100cc Villiers

Was getting my bikes out for the upcoming move. This bike hasnt seen the light of day for years. Thought I take a few pics. The build is basically finished, just a million little details. The Villiers is driving thru the bottom bracket directly to a clutch on the right side to a 3sp IGH.
I did something I have wanted to do but have never done, is to convert a coaster wheel to a front brake. Notice also where the rear brakes are. Should be a cool old school ride. Its a true 100cc. The old Villiers are smooth, torquey runners that dont rev overly high. The engine is an early 30s and the frame is a 36 Cleveland Welding step thru.This one may reach forty. Will be badly under braked at that speed, will keep it as an easy going 30ish cruiser.

 

[Cannonball3]

Some peeks into the mag. Our brothers from the UK certainly march to different engineering drums
than we do. Look closely at the points. You break loose a lock nut and wrench the fixed point up/down to adjust the gap then relock! There the Joseph Lucas prince of darkness coil. Im assuming the condenser is in the round thing under the points or maybe the whole thing is the condenser?

Certainly looks like a cycle cylinder to me. Must be obscenely powerful as it has triple Xs cast into the base. I dont think I have ever seen a bigger magneto just to make spark for such a small engine! Plug is a 2 piece take apart triple sparker Lodge made in England.
This thing is a trip down Eclectic Ave!

 

[DieselTech]

Thanks Nick!

Always repurposing things. Have a massive junk box of stuff. Generally find something in there to use.

I cannot find this particular model of engine in all the internet. It has a CYC prefix to the serial # which according to sources makes it a 1936, possibly used on some cycle. There are plenty of Midget engines out there, I have looked a zillion, but none have this cylinder. Has a long straight in intake, central spark plug and a large finned curved exhaust.
Doesnt really matter I guess just got my curiosity up.

C1936 atco lightweight, vertical midget villiers engine. CYC referred to a centrally located spark plug, straight intake, no decompression valve, & a few other things. Basically I think it was how the engine was configured.

 

[Nickt919]

……I cannot find this particular model of engine in all the internet. It has a CYC prefix to the serial # which according to sources makes it a 1936, possibly used on some cycle. There are plenty of Midget engines out there, I have looked a zillion, but none have this cylinder. Has a long straight in intake, central spark plug and a large finned curved exhaust.
Doesnt really matter I guess just got my curiosity up.

All the old stuff you show… I’m seeing it for the first time.

I’m not sure how common those old engines are but my limited knowledge….I didn’t know they existed.

They’re very cool to learn about.

 

[DieselTech]

Also what did the UK refer to as a midget, my idea of a midget is a 1/4 midget with either a small block or a motorcycle engine. & I sure know they were not racing midgets in 1936. So what the heck was the UK referring to when they say midget engine? Thanks

 

[Cannonball3]

So after a bit of cleaning its a CYZ. Heres something that tells about the M/C use. They were use on bottom end depression (in England) motorcycles. The one in the pic is similar but still a bit different. It is what it is as they say, hopefully it will soldier on awhile longer, seems like it wants too. I started my wrenching career working on English sports cars, and this thing is a blast from the odd engineering past.

 

[Cannonball3]

Theres an interesting thing about this engine and a lot of the Villiers in general. This engine has the intake port in the normal rear of the cylinder location, but the exhaust port on the side. Some had the ports opposed. Also they made versions of the M/C engines with twin exhaust ports very early on. They appeared to be master casters of single piece jugs.

 

[Cannonball3]

Heres a pic of how simple and adaptable this engine is. Just a crankcase and cylinder basically. Fits about anything one can make mounts for. They thoughtfully included a drain plug for easy oil changes.

 

[Cannonball3]

So got into running the Villiers, but just couldnt get it to run well. Started and idled easily. But had no power. Then it dawned on me. Pulled it down and sure enough plugged exhaust ports. Don't know how it ran at all with that tiny bit of port opening! Its definitely prewar. Pretty archaic in design. Its a total bushing engine save for rollers on the rods big end. Doesnt even have crank seals. Ramped piston, with massive rings. Stoutly built though, and shows little real wear. Cool thing is the flywheel nut is its own flywheel puller.

 

[Cannonball3]

Some preliminary cleaning of the ports, should be happier now. Hole in cylinder is the transfer port! Crank is symmetrical can run it either way I guess. The strange groove in the case appears to route oil to the bushings but its not drilled thru, besides the oiling grooves arent aligned anyway. The Maytag uses an Archimedes wheel to do the same thing.

 

[Cannonball3]

A few more interesting facts. The piston is ferrous, cast iron I assume. Its bushed with bronze. The wrist pin
is buttoned on one side only, its caged on the other side. Check the mag, its huge. Compare that to a CGs mag.
This engine is square 50mm bore, 50mm stroke for 98cc. Its extremely well built and its engineering is quite good
now that I have had hands on. I actually made a carb needle from an NT to replace the missing one and it worked!
I believe the crank bushings were intentionally at some point installed 180 away from the oiling holes probably to cut down on oil loss from both sides of the crank. The mag actually has a weep hole to keep oil out of it.