jayel
#9 Guru 74 TX650A
wow I like it http://www.bikeexif.com/
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McGyver62
McGyver62
several really cool bikes at that linc
Highside
Lord of the Flies
The Harley that thought it was a Triumph...
Real nice
JAGUARGOD
XS650 Addict
That dude did it right...love it!
MTcycle
MTcycle
Looks like the back cylinder might get hotter than the front one. Not sure it's the best design for a reliable bike? The Triumph is cool.
jayel
#9 Guru 74 TX650A
well after 108 years of continuous operation (oldest motorcycle company in the world) I think they have that figured out
when Honda & other Japanese Co.s came out with the tranverse fours it was the end of the Vee-twin (except for all the Vee-twins the Japanese now make) 
MTcycle
MTcycle
Millions of oil stained garage floors can't be wrong!
Kingwj
I know nothing, nothing!
MTcycle
MTcycle
Capt_Zoom
Raider Rider/xs newbie
LOL
CDNTX650
XS650 Guru
you live under a rock or what, like someone said over 100 years with about 7 motor changes....surely the design works.
MTcycle
MTcycle
In re reading my post, I think I said "not sure it's the best design". See many Ariel square 4's out there? Neat bike, but the back cylinders ran hot and sank it. All the Asian v twins run radiators. Doesn't the Minnesota bike run a radiator? I'll take a parallel twin air cooled bike under my rock any day!
1974jh5
Curmudgeon.
Harleys are known for having problems with the rear cylinder before the front one. That engine is loaded with basic design flaws. (ducks oncoming rain of bricks and broken bottles)
The reason the Harley engine was designed that way back in 1903 was to make it narrow. The cylinders being in line rather than offset contribute to the rear cylinder overheating, it gets all the hot air off of the front cylinder rather than a nice cool breeze.
The 45 degree 'vee' is so narrow at the base that it's difficult to get a decent bore/stroke ratio which is its biggest limiting factor, right behind that is the connecting rod length. Then the 'knife/fork' connecting rods on a single crankpin make for a weak assembly. The three combined limit the latest version of the motor to around 6000 RPM which severely limits its maximum power output. The basic limitations of the 45 degree V make overhead cams useless, that's why it still uses pushrods.
You have to pump a lot of air through an engine to make HP, one way is more displacement. But that's limited by volumetric efficiency. The other way is to turn more RPM, that is not so dependent on displacement or VE. Since the Harley can't turn the RPM needed, it can't make the HP it should for its displacement.
That basic design limitation is why Ducati built their V twin the way they did (actually it's an L design, 90 degrees) and it's why the same displacement Duc powerplant will make a BUNCH more HP than the Harley, like 150 HP at 9250 RPM compared to the Harley's 68 HP at 3500 with a 5500 redline. IMHO a Duc's dry clutch rattle and idle sounds a lot better than 'potato potato potato' too. Crap, a stock antiquated XS650 makes, what, 45 HP at the rear wheel? If it was 1200cc then it whould make probably around 80, still way ahead of the Harley.
The V-Rod's Revolution 60 degree motor will rev to about 9K, still not much compared to other similar displacement engines. But that change in the basic architecture allows it to make ~120 HP.
The reason the Harley engine was designed that way back in 1903 was to make it narrow. The cylinders being in line rather than offset contribute to the rear cylinder overheating, it gets all the hot air off of the front cylinder rather than a nice cool breeze.
The 45 degree 'vee' is so narrow at the base that it's difficult to get a decent bore/stroke ratio which is its biggest limiting factor, right behind that is the connecting rod length. Then the 'knife/fork' connecting rods on a single crankpin make for a weak assembly. The three combined limit the latest version of the motor to around 6000 RPM which severely limits its maximum power output. The basic limitations of the 45 degree V make overhead cams useless, that's why it still uses pushrods.
You have to pump a lot of air through an engine to make HP, one way is more displacement. But that's limited by volumetric efficiency. The other way is to turn more RPM, that is not so dependent on displacement or VE. Since the Harley can't turn the RPM needed, it can't make the HP it should for its displacement.
That basic design limitation is why Ducati built their V twin the way they did (actually it's an L design, 90 degrees) and it's why the same displacement Duc powerplant will make a BUNCH more HP than the Harley, like 150 HP at 9250 RPM compared to the Harley's 68 HP at 3500 with a 5500 redline. IMHO a Duc's dry clutch rattle and idle sounds a lot better than 'potato potato potato' too.
Crap, a stock antiquated XS650 makes, what, 45 HP at the rear wheel? If it was 1200cc then it whould make probably around 80, still way ahead of the Harley.The V-Rod's Revolution 60 degree motor will rev to about 9K, still not much compared to other similar displacement engines. But that change in the basic architecture allows it to make ~120 HP.
