Triumphrat

Simmo

Aussiebikerdave has a srambler that he has hot rodded. It makes the hair on the back of your neck really stand to attention when under power, amazing.

270 deg vertical twins sound like a 90 deg twin not a 45 deg twin. A 270 Triumph with compression and cams sounds quite similar to a Ducati or VTR Honda. A standard scram with TOR's make a racket, fun but noisy.

Cheers, simmo

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Ride it while you can.

TerryK

Agreed, I've taken my TORs off the Scrambler, way too noisy

Terry

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Blue & White Scrambler, Staintunes, Dart flyscreen
Red Thruxton, Staintunes, flyscreen
TT-R250RA, Staintune, B&B bashplate

Askari

A 180 twin gives good primary balance one up one down.
A 360 is just a big single with all going up and down together, the advantage over a single is you get 2 pulses.
A 270 has an advantge over the 360 in the torque department as the pistons are never stationary as they are in a 360, this is the same as in V twins hence the comparisons with harleys.
A 270 will be smoother than a 360 unless balance shafts are used but this is irrelavant in this thread.
There were quite a lot of meridan era 270 deg twins nice and easy with 2 bearings.
Couple of stiff drinks, hacksaw, some V blocks, a protractor and a welder!
Just to stir up an old thread a 180 deg motor has a lot less pumping loses than a 360 deg motor.
As to the triple, please clarify. The most sublime triple sound was the 180 deg Laverda Jota, the later 120 deg motors were well like flat warm beer in the Aus outback!

Simmo

Yup the 180 deg Laverda triples are in a class of their own. From what I can remember of them the 120 deg crank models never really sounded that good or went that well. My Sprints and the various Triumph triples have all sounded better. Maybe the first gen with twin mufflers sounded the gruffest.

Time for a soothing ale. Wish it were a bit warmer though.

Simmo

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Ride it while you can.

mikeinva

if you think about it a 360 is about like a 2 stroke single.a 360 goes bang bang a 270 you get bang bang then a pause bang bang .the pause is why they hook up better on dirt.both will have near the same torque at the same rpm with everything else the same such as cams.how you feel the torque will be slightly different though.
If you have ever run a old jonhdeer thumper tractor you can watch the back wheel when it fires try and spin the wheel then there is a pause then it fires again .They will pull things in soft ground that other tractors with more hp wont because of this a 270 kinda does the same thing.It lets the tire bite before it hits it again.

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Why do I feel young on my bike

Askari

Mike is right there will always be a smoother, seamless, steam engine like delivery, with a 270. Till you turn of the key there is always a piston on the move, with a 360 they are both stationary at TDC and BDC. When a piston is at these points on a 270 the other piston is moving.
An example of this would be in heavy haulage. When there are multiple ballasted prime movers pushing and pulling a load. I asked a friend who is involved in this about synchronising gear shifts. As he pointed out you dont. Reason if everyone changed at the same time the load would stop. So it is always good to have a bit of momentum still happening.

bobbo

Compression is 9.2:1 for all bar the Thruxton, which has the higher compression you mentioned

mikeinva

all of them had 9.2 up to when the efi bikes came out even the thrux .I dont know what the efi bikes have but would not suprize me if they are all the same .triumph has allways tended to bend the truth on the thrux motors to make people think there better when truth be known they had the same motor the thurx had better headers thats all.

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Why do I feel young on my bike