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Old 05-20-2009, 12:53 PM   #21
longride
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Originally Posted by Kenneth_Moore View Post
One more explanation and I will be completely lost. Wait, I already am.
Here it is Ken. Normal Vertical Twin motors have an even firing sequence of once every 360 degrees of crank rotation. Every time the crank goes around one cylinder fires and the next time it goes around the other cylinder fires. One cylinder fires at the 0 position for every 360 degrees rotation. If it was a clock, pistons fire alternately at the 12 oclock position

Now, what triumph did here is to stagger the firing sequence to fire at 270 degrees of crank rotation, which means that it will fire at the 0 position and then again at 270 degrees of crank rotation instead of going all the way to back to the 0 position after 360 degrees of crank rotation. If it was a clock one would fire at the 12 oclock position and the other would fire at around 10 oclock.

How's that?
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Old 05-20-2009, 12:57 PM   #22
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Originally Posted by longride View Post
Here it is Ken. Normal Vertical Twin motors have an even firing sequence of once every 360 degrees of crank rotation. Every time the crank goes around one cylinder fires and the next time it goes around the other cylinder fires. One cylinder fires at the 0 position for every 360 degrees rotation. If it was a clock, pistons fire alternately at the 12 oclock position

Now, what triumph did here is to stagger the firing sequence to fire at 270 degrees of crank rotation, which means that it will fire at the 0 position and then again at 270 degrees of crank rotation instead of going all the way to back to the 0 position after 360 degrees of crank rotation. If it was a clock one would fire at the 12 oclock position and the other would fire at around 10 oclock.

How's that?
Ok, I get it. And I think that explains why they need 2 balance shafts and a third vibration damper. They've designed in vibration in their pursuit of a sound. You might say they "Runed" a perfectly good motor.
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Old 05-20-2009, 12:57 PM   #23
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Originally Posted by Kenneth_Moore View Post
One more explanation and I will be completely lost. Wait, I already am.
God says that the only acceptable firing order for a British Twin is 360 degree. Triumph will suffer for their heresy, mark my words! Satanali2 will rain fire and brimstone (and weak American beer) on their heads.
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Old 05-20-2009, 12:58 PM   #24
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think Heretical pop-pop....pop-pop.....pop-pop...pop-pop instead of God-inspired pop-pop-pop-pop-pop-pop-pop-pop-......
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Old 05-20-2009, 01:05 PM   #25
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Originally Posted by longride View Post
Here it is Ken. Normal Vertical Twin motors have an even firing sequence of once every 360 degrees of crank rotation. Every time the crank goes around one cylinder fires and the next time it goes around the other cylinder fires. One cylinder fires at the 0 position for every 360 degrees rotation. If it was a clock, pistons fire alternately at the 12 oclock position

Now, what triumph did here is to stagger the firing sequence to fire at 270 degrees of crank rotation, which means that it will fire at the 0 position and then again at 270 degrees of crank rotation instead of going all the way to back to the 0 position after 360 degrees of crank rotation. If it was a clock one would fire at the 12 oclock position and the other would fire at around 10 oclock.

How's that?
They coulda gotten almost the same sound with a 180 degree configuration and avoided some of the vibration problems.

But where's the fun in that?
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Old 05-20-2009, 01:42 PM   #26
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Sarnali2 needs to learn about the concept of a 4-stroke engine.

0° firing interval is not the same as 360°. 360° is what it is, 360°. No need to make clever remarks.

Left side fires, while the right one has an exhaust stroke, and 360° further, the right one fires while the left one has an exhaust stroke. etc... (with both cylinders on the same crankpin) 0° would be like both firing at the same time. What's the point of that?

270° gives you that off-beat rumbling effect that most cruiser riders like and look for in a cruiser. How dumb would it be to shoot themselves in the foot by not offering it as such? It's not the first triumph to have that configuration. One of the 'new classics' has it as well. The Scrambler. It's just an effort to create a distinctive exhaust note with some individual character.

Lots of hating here, damn...

You say that Triumph already has cruisers, namely the America and Speedmaster. Well, do they sell good? Do they appeal to the average cruiser buyers with only 880cc? etc... It's not for everyone. They're a little too small for me. I'm tall, and I like my bikes watercooled and a little more up to date in the style departement. This thunderbird is more the size and style of cruiser I like.

The Rocket is considered too big. So what do you want then?

Oh, and how many European cruisers can I really choose from? I'm happy they delivered. That discontinued bmw cruiser was fugly. I'm sure as hell not going to buy an overpriced harley in Europe, have you seen the prices?

I happen to think they did a great job on this one. Apart from a few details here and there, it looks really good and well styled. I like the wheels, modern engine, good looking speedo, etc... Motor seems to be a little low on power for a watercooled 1600cc, but it's still more powerfull than the equivalent vulcan 1600 and certainly more powerful than a harley.

It's certainly different and standing out. I'd love to have a cruiser that for a change DOESN'T have a V-twin.

Something almost all of you seem to forget. It's not because they made this bike, that all of a sudden all the other bikes in the line-up will MAGICALLY disappear! Who cares? If it's not for you, get the bonneville, or a harley, or whatever. Lots of brands got 'out of character' models, who cares? Or is the V-rod so well perceived among purists? (or the XR1200)

Oh, and one last thing, there are not an infinte number of ways to design a feet forward, low seat cruiser. It's bound to have a curved teardrop tank, seperate frame, etc... Think about it.

PS: KUDOS to motorcycle.com. BEAUTIFUL photopgrahs in that article!! Nice job

Last edited by euro_biker : 05-20-2009 at 03:12 PM.
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Old 05-20-2009, 02:43 PM   #27
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Looks like a nice alternative for those who want a big cruiser. However once again, this motorcycle is designed from the bottom up and recently too. So why the heck must it weigh over 750 pounds?
Keep in mind this stated weight is a realistic one, not the former bogus dry weights the OEMs used to try to deceive us with. The new Vulc 1700 full-up weight is 761 lbs, so the T-Bird is right in the contemporary ballpark.
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Old 05-20-2009, 02:46 PM   #28
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I have no doubt that Triumph is capable of engineering a good bike. I'm just not sure why they keep chasing this segment. From the Bonneville America to the Rocket 3 have any of their cruisers done well in terms of sales volume?
To be in the cruiser market without a bike in the range of 900cc to 2200cc doesn't make sense. Hence the T-Bird.
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Old 05-20-2009, 02:50 PM   #29
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The old T-bird sport (triple with twin mufflers on one side) looked to be my kind of bike.
Me, too. But they didn't sell. This new one, even in a crappy economy, will do much bigger volume. It's not the Triumph of old, and that includes a continuing success. Triumph has doubled its market share since 2005, and it now exceeds Ducati in volume, so they are doing many things right.
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Old 05-20-2009, 02:57 PM   #30
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Keep in mind this stated weight is a realistic one, not the former bogus dry weights the OEMs used to try to deceive us with. The new Vulc 1700 full-up weight is 761 lbs, so the T-Bird is right in the contemporary ballpark.
I think his question is somewhat in-line with my own thoughts on this - as in WTF does any motorcycle weigh-in at 750 pounds?

Hell, the F'n BossHoss weighs only about 250lbs more, and they use a F'n cast-iron-block automotive V-8 as the "core" of the F'n thing.
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