INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Jobs

Wire spokes on sport bikes

Wire spokes on sport bikes

(OP)
Wire wheels are associated with tubs and usually put on dirt bikes, dual sports, supermotos, and certain cruisers.  And they usually have inner tubes,and are maintenance intensive, but there are manufacturers out there that have made advancements on the design to run carefree and tubeless.  (http://www.alpinaraggi.it)

Cast wheels are on everything else.

My question is why?  And are there benefits or cons with either type of wheel?

Is it that the wheel would experience deflection on higher performance bikes? (i.e. axle twisting relative to the rim.)  

I know the downfall of wire rims on cars are that they deflect excessively under lateral loads.  But I don't think a motorcycle rim would ever see that kind of lateral force.  

Is it just a style/trend/manufacturing ease thing?  Are there any reasons wire spoked rims wouldn't work on sport bikes?

RE: Wire spokes on sport bikes

Wire wheels worked just fine for decades.
Alloy, once the bugs were worked out, was cheaper.
 

Mike Halloran
Pembroke Pines, FL, USA

RE: Wire spokes on sport bikes

Only advantage I can think of for wire wheels are that they are more damage tolerant in impact situations. This is a good feature for dirt bikes and dualsport bikes. Also, wire wheels are a little bit lighter. Only other reason you see wire wheels is strictly for style.

RE: Wire spokes on sport bikes

Motorcycle wheels see lateral force when going over bumps. Also, with modern wide tires, when leaned over, the contact patch is significantly away from the centerline of the wheel, which means there is a lateral component to the force on the wheel.

Also, it may be non-technical, but wire wheels look old skool, and just don't fit in with modern styling on the rest of the bike. I've seen pictures of otherwise modern-looking small bikes in Asia with wire wheels, and they just look wrong, it doesn't fit with the way the rest of the bike looks.

RE: Wire spokes on sport bikes

I would guess that the widespread adoption of radial tires to motorcycles affects the spoke vs cast wheel decision.

RE: Wire spokes on sport bikes

Wire spoked wheels are labor/cost intensive to manufacture to equivalent dimensional tolerances of cast wheels.  Yet most bicycles still use spoked wheels, so perhaps sport bikes passed some power density point on the strength/weight/cost triangle that sent them to cast.  This may be supported by the observation that modular wheels (i.e. comstar) saw employment during the transition.  

Lateral forces are a concern with high performance MC wheels- 5-10 years ago some designers recognized they had developed chassis that were TOO stiff, as MCs need some lateral deflection for suspension when leaned way over in turns. So now they design controlled lateral flexibility back into high performance frames.  The question makes me wonder whether they considered wheel flex- maybe not as racing wheels are sometimes developed out of house, so that wasn't a lever they could easily adjust.

Might be a good student design project.

RE: Wire spokes on sport bikes


    Could a solid tubeless rim be mounted on a float type hub with shock absorption ? the spokes could be capable of compression and extension ? Could this be done in a cost effective modular,repairable manner ? Lateral and radial compliance could be tuned .
                 Regards,Ed     

RE: Wire spokes on sport bikes

(OP)
Ed,

I would think that as soon as the wheel hit a bump and threw the wheel off center, all hell would break loose.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close