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Just read this over at the harley forums. Appears the engine will keep 90 degrees between pistons but will rotated towards the rear making it a true vtwin.

http://www.hdforums.com/forum/off-topic ... f-you.html

LOL at the post after yours.

The guy is talking about the bevel drive Ducatis and calling it the Desmo.

I just love the look of the air cooled L-Twin behind the tubular steel trellis frame, especially the older delicate looking frame like on my 900 Supersport.

Ummm first off Hyperr you're completely right, that guy has no idea what the Desmodromic valve system is.

Secondly it still will be an L-twin. HD has the patent on what is an actual V-twin. All of the other 2 cylinder configurations with an angle between the pistons (other than 180 and 360 obviously) are technically V-2s. Harley has the V-twin because it uses the same rod bearing for both connecting rods.
On the Harley one of the con-rods is actually nestled in between the split end of the other.


On other crankshafts, it's two separate rod bearings that they're on, so the jugs are actually slightly offset.

Wrider wrote:HD has the patent on what is an actual V-twin.

Wrider, is this a fact or an old Harley wive's tale?

Haven't looked up the actual patent but pretty sure it's a fact.

Besides it's a pretty efficient design if you're not going for high performance, so I'm sure it'd have been copied by others by now if it wasn't patented.

Wrider wrote:Haven't looked up the actual patent but pretty sure it's a fact.

Besides it's a pretty efficient design if you're not going for high performance, so I'm sure it'd have been copied by others by now if it wasn't patented.

As with most motorcycle companies, they have many patents on their engine design but I don't think they have a patent or trademark on the name V-Twin...but I could be wrong.

I don't think the design is good functionally anymore. It was designed long long ago when they didn't know any better. The only reason they kept it is because the two big jugs thundering up and down together creates that certain Harley Davidson sound, vibration, and feel. Harley could easily design a much better functioning V-Twin if they wanted to but chooses not to as this is what their customers want.

I'm pretty sure Harley doesn't have a patent on the forked rods, there were other manufacturers that used the design back in the day. Harley isn't the only one to use a 45° spread for the cylinders, they can't patent that part of their design either. S&S builds any type, design, and/or configuration of a Harley engine you want so what exactly can they patent.

Johnj wrote:I'm pretty sure Harley doesn't have a patent on the forked rods, there were other manufacturers that used the design back in the day. Harley isn't the only one to use a 45° spread for the cylinders, they can't patent that part of their design either.

Not that any of this would ever stop the Harley corporate lawyers from trying.

HYPERR wrote:LOL at the post after yours.

The guy is talking about the bevel drive Ducatis and calling it the Desmo.

It's late, I'm tired, but what am I missing here? The bevel drive twins were desmos.....

Oh no I never meant the name v-twin. I meant the crankshaft configuration that is referred to as a v-twin.

And you're right that wouldn't stop them from trying... A few years ago they actually tried to patent the sound that their engine makes...

And JohnJ I'm not sure, that argument came to mind as well, but keep in mind that a patent owner can agree to allow another company to use it's patents in exchange for a royalty fee.

Highside, yes they were Desmos, but so are the modern ones, the Desmo refers to the valves being opened AND closed by followers on camshafts in the top end of the engine instead of using valve springs...