[SpartyBiker]

I took a few minutes to look at the specs for dirt bike tires, which happen to be close to that of the 29er.

For example, Dunlop makes a dirt bike tire (front) that has a 28.52" diameter, and 3.72" width, and a pricetag that is around $50/each.

Knowing that, what are the technical aspects that would stop me from mounting these tires?

I'm already thinking that a custom fork and frame would be needed to accept the tires width, but that's about all I can think of.

What do you guys think?

 

[ebotto]

The bead is not going to fit on an MTB rim.

 

[SpartyBiker]

If the dirt bike tire's bead doesn't fit the MTB-rim, then I would think to make the rim fit the bike--right?

I'm not an expert but I think that it would be a safe bet to say that a wheel hub from any manufacturer, and a set of spokes that are for a 29er wheel, could make it work?

What's stopping someone from combining the tire/rim off the dirt bike and the spokes/wheel hub off the mountain bike?

 

[ebotto]

What's stopping someone from combining the tire/rim off the dirt bike and the spokes/wheel hub off the mountain bike?

Size, weight, necessity. Dirt bike rims are pretty beefy. I don't think MTB spokes would support a dirt bike rim. Go into a local motorcycle shop and pick up a dirt bike tire. There would be no benefit to make it work.

 

[shiggy]

If the dirt bike tire's bead doesn't fit the MTB-rim, then I would think to make the rim fit the bike--right?

I'm not an expert but I think that it would be a safe bet to say that a wheel hub from any manufacturer, and a set of spokes that are for a 29er wheel, could make it work?

What's stopping someone from combining the tire/rim off the dirt bike and the spokes/wheel hub off the mountain bike?

First, it has been done. Doug Bradbury (the Manitou founder) built a DH bike in the '90s with 3.something-inch wide motocross tires and rims.

Why would it not be a good idea?

A pair of moto tires and rims alone could weigh more than a whole mtb.

The tires are designed to support several hundred pounds of motorcycle plus the rider weight. They are so stiff you could run them on a mtb without air pressure in them. Bad for traction and control.

Moto spokes/nipples are MUCH larger diameter than the mtb counterparts. Not a simple thing to lace moto rims to mtb hubs.

Also, the actual diameter of moto rims are smaller than 26" mtb rims.

 

[SpartyBiker]

Great response that answers my curiosity to the question. I know I wouldn't really try to pair dirt bike tires with a mountain bike, but the thought of it seemed do-able.