Why Run Different Tires Front and Back?
 

Hia ll -- I'm a XC trail-riding newbie shopping tires. I ride mostly dry singletrack (includes roots, rock gardens, loose corners, small jumps, etc., but primarily dry hardpack), and also use my bike to commute to work.

I was lookin at reviews of the Maxxis Larsen TT tires, which seem appropriate for my dual trail-commuting needs. However, several of the reviewers say they put a Larsen on the back and something else (usually a bit wider, more knobby) on the front. Some say outright, with respect to trail use, "Do not use a Larsen on the front."

My newbie question is: what is it about the work the front tire does relative to the back tire that causes some to use different tires front and back?

Thanks much for any replies.

On the back I run a slicker smaller tire for increase speed while on the front I run something bigger, usually run it a little softer and with larger knobs for increase steering.

This, for me, is just how I like it. When I lean the bike it hooks up really well. If I am riding xc I use rounder (instead of square profile) tires with smaller knobs. Usually matching as I am not going at speeds where I notice the smallest imperfection in my tires.

The front and rear of the bike do very different things. The rear tire needs to have grip for traction as you climb while the front needs traction for steering. The traction for the rear needs to be more in the center of the tire rather than on the edge while you want good edge control for a front tire.

On my fully rigid SS, I run a 26x2.5 up front, and a 26x2.2 in the back. The treads are different as stated above for getting the most out of that wheel. Another reason I run a bigger tire up front is to help soak up the bumps. When I first built up the bike I ran a 2.2 upfront. Since putting a 2.5 up front, I've noticed some difference in the steering characteristics. But I'm racking that up to a tire with better side grip.

A good example of what cyccomute is saying, would be the Panaracer Smoke and Dart tires. The rear (Smoke) has a "paddle" like design for laying down grip for acceleration/climbing. While the front (Dart) has an arrow like pattern for more lateral grip.
http://www.panaracer.com/eng/products/mtb/xc.html

I was going to use that as an example but decided not to! When the Smoke came out...long ago...I ran them on both ends. Big mistake! The Smoke would hold on to the ground in a turn or on rocks to the very end and then suddenly break loose, usually leaving me on the ground. It was a very scary front tire. Put a Dart on and the bike goes where you point it. They are still a great tire and they wear like iron.

Thanks
 

Thanks much for the responses! Definitely makes sense now. I guess in light of the advantages I'm surprised more tire sets don't do the Dart-Smoke type-combo, although I suppose a good all-around tire will do the job just fine front and back for the majority of typical riders (especially neophytes like me). I have IRC Mythos XC tires now, and am looking forward to trying a different set for comparison and contrast if nothing else. Maybe I'll try the wider up front, narrower in back combination as well.

Thanks again for taking the time to respond.

Have you ever tried a Dart in both front and back??

we have some sandy trails here so i run a 1.95 rear and a 2.3 front on my HT...i've found that the fatter front keeps from sinking in the sand on the descents and gives better control...quite a slog on the climbs, though

No. I don't think the Dart would have grip for a rear tire even if you put it on backwards. Plus the Smoke is really an excellent rear tire especially for the hardpack/loose gravel of the Colorado.

Be aware that tires can be rather specific to areas too. What works in Colorado doesn't in New England, for example. It's usually best to ask around at your local shops or clubs to see what works for people in your area.

+10

I was looking into those pana's for my fsr. Any one know anything about the wtb veloci-raptors? Same problems as with the pana's??

Maybe start a new thread, likely to get more responses as this is a little older and most won't check in on it :)