Custom drive shaft for motorcycle..
Had a customer ask me over the phone if I could make a drive shaft for a motorcycle. Didnt think about it that much and said that I probably could but I wanted to see the shaft first and see what it looked like.
Now I did a little quick searching and I am surprised to find that no one makes drive shafts for motorcycles. At least there isnt anything about it on the internet that I could find. Does anyone know if there are any experianced drive shaft shops around who do motorcycles?
Did he say what brand of motorcycle?
He could just buy one, or buy one and adapt it for the special purpose. A commonly-known
sort of drive-shafty motorbike:
There's another shaftie behind the first one visible.
Moto guzzi, honda, kawasaki, all make shaft drive bikes of one flavor or another.
If one wanted to obtain a starting core to work from, a /5 or /6 shaft would probably
be available via ebay, or via this site:
If price were no object, capitol cycle, or bob's bmw would be the first choice to
find NOS hardware. But used ones are often modified for various conversion
? for jim r, i have r100r w/60k mi. the shaft on mine has 2 u-joints that get eaten up every 25-30k@ $550 per assy. have you ever run across after market u-joint kits for beems? surf
Charles, drive shafts are an infrequent need and most of them are available from a friendly local dealer. Big-block Guzzis have several different shaft lengths to accomodate changes in swing arm length. Small-block Guzzis also have several lengths as well as several different splines.
Unless someone is doing a custom swing arm length that needs a custom shaft, or they've got a bike that just isn't supported any more, I don't think there'd be any market for aftermarket drive shafts.
MV Agusta & Yamaha also made shaft drives. Plus a few rare vintage MC's (Militor, Curtiss V8, etc)
Lots of cruisers have shaft drive too. All of the Big Four Japanese brands have had shaft-drive bikes. I think the MV would fall into the "rare vintage" class.
Lots of potential donor bikes, lots of research to do to see if something is workable.
If the guy needs a driveshaft made, then he must already have a bevel-box at the engine and a gear-driven hub for the wheel. First thing I'd do is find out what fitments you have to cater for.
Motorcycle driveshafts are tiny in cross-section compared to car propshafts and usually solid. If you are going to make one remember it will need to have a sliding-spline to allow for length changes as the suspension swings. I'd take Jim's advice and find a pre-existing system to modify.
I think about every motorcycle maker has built a shaft drive bike. Other than the up and down pogo stick effect on and off throttle, they are a great idea. Once you get used to that, they are fine, but it can sneak up and bite you if you are not used to it. You can be heeled way over and drop the throttle in a turn, the suspension drops, you drag something and lift the rear wheel. That's why I hated my Suzuki GS850L, it was already too low (being the cheezy cruiser model), and this made it downright dangerous on washboard turns. Can also get you when you get on the throttle exiting a hard turn... heeled way over, front wheel light, power causes wheel spin, shaft unloads and suspension drops, leaving the bike in mid-air. Ask me how I know this. Shaft drive Honda 650 Nighthawk.
My fave shaftie was a 1983 Yamaha 750 Seca. Zero maintenance sport/touring bike that was just blistering fast, excellent brakes and handling, tons of ground clearance, and extremely comfortable. I'd actually love to find another one for a daily rider.
Peter, the sliding spline is usually at the tranny end of the yoke, not in the driveshaft itself.
Also OT, but many years ago as a kid, I went to a bike shop downtown. Hanging on the wall was a shaft drive bicycle, of obviously very old vintage. One of the lower rear tubes was hollow. That was the shaft support tube. The shaft had a crown gear on each end. The front "sprocket" was a crown gear, and there was a mating crown gear on the rear hub.
i have seen some made for yama 1200 vmax's ,they have a huge following around the globe. google it
Don't mess with Mr. Max.
They say there are two kinds of riders. Those that have not ridden a Vmax,
and those that have.
i have one. 11 flat at 124mph on the drag strip no motor work done. awesome ride
On the older bmws, the sliding part is at the bevel drive in the back. Universal is fixed
at the end of the gearbox, and as the suspension moves up or down the slack
happens between a sort of male/female gear setup at the back. The total amount
of linear motion is probably about a half inch or so.
ON the newer ones (paralever) there are two joints, one front and one back.
The fun thing about the older bmws is that when you let out the clutch with the
front brake on , the entire bike rises up from the ground: the back wheel from
the shaft reaction, and the front wheel because of the earls fork geometry.
I was able to rebuild the U-joint on my R60/2 drive shaft. All it takes is four
needle bearings and precision spacers to center everything. Was not so easy but
when I finished it the shaft runout was better than stock. I also did a full rebuild
on the entire bike along with a stainless fastener conversion. Made custom bags
with sewn up leather. BTW you ever hear of a gentleman named Ed Korn?
Well thank you for the replies so far, as it is this person needs a longer drive shaft than is factory available. Some kind of custom motorcycle that I havent seen yet and I dont remember what the brand name was.
My question was more along the lines of whether or not it is common for people to have custom ones made and who does this work. I was really surprised to find out that an internet search didnt find any reference of any kind. Makes me wonder if there is some reason for this?
Some of you mentioned modifying, what do you mean by that? What kind of modifications are normal? I havent seen this drive shaft yet so I dont know how much work it is to make a new one but is there some reason why I shouldn't?
The drive shaft universal joint is where I would start. If your customer has one
Originally Posted by CBlair
that he wants copied it may be that the unit is made to be rebuilt. I was in a situation
where my shaft was not made to be rebulit but I did not want a used shaft so I took
my original shaft with universal joint and replaced the four needle bearings. Not as easy
as it sounds. But I know that you can buy universal joints brand new. In my case the shaft
and 1/2 the universal joint was one piece.
My guess is that the person probably wants a longer shaft for some sort of custom swing arm on his motorcycle. The only motorcycle drive shaft I've ever handled was on my former 1500 Goldwing motorcycle. I used to remove it and lubricate it with Honda Moly grease whenever I changed tires. It was quite well made. It would be quite a job to make one, considering the metal involved, splines on both ends and the matter of obtaining the final hardness.
Last edited by Newman109; 10-11-2009 at 03:25 PM.
That were some of my thoughts afterward...I was looking for some reference as to what kind of material and how critical heat treatment would be but cant seem to come up with that. I really dont want to guess at it so I was hoping for something better than just opinion.
I dont have to do the work but if I send the guy away I really want to have some concrete information about why and what he needs to be aware of if he wants to continue the way he is.
Really surprised that I couldnt find more information about this.
I don't think this sort of thing is done very often. I do know this from experience, having seen and heard of these shafts breaking - the material and hardness on such a part is absoutely critical. Even factory ones have been known to break. The usual problem on any of the many models of Honda bikes with shaft drives is failure of the owner to do any periiodic lubrication on the splines. They simply wear out and the shaft breaks from the shock of running loose.
Originally Posted by CBlair
I can't thnk of where you might find any informaton on this sort of a project either.
From site listed above:
misc. airhead parts
swingarm/driveshaft(lwb)very good splines and U-joint$125