vintage motorcycle engines?

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GlennW
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Location: Florida

Re: vintage motorcycle engines?

Post by GlennW »

One of the first internal combustion engines built. Single cylinder Daimler.

Hot tube ingnition. The small reservoir behind the saddle contains the fuel (I believe it was Benzolene) to sustain a torch flame to heat the tube.

I believe it also had a fuel system where the Benzolene was "percolated" and then engine ingested the vapor.
Glenn

Operating machines is perfectly safe......until you forget how dangerous it really is!
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ken572
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Re: vintage motorcycle engines?

Post by ken572 »

Glenn,

Very Cool. :wink:

Thanks for sharing.

Ken. :)
One must remember.
The best learning experiences come
from working with the older Masters.
Ken.
Doug4d3s
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Location: St Louis MO, USA

Re: vintage motorcycle engines?

Post by Doug4d3s »

alphawolf45 wrote:
Doug4d3s wrote:...As for legal or not, well some of those small ones are no more than mopeds that do not require registration in some states.....My concern would be for safety since strictly vintage replica would be slow to accelerate by today's standards and no turn signals and inefficient brakes ...
I'd think you could improve a lot on the power & performance and still have something that looked pretty authentic. The ancient engines did a lot of odd things like unactivated intake valves and multiple exhaust porting that nobody has done in 90+ years. A ~1925 board-track racing motorcycle had a ~1000cc engine that only made about 8 HP, while a modern Harley 883cc engine puts out 55HP. I would be willing to bet that one could easily build an 800-1000cc engine that would put out at least 15 HP just by following common modern engine design practices. That's in the area of what a ~200cc modern scooter has, and that's about twice as much power as any of the ancients had.

You also wouldn't need to scratch-build every single engine part. You'd save a lot of time & hassle just by using maybe the internal pieces from a Harley 883cc engine--the crank, con rods, pistons, valves and so on. Plus when they wore out, you wouldn't be stuck DIY-ing new ones yourself..... All you'd make is the visible parts like the engine casing, cylinders, cylinder heads (I'm sure this is way more work than I am pretending it is ;) ).... Nobody is going to care if the inside parts aren't exact copies, and (if you're like most of us) you probably can't forge a decent crankshaft at home to save your life anyway.

If you wanted to get fancy you could convert the Harley-883 pieces to an external valve-train. An exposed valve-train would make the engine look VERY authentic, but (if you read about any modern rally enthusiast meets) it would also bring along a lot of attendant maintenance & reliability issues. Motorcycles and cars had exposed valve trains up until about 1925, when they all went internal and never looked back. I think that big ship engines are the only ones left that still use them, and ship engines run in a much cleaner environment than a motorcycle engine does.
......
Maybe you could do a flathead engine, and make "fake" OHV valve lifters that move?
gbritnell
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Re: vintage motorcycle engines?

Post by gbritnell »

Not in the full sized category but I designed and built my own motorcycle type engine. It's a 90 degree, air cooled, pressure oiled, overhead valve engine. I see no reason why a good machinist couldn't build a full size version. The limiting factor would be the size of equipment that a person has available and the skill I guess. With so many scrap motorcycle parts available today, transmission gears, valves, carbs etc. it would be an easier job to incorporate some of these parts into a build. That way you'd have properly heat treated gears and such to work with.
Here's a few pictures of the engine I designed and built.
gbritnell
http://youtu.be/opvp1sGQtJU
Attachments
GQ.jpg
OD.jpg
OH.jpg
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Harold_V
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Re: vintage motorcycle engines?

Post by Harold_V »

gbritnell wrote:Not in the full sized category but I designed and built my own motorcycle type engine. It's a 90 degree, air cooled, pressure oiled, overhead valve engine. I see no reason why a good machinist couldn't build a full size version. The limiting factor would be the size of equipment that a person has available and the skill I guess.
Exactly! One must keep in mind, it was other people that built those that exist.

Beautiful model. I'm amazed at how quickly it starts.

Well done!

Harold
Wise people talk because they have something to say. Fools talk because they have to say something.
Bruce
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Location: Los Angeles, CA

Re: vintage motorcycle engines?

Post by Bruce »

gbritnell, Thanks for the pix. I saw your engine on youtube before starting this thread: very nice work! I have decided to use the crank, rods, valves, piston and carb from a modern engine for my build and that's how I would deterimine displacement, bore etc. Based on the look of the vintage engines however, it appears as though they have a rather long stroke considering the diameter of the crankcase and the length of the cylinders. I'm not sure but I might need to make longer rods to get that vintage look. Does anyone have any input on this?

Bruce
JackF
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Re: vintage motorcycle engines?

Post by JackF »

gbritnell,
That is some beautiful work. What is the approximate scale of the engine?

Jack.
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ken572
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Re: vintage motorcycle engines?

Post by ken572 »

Bruce,

Go here:

http://www.archive.org/details/Tm9-879HarleyWla

Click on .pdf on left side and download. (Out of Copyright) :mrgreen:

Ken. :)
One must remember.
The best learning experiences come
from working with the older Masters.
Ken.
Bruce
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Location: Los Angeles, CA

Re: vintage motorcycle engines?

Post by Bruce »

Thanks Ken. That is a great site!
gbritnell
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Joined: Sun Feb 20, 2011 10:07 am

Re: vintage motorcycle engines?

Post by gbritnell »

Hi Jack,
It's not really scaled from anything in particular. The bore is 1.00 and the stoke is 1.25. I would say if it were scaled from something is would be about 1/4 scale.
gbritnell
JackF
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Location: Caldwell, Idaho

Re: vintage motorcycle engines?

Post by JackF »

Thanks gbritnell,
Not that I have any immediate plans to make a scale model bike engine at this time but after I finish with the hot rod my first desire is to make a model Flat Head V 8 and then a Model Harley Flat Head 45º V twin. :D I should live so long. :shock: :roll: :lol:

Jack.
Bruce
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Location: Los Angeles, CA

Re: vintage motorcycle engines?

Post by Bruce »

Jack check out you tube videos of "model V twin engines, there is a panhead, a knucklehead, and a flathead and more.

Bruce
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