With those things out of the way I went out this morning to give it another try. Success!!!
It just needs some carb adjusting and it should be good to go.


03-18-10, 12:06 AM
Oh Lord...you've got the answer to my nephew's question, while watching my Pochers.....Do they work???

Deeply impressed


12-06-10, 11:07 PM
mercy mercy mercy i congrats u

12-07-10, 07:30 AM
George, Looks and sounds great!!!! Keep up the great work. Ken1gramps1

12-10-10, 08:15 AM

You wouldn't be interested in selling copy's of your tube bender?


01-05-11, 01:13 PM
Hi Doc,
You're more than welcome to a copy of my tubing bender, for free. I have a smaller one that I do most of my small tubing with and then I made a larger special purpose one for just the pipes on the V-twin. Email me off line and I will send you a PDF file of the bender.

01-07-11, 11:52 PM

06-25-11, 02:58 AM
Hey George, you have done a great job, it is awesome work, I appreciate your work, that is beautiful V-twin engine, I like it very much, thanks for sharing a nice pics of your work.

01-21-14, 06:16 PM
Congrats George!

12-11-17, 04:31 PM
I know this is an old thread, but that's just beautiful.

Roger Zimmermann
12-12-17, 05:27 AM
I know this is an old thread, but that's just beautiful.
I agree with you!