Daspydyr 

I've been shopping for some new tires lately and have seen that several manufacturers make 2.0 XC tires that they boast have several World Cup Wins! I know that the tires are light, but they seem squirrelly to me. I am running a Geax Saguaro 2.0 on the back right now. It is great on hard pack, but if I get into marbles or sandy trails the back end seems to move around and loose grip. I am still running a 2.1 Karma on the front and am really impressed with it. I can't seem to wear it out and I am confident that it holds in corners, no matter what the trail condition.

I always thought that I could run a thinner rear tire and keep the weight and rolling resistance down. Now I'm wondering if its worth 100 grams? What do you guys think?

Hocam

Couple-o-things:

1-Rotational weight has way less influence than people want to claim. In fact so does non-rotational weight. It's really just manufacturer marketing trying to sell you more expensive, lighter products with a fatter profit margin.
2-Fitness is going to have a way bigger influence on speed than rolling resistance.
3-Having to brake going around corners because your tires don't bite is probably going to slow you down more than increased rolling resistance.
4-Buy a second wheelset and have two tire options for different conditions

3speed

Maybe it's just the particular rear you're running? People tend to be able to get good performance out of a less aggressive rear tire, and you're only running a 2.1" in the front, so I wouldn't think that .1" in the rear would make much difference. I run a 2.25" front and a 2.0" with less knob in rear and don't have issues with the rear sliding out when pushing really hard into some corners. In fact, my front will often go with or just before my rear(which isn't good). I know a lot of people run bigger difference in tire size than you're running and it works out great. I think maybe it's just that Geax Saguaro 2.0. I also just quick checked out a review site and a lot of the reviews say that tire tends to wash in corners and loose gravely type stuff.

Daspydyr 

Thanks guys, hey 3, where do you find your reviews?

dminor 

I personally use everybiketireinthewholeworldprofessionallytestedandreviewed.com

3speed

I just use the common simple MTBR.com. Basically what I've found with it is that if a product really is good, it'll get consistent great reviews on MTBR. Something like your tire, for example, gets pretty mixed reviews, with half of them being the exact problem you're talking about. It makes sense when you think about it. Of course there are always going to be some people that will be happy with a tire, so most all will get some good reviews. But in my experience with products I've used personally, if it's got pretty mixed reviews, you're probably gonna find the same issues that people state. I've used a couple products reviewed on there that have consistently high reviews and they've been great. I've used some that had mixed reviews and been willing to accept the weaknesses, sometimes not, but usually mtbr will point out those weaknesses. I like the site enough that I pretty much check everything on there before making a purchase.

Dilberto

World Cup riders also ride ultra-smooth, groomed courses with nary a rock, sand or thorn present. In real world riding - you need at least a 2.10" tire to keep your skin and teeth intact.

ESW116

I clicked on that

Daspydyr 

Yeah, I was afraid I would get dougpunked on that!

dminor 

^^ At least it wasn't the rickroll from hell. I got properly flogged for that one.

commo_soulja

Wait a sec... a 2.0 tire is skinny?

My first mtb outta high school was shod with 1.85 tires and between that size and 1.9 was the norm. 2.0 was considered fat.

3speed

^ I actually just checked out some 1.9s on an old bike tonight. Looks like it's actually a great tread, at least worth trying, but I don't know how I feel about the size. The overall tire volume of a 1.9 just seems too small to get the kind of squish to smooth out the bumps and choppiness in the trail. Hmm...

dminor 

Fixed.

redtires

Your not alone my friend...


But back to the post....I personally think that tread and the quality and ride characteristics of the casing make a huge difference in how a tire will perform. One of my fav's from long ago was the Conti cross-country 1.5's. I rode the **** out of those all over the front range. I tend not to be a total bomber though, so if that's your style a tire like that probably wouldn't do too well.

M_S

lol.

Daspydyr 

^^^Point well made, those rocks are smooth, no goatheads and the place looked groomed! I hear there was a sponge pit at the bottom of that run!

ColinL

Pros are pros. Just because they can do awesome things on 1.8 - 2.0" tires doesn't mean that we can do it too.

It's far easier to ride over rocks with large volume tires, no one is ever going to dispute that.

Leebo

2.3 to 2.5's rock the rocks.

24/7biker

with a narrower tire you don't have as much room to play with tire pressure. this is probably why you are having trouble with your rear tire. try a bigger tire, drop the air pressure down and you'll probably get a lot better traction in the loose stuff. there are lots of tires out there now that are in the 2.3" range but are also really light.

Lord Chaos

I've used a lot of tires over the years... the hot setup in the 1980s was a Ritchey Quad in back, and a Specialized Ground Control in front. This worked very well. Of course, none of the tires I rode then is still available, so I've gone through various other combinations. My current favorite is the WTB Weirwolf, a 2.3 in front and a 2.5 low knob in back. The Weirwolf grips well, and hangs on in sandy/pebbly/loose-dirt curves. They even roll decently on the pavement, on the way to the mountains.

Dilberto

How scared do you want to be? Try doing 30mph+ on a downhill fireroad with skinnies(1.9"-2.0") and your chamois will be soiled with this morning's coffee...