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Are the cams the only difference between the TBS and TB engines? I believe the compression ratio is the same, correct?
 

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Isn't there something else other than timing of the valve events? Who knows, maybe the porting is tidied up if the compression ratio is the same.
 

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What accounts for the stated horse power differences?
A balance pipe can have a significant effect on output. Combine that with an aggressive marketing department, and the sky's the limit.

There is no difference in valve timing, ignition timing, carburetion, intake filtering, compression ratio, etc.
 

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Isn't there something else other than timing of the valve events? Who knows, maybe the porting is tidied up if the compression ratio is the same.

Valve timing is the same. I very much doubt that the head is any different. As WSC says, any extra power is down to the exhaust and the marketing people.
 

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also a 6 speed transmission, so gearing could be different making it feel faster, biggest difference is in the handling dept!
 

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The original Thunderbird HP rating was stated in 1995: Mikuni Carbs and the Restricted rubber manifolds between carbs and engine.
We know from NASCAR that restrictor plates limit higher RPM horsepower.

The TBS got the balance pipe, which definately makes a little horsepower.
And the Kehin carbs with the unrestricted rubber manifolds which also makes some HP at higher RPM.

The later Thunderbirds also got the Kehin carbs and the unrestricted manifolds. So they probably actually make a little more HP than the ones with the restricted manifolds.

So it's partially Marketing, and there is some HP at the high end of the rev range. Is that as much HP as the marketing states?
Who knows we would need a brand new TBS, a brand new Thunderbird and a Dyno That's not so likely to happen this long after the fact.

Do some study in the parts manual and you will find all internal parts of all of the classic triples engines are identical.
Some differences in the Sprag clutch.
All TBS do have the 6 speed transmission, Later Thunderbirds have the 6 speed transmission.
All the rest have the 5 speed.

Like TBStunta says the most important difference is the suspension and brakes.
 

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No, that's just wrong. None of the triples uses spin on filter. They all use the same filter inserts. Maybe that filter fits the Thunderbird 1600 twin. (Edit: checked; it does).

BTW, most if not all the filters available in the aftermarket include the wrong large O-ring. Apparently there's a Honda or Kawasaki it also fits, and they use a larger o-ring on the cover.
 

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I though so. Everybody has that wrong now. It's not just K&N. Triumph must have released some bad info. The O-ring cracks me up, I had to order a bag of the O-rings separately from BikeBandit.com just so I don't forget when I change the oil. Got a bunch of crush washers as well. So what actual differences are there between the T-Bird and the TBS?
 

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The rear frame is different. Foot pegs are set back. Forks are different (adjustable) as is the monoshock. Bars and risers are different. Shifter drum rotates in the opposite direction. All TBS's were 6 speeds and final gearing is different. Balance tube in the exhaust. Dual front disks. Rim diameters and tire sizes vary between models.
 

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Also, only the TBS has the cylindrical master cylinders, taller risers, and mnarrower flat bars, the fenders are chopped some and have a raised ridge, the airbox side covers look like a perforated air filter, different headlight ears, seat is different, and the turnsignals are different. Early TBS had aluminum wheels, 2000 and above have chromed steel wheels. Then of course the TBS and Legend have a black powder coated engine.
 

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TBS adjustable peg kit?

You blokes are making me want a TBS, when I know my knees won't like the steeper bend angle!! That's the only reason I'm leaning toward adding a TB to the stable. I have a Tiger800XRx for more 'spirited' riding. I'm just afraid the TB's throttle response will be disappointing in comparison.
So, a question:
Does anyone make an adjustable peg kit for the TBS to reduce the rearward position and knee bend? I know they're available for a lot of newer sport/touring bikes, especially for longer legged's. That would seal the deal for me as the TBS seems like a better bike in every other way.
Thanks.
 
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