What's the difference between three cyclinders and four...

[reddeviljp]

Brought up in a bike loving family I was always led to believe that the four-cylinder bike was the ultimate bike and anything less was inferior. Now, with the success of the Street Triple and the impending MT-09 I'm being told that three cyclinders are the dogs bollocks and superior to the four? What's changed?

What's the reason for all the praise for three cylinders?
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Bike: 1993 CB400 SuperFour - 1999 Yamaha FZS600 - DAS passed 7/11/13 - Working my way towards a Yamaha FZ1.

[Wafer_Thin_Ham]

Nothing really.

An IL4 is still the idea package of width, cooling, economy, and power.

Triumph used it more as a USP than anything else, found it worked well with the gearing/whole package, and now a few others have picked it up and ran with it.

Now some are saying ZOMG tripelsss are amazaballss!!111

If Triples are so great, why are all moto GP bikes 4 cylinders, and why was the last bike to win WSS an IL4?

TLDR, there's no "perfect" cylinder configuration.
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[Pete.]

"What's the difference between three cyclinders and four..."

One cylinder.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[Nobby the Bastard]

Narrower engine.
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trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050

[Wafer_Thin_Ham]

[Nobby the Bastard]

[Wafer_Thin_Ham]

[Wafer_Thin_Ham]

[Nobby the Bastard]

[Pete.]

[Wafer_Thin_Ham]

[Nobby the Bastard]

[Nobby the Bastard]

[Wafer_Thin_Ham]

[Nobby the Bastard]

As a final comment, there are 2 bikes that have a reputation (aside from the run of the mill 4 in-line bikes like the R1, Fireblade etc.) of being absolutely insane. I'd love to ride one. I know someone who owns one of the pair and at some point I'll pursuade him to let me have a go.

Most of them were written off.

They are the Kawasaki H1 and the Laverda Jota.

Both were triples.
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trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050

[Vincent]

120 degree tripples sound better than IL4s...........er.. imo of course.
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[Wafer_Thin_Ham]

[Wafer_Thin_Ham]

[MarJay]

Lots of engineers believe there are two ideal engine configurations from the point of view of packaging on a motorcycle. The ideal configuration isn't too wide (like an IL4 can be) or too tall (Like a V twin nearly always is).

Honda believe that the V4 is the ideal configuration due to it meeting the above requirements. However, it's a pain in the butt from an intake and exhaust point of view, and rear cylinder cooling has always been an issue.

On the other hand, Aprilia created a 3 cylinder GP bike as their first four stroke MotoGP bike, the RS3 cube. This was basically a formula 1 V10 with 7 of the cylinders lopped off. This is because a number of automotive engineers believe there is an ideal cylinder capacity which happens to be an approximate 330-350cc value. In a triple this meets the 990cc original rules for MotoGP, and can also build a 3500cc V10.

A triple is not too wide, nor too tall, and doesn't have any problem with intake or exhaust location. It can be tuned for bottom end torque or top end power just like a V twin and a four. It's cheaper to manufacture than a four cylinder, and is waay cheaper than a complex V4. In the right crank configuration it has a good primary balance, and a decent secondary balance.

Triples are good engines. Yamaha is going to triples because it can't compete with the other Japanese bikes any other way. It wants to differentiate itself from the other japs. In doing so it found that it could make a good triple. Funnily enough, Yamaha have a history with triple engines anyway, so it's not entirely unprecedented. It's also an easy way to give an engine 'character' whilst still being able to make it reasonably powerful and have reasonable bottom end.
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British beauty: Triumph Street Triple R; Loony stroker: KR1S; Track fun: GSXR750 L1; Commuter Missile: GSX-S1000F; Cheap project: CBR900RR FireBlade
Remember kids, bikes aren't like lego. You can't easily take a part from one bike and then fit it to another.

[Nobby the Bastard]

[MarJay]

[Nobby the Bastard]

[MarJay]

[Islander]

[Ariel Badger]

You can't beat the raw power of a big single, be it my Badger or an MT03.
It is like sex, if you like it dirty, sweaty and brutal without a condom you should not ride a multi.
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Bikers make great organ donors, get 115 on your licence today.