Dan's Week 33 Photo Picks: Your Fave Is
- cbxtacy
- Posting God
- Posts: 2543
- Joined: Sun Aug 29, 2004 4:22 am
- Location: San Diego, California, USA
- Location: San Diego, California, USA
-
- ICOA Member
- Posts: 10151
- Joined: Wed Mar 05, 2003 7:55 am
- Location: North East OH, ICOA 3904
Not quite true...Some HDs do have "crossovers" between the exhaust pipes to increase mid-range torque and some of the best performing aftermarket exhausts are 2 into 1s. Biggest "problem" with the Harley market is , the customers want a) looks and b) noise (not sound!)Don #6141 wrote:You don't gain much by running the odd-fire Harley V-Twin into a collector . . . .
Don
There might be some small gain . . . . but when you have an engine with power pulses alternately 315 and then 405 degrees apart, there's no 'tuning' pipe lengths to get both of those to work properly going into the same collector - Not like a 'proper' V-Twin which has a power pulse each and every 360 degrees
Don
Don
-
- ICOA Member
- Posts: 10151
- Joined: Wed Mar 05, 2003 7:55 am
- Location: North East OH, ICOA 3904
A true V-engine by definition has the opposing cylinder rods using the same crankpin. That differentiates a 180 degree V-motor from a Boxer. This being said, the angle between the cylinders has a lot to do with the rotational angle between the power pulses. If you really want 360 degrees between power pulses, you need to have separate crankpins and the angles between these have to be the same as between the cylinders. This may throw your crank out of balance and require serious counterweights.Don #6141 wrote: - Not like a 'proper' V-Twin which has a power pulse each and every 360 degrees
Don
- cbxtacy
- Posting God
- Posts: 2543
- Joined: Sun Aug 29, 2004 4:22 am
- Location: San Diego, California, USA
- Location: San Diego, California, USA
You don't consider the Honda V-Twins to be 'true V-engines'? Yes, it's easy to make a vibration free, even firing 90 degree V-twin . . . . lots of folks have done that. Honda even did it with a 52 degree Vee - Using some engineering (not something you find often on a Harley) instead of big counterweightsEMS wrote:A true V-engine by definition has the opposing cylinder rods using the same crankpin. That differentiates a 180 degree V-motor from a Boxer. This being said, the angle between the cylinders has a lot to do with the rotational angle between the power pulses. If you really want 360 degrees between power pulses, you need to have separate crankpins and the angles between these have to be the same as between the cylinders. This may throw your crank out of balance and require serious counterweights.Don #6141 wrote: - Not like a 'proper' V-Twin which has a power pulse each and every 360 degrees
Don
Only the Shadow ACE used the common crankpin like the Harley's do . . . . and that was only done to make it sound like a Harley - A touch of Honda 'reverse engineering' . . . . or 'anti-engineering', if you prefer. Surely one of the lowest points in an otherwise stellar Honda history
I understand why Harley came out with the single pin crank - Their first V-twin in 1909 was installed on what was essentially a bicycle, with direct drive and no clutch. The engine was the widest part of the bike and making it a 'true' V engine (with separate crankpins) would have made it an inch or two wider, which they did not want
But what I will never understand is why they didn't give each rod it's own throw on the crank when they completely redesigned the entire machine and added a clutch and gearbox in 1926 - The engine wasn't the widest part of the bike by then and going to an even fire engine would have made good sense . . . . but Harley isn't known for that either
A 'modern Harley' (an oxymoron if ever there was one) is still the finest engineering 1909 could produce . . . . which I why you could never sell me one - Gimme a Shadow 1100 any day - No need for rubber motor mounts, your crotch doesn't go to sleep and you can see what's behind you using the MIRRORS!!
Don
-
- ICOA Member
- Posts: 10151
- Joined: Wed Mar 05, 2003 7:55 am
- Location: North East OH, ICOA 3904
I am not judging one over the other. I am just reciting how a V-engine is commonly defined. The reason for building a V-engine is saving space. That's also the reason for the common crankpin. If you don't need to consider space, build a paralell twin or a four. Why did Honda bother to build a V-twin to begin with Why didn't they put a smooth running inline-four into their cruisers? Could it be, that they wanted to ride on the marketing success of HD? Naaah, I don't think so........
-
- Power Poster
- Posts: 271
- Joined: Fri Nov 25, 2005 8:53 pm