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Bias and radial tires at the same time?


Junior Member

Ever since I began riding I've heard as gospel that we should never mix bias and radial tires.

But yesterday my copy of Enthusiast arrived featuring the Crossbones, with the specifications showing a bias front tire and a radial rear. So is the gospel wrong, or have the tires (or bikes) themselves been changed, or is MOCO experiencing heresy in the design department?

And so can I convert my FXD to radials, one at a time?

Here's a copy from the HD site on the Crossbones. Is this the only bike with this combo or do some of the others do this?


Front Black, Laced Steel

Rear Black, Laced Steel

Tire Size

Front D402F MT90B16 72H

Rear D407 200/55R17 78V


Regardless of what anybody says, I wouldn't mix the two on the same bike because of different handling characteristics between them. Just not worth it when you are on two wheels IMO
I agree with Glider !! Why would you want to mix the 2 anyway. Each tire has its own traction characteristics. I am no expert but I know what happens in a sharp curve while driving a car with 2 bias tire on the back and 2 tire radials up front.
She went into a 360 and that was that.
The tires on many of the Soft tail series are radial rear and bias ply front. My guess is that it is simply a styling decision, Fat rear tires are "in" on chopper customs, likely bias tires aren't made at 200MM and wider for motorcycle rims and I know there are no radials available for the skinny 21 inch rims. I suppose if you really hot rodded your Harley you'd need that fat tire for traction or drag racing, but they are pretty expensive to replace which you'd be doing pretty often if you're into smokey burnouts.
Here's a tech answer from the feb issue of "Cruiser" mag on swapping radials for bias.

"Bias belts and radisal tires are two completely different animals. They react to the road in contrasting ways and impart dissimilar cornering stresses to the motorcycle--- a bike designed to work with one type of tire generally doesn't work nearly as well with the other. Since your bike wasn't intended to use radials, installing themcould affect handleing, stability, and safety for the worse (the operative word here being "could"). You may also install them and think they are the best thing since sliced bread. But since niether your manufacturer nor tire maker approves the different tire for you bike, I'd say the smart bet would be to staywith what the bike is designed for."

Hardly definitive but thought an FYI from a tech not directly involved with the bike maker or tire maker might be helpful.