Dear MOby,

Excuse the noob question, but what’s the difference between a transverse V-Twin and a longitudinal one, and what are the advantages of each?

Navigational Ade


Dear Ade,

It has to do with the orientation of the crankshaft. Any engine, be it a V-Twin, V-Four, or inline-Four, is considered to be “transverse” if its crankshaft lies perpendicular to the motorcycle’s wheels, i.e. across the frame, parallel to the axles. Most motorcycles have transversely mounted cranks, including all Harley-Davidson V-Twins, nearly all four-cylinder sportbikes like the Yamaha R1, Kawasaki ZX-10R, Aprilia RSV4, all Ducati V-Twins and V-Fours… including the Monster 797 pictured on the left, above.

Chain or belt drive to the bike’s rear wheel is simplest and lightest with this layout, and having the crankshaft spinning in the same plane as the rear wheel means power can be transferred through the gearbox and straight on into the drive chain and rear sprocket without making any power-sucking changes of direction.

transverse crankshaft diagram

Your basic transverse crankshaft, i.e., crankshaft parallel with wheel axles.

I can’t think of any modern racebike that doesn’t use a transverse crankshaft and chain final drive: It’s simple, efficient, light and allows easy sprocket changes to alter gearing for different tracks. The downside is that drive chains and sprockets require maintenance and wear out (a lot less quickly now than before the invention of the sealed O-ring chain).

Chain reliability in the bad old days is why many touring bikes, especially ones that have been around awhile, have longitudinal-crankshaft engines that use a shaft drive to send power to the rear wheel, like an automobile.

BMW boxer diagram, longitudinal crankshaft

BMW Boxer Twins have used this layout for nearly 100 years now: The crankshaft spins in the same plane as the driveshaft, and the one 90-degree turn as the driveshaft feeds power to the rear wheel is nearly as efficient as a chain but requires no maintenance (unless something goes wrong…).

The Honda Gold Wing’s six-cylinder Boxer motors also use a longitudinal crank and driveshaft, as well as the defunct Honda ST1300. So do all Moto Guzzis, including the V7 in the right half of the lead image, and so did plenty of vintage bikes. Riders who pack on plenty of miles and don’t want to be bothered to oil their chain, or toss and turn at night worrying about what lube to use, have always been fans of shaft-driven bikes.

Not to say that there aren’t plenty of bikes with transverse cranks and shaft drives, like the Yamaha FJR1300, BMW K1200/1300 series bikes and now the K1600 Six-cylinders. All those bikes must redirect power through two 90-degree bends to get it to the rear wheel, which costs weight and a little bit of power, but those aren’t critical commodities on big touring bikes.

One final thought: Don’t be confused by Moto Guzzi, which totally goes its own way as usual by calling its bikes Transverse Twins in its spec sheets. Those cylinders jutting out on both sides are transverse maybe, but Guzzis all have longitudinal crankshafts passing power into their shaft final drives.

Other advantages and disadvantages of transverse vs. longitudinal could fill more than one book, and have – but these are the basics.


Recent Ask MOs:
Harley-Davidson Roadster or Triumph Bobber?
Why Does My Motorcycle Clunk When I Shift Into First Gear?
Variable Intake Velocity

Send your questions to AskMoAnything@motorcycle.com. Questions are answered by volume, not by weight. Some settling of your answer may occur during shipping and handling. Not responsible for lost or stolen answers, and definitely not responsible for wrong answers, though we’re happy to take the credit if we’re right.

  • Kenneth

    A good question, and a simple-but-thorough and nicely illustrated description of the two engine/crank orientations. It bugs me (just a little) when someone calls a Guzzi or BMW boxer engine “transverse” or a Harley, “longitudinal.” Whew, now those days are over… right?

  • Deryl Clark

    As the owner of a ST and a Griso I must quote Elvis and say
    Thank You……..Thank You Very Much.

  • CLARITY

    On the transverse engine the clutch is easy to access from the side. Not easy on the boxer type engine or the Guzzi..Your picture does not even show it.No one ever tells you until service time.You can still have shaft drive with longitudinal engines.Adding one more worm gear is no big deal.

    • Doug Ritchie

      Maybe easier to access, but longitudinal motors have automobile style clutches and have long service lives. My Stelvio’s clutch currently has 83000 miles on it and is still going strong. I expect to get 100,000 out of it and for me, doing a clutch every 100,000 miles is not a big deal.

      • CLARITY

        Thanks for your insight ,i did not know they were dry clutches and about their longevity.

        • Clutchman11

          I’ve got a wet clutch in my 1997 Honda Africa Twin (XRV750RD07A). Still original and with more than 180,000km (113,000 miles approx) and no slippage. And that is with multiple trips into the Sahara, regular trips into the Alps and Dolomites.

  • Steve McLaughlin

    When they mount and engine in a supercar, it is called “oh” transverse. When you put an engine in an Moto Guzzi (my favorite), it is also “transvers”. regardless how the drive shaft goes. What about those “complicated” drive shaft systems in some bikes? Is that a “complicated” engine description?