[Richard230]

Bike Bandit (a CA-based internet motorcycle accessory store) has published an mildly interesting article comparing radial motorcycle tires with bias-ply tires. One of the things that I found fascinating is that they say never to use radial tires on spoked wheel rims using inner tubes. I found that kind of funny as my 1997 BMW Funduro came from the factory with spoked wheel rims, inner tubes, a bias-ply tire on the front wheel and a radial tire on the rear wheel. Like I always say, BMW does things their way and not anyone else's way. 

http://www.bikebandit.com/blog/post/bias-ply-vs-radial-which-one-is-best-for-you

[REpozer]

I thought radial tires are tubeless with a need for dissipate heat. So no tubes.
 Spoke wheels are generally tube tires.

[Richard230]

I thought radial tires are tubeless with a need for dissipate heat. So no tubes.
 Spoke wheels are generally tube tires.

It would appear that some German engineers know more than you do - or the tire companies that design and manufacture the tires.    I might add that the rear radial tire on my BMW Funduro got really hot if you didn't keep the tire pressure up and the hotter it got the faster it wore. I agree with Bike Bandit's recommendation to use a bias-ply tire when you have a spoked wheel needing a tube in the tire.

[Ice]

 Meh. I will ignore the authors advice on the use of tubes with radials and instead follow H-D's list of radials approved for fitment (and with tubes no less !) to my machine.

[crock]

I don't know where Bike Bandit got the information about not using tubes with radial tires. The Conti Attack radial sold here for replacement of bias ply tires can be run with tubes and Conti specifically says so. Also, there are a few OEM spoked wheel radial tire with tubes bikes out there, and not just on BMW's. I think the no radials with tubes advice is bogus. The earlier rule of thumb was to rate the tire one speed classification lower when using tubes. Hardly a problem with a Bullet!