how come Harley don't make shaft driven?

Question

i find it more reliable.

Answer 1

For all the haters:
Belt drive is extremely reliable, what maintenance do they need, none!
Whether you like American, Japanese, or Italian ( the one hold out is BMW) The cheapest bikes from the Japanese Harley clones have chains. The middle ones have shaft drive. The big expensive ones have belt drive, must be a reason.
Belt drive is a fantastic option for delivering power to the rear wheel without rear lift, tourqing, and loss of power.
They are also reliable and maintenance free. They never need to be oiled and the newer belts last forever.
More powerful custom cruiser/choppers do need a chain, as do sportbikes, as a belt can break if overpowered. Chain is definetly the most effective for power, but they do require maintenence.
You will notice none of the best sportbikes have shaft drive, (again, except for BMW's new K series, but even they re-worked their shaft drive for this model,) too much power is lost and they behave strangely under load. Not to mention being considerably heavier. Every pound counts on motorcycles.
I have owned all types and currently own a Harley, a Ducati, and a Suzuki, so I am not biased or married to a brand name.

Answer 2

Frankly I am irritated by some of the answers that I see here which subtract from the relevance f shaft drive. I see a lot of fanciful words on torque, power, reliability linked to the conveyer belt drive system and chain drives. Some points that I would like to put down here are the following.
1. Both belt and chain drives are exposed to the elements which means that if you are riding in an area that is typo-prone to wet and muddy conditions you protagonists of these drive mechanisms the bike has a built in propensity to fail. Riding in Africa, I have seen this first hand. The proponents of these kind of drives remind me of the supped up brain that feels the a four wheel drive is designed for city conditions. Phew! Give me a break.
2. I have certainly owned chain driven bikes and never cared for the maintenance thereof.
3. I have driven halfway up Africa and around Australia for over 40 years and the most reliable and smooth ride I have experience is from a shaft drive. Do you readers feel that this is why cars are shaft driven?
4. I read of all the negative attributes people apply to shaft drive and the control of the bike. People! This is just not true.
5. Lastly, I read about the story of performance. Those people who really want performance have to deal with one of two things, cops or a race track. In both cases you could also wind up as an estate late being dealt a hole in this ground. Anyway, shaft delivers as much power as one needs and considering that todays bikes are powerful enough. Shaft is an ample deliverer of one s requirements, even down to 400cc.
Finally, if Harley never deliver a shaft option, they will obviously not have considered the vast numbers of the "shafty" riders market out there. If Harley did have a shaft drive. Yes! I too would consider buying one.

Answer 3

Belt drive is extremely reliable. I have never broken one or a chain, but have seen it happen. Belt drives are simple, and similar to the chain drive, but quiet, clean, and almost lash free. They also were a far improvement over the chain in a day when there wasn't an "o-ring chain." Driveshafts don't go in with the style of a Harley, and don't lend themselves to motorcycles very well. They typically require the wheelbase to be extended to make room for the planetary required in the transmission. This is why you typically only see them these days on long haul road bikes like the Goldwing.

I am a Harley rider, and mostly a biker, but to who said the belt is easy to change on the side of the road, you apparently haven't had to pull the primary apart to change one before. This is one place the chain still has simplicity and superiority due to a master link. This is not what I would call a ROADSIDE task.

I have a buddy who has a Goldwing. Nice bike, but I always tell him driveshafts are for cars, LOL!!!

Answer 4

Harley built a shaft drive bike, the XA, during WW2. It was an opposed twin like a BMW. HD doesn't make a shaft drive bike now for the same reason many Jap manufacturers dropped the shaft back in the '80s. The engine configuration does not lend itself to shaft drive. An engine must be designed specifically to use a shaft. Ever ride one of the Yamaha fours from the early eighties ? When you twisted the throttle the whole bike felt like it was twisting. this was from the gear lash caused by changing the natural motion of the engine to the motion needed to turn the shaft. Opposed or flat engines like BMW or Gold Wing engines work well with shafts. Think about it they are closer to a car engine in design than a vertical or in line V-twin.

Answer 5

More reliable? how so?
True, I never broke a shaft. But I never broke a chain or a belt either.
My only shaft drive was a Yamaha V twin. Even at only 500 cc, there was noticeable torque twist.

There was some concerns (invalid) and controversy when HD went to a belt drive. Chains were reliable.

Don't rush things, when the time is right, we'll get the shaft.

Answer 6

I've read most of the answers that you have already been posted, and one of the main things to consider is "on the road" maintenance, which apparently the "technology advanced" responses haven't. If your belt should break for any given reason, a replacement or temporary can be put on at the side of the road within a relatively short time. When the drive shaft models breaks, or does something that it shouldn't, you are left on the road, till a tow truck comes along. Why are cars built with so much computers on them? to make it easier for the average garage Joe to fix? I think not. It's so the dealership have a guaranteed income for as long as you own your car. Same thing applies to the shaft driven bikes.

Answer 7

Because their belt driven system is very reliable. Also they don't want to rob the rear wheel of power like shaft drives do, plus they don't want their bikes to suffer from drive-line "snatch" which sometimes happens with shaft driven bikes.
If the belt drive were not incredibly reliable and sturdy maybe they would change to shaft. But the down side to shaft drive outweighs the benefits.
I have owned shaft, chain and belt, and it seems belt drive truly is the best option.

Answer 8

They don't want to take away from the original design.
Shaft driven is only minutely more reliable over the belt driven Harley.
I have never had a problem with Chain or belt drive motorcycles, all of them have worked just fine.

The key is to do your maintenance properly on any bike.

Answer 9

Because of history and the looks. I like my shaft driven bike, but the belt is probably lighter than the shaft. Even Yamaha uses a belt on their bigger bikes. I think chain drives are history except for the sport bikes.

Answer 10

In response to eviot44's answer, they DID have a shaft driven, horizonally opposed bike in WWII.
As far as why not, shaft drive eats up a lot of horse power, versus a chain, or a belt.