Recommend me a 2.1-2.4 29er xc tire!

[TheseGoTo11]

Can't go wrong with Ikons. I've had good experience with the Schwalbe options mentioned above, too, but they seem to wear faster.

[tommyrod74]

Race kings have more than enough traction for my local terrain, but eventually I carry too much speed through rocks and rip a hole in them. They roll unbelievably quickly. Nothing else comes close. Excellent weight as well.

Maxxis Ikon feels like pedaling through tar, and the traction is no better than the Race King. They do seem to be durable, at least. Aspen is a better tire for most applications, at least as much a grip as the icon but rolls faster. Still nothing like the race King.

Currently, I’m on the new specialized renegade 2.35, in the T5 compound. I just finished an extremely rocky - as in loose shale and slate, so very sharp rocks – With zero problems. Good traction for a tire so fast. It’s not a race King but then again nothing else is, and this seems to be significantly more durable. I have the control casing version, I would not use the S works version unless it was a smooth course, for racing only. I was honestly amazed at the fact that I finished the race at high speed yesterday with zero problems related to tires. I hit some rocky sections at super high speeds and it took it like a champ. They do need more pressure than you would expect; I’m used to running 20 or 21 psi and these need about 25 or 26 because th with zero problems. Good traction for a tire that rolls so fast. It’s not a race king, but then again nothing else is, and this seems to be significantly more durable. I have the control casing version, I would not use the S works version unless it was a smooth course, for racing only. I was honestly amazed at the fact that I finished the race at high speed yesterday with zero problems related to tires. I hit some rocky sections at super high speeds and it took it like a champ.

They do need more pressure than you would expect; I’m used to running 20 or 21 psi and these need about 25 or 26 because the Sidewalls are so supple. They still ride well at these pressures. I ended up with 26 rear, 23 front and was very happy at 160 pounds body weight.

A side benefit of these new tires is they are only $60 a pop. That’s a heck of a lot cheaper than anything the competitors had at this level. They aired up immediately with the floor pump.

[EB]

I absolutely love the new Specialized Ground Control. I’m using the GRID T7 as a rear tire on a trail bike, but it comes in lighter/racier casings, including a 595 gram/2.1” S-Works version if that’s your thing.

PB has a good review here: https://m.pinkbike.com/news/review-s...-t7-tires.html

Best part is that they come in a very nice tanwall as well as black, and they’re $30 cheaper than Maxxis!

[tommyrod74]

Originally Posted by Eli Bingham

I absolutely love the new Specialized Ground Control. I’m using the GRID T7 as a rear tire on a trail bike, but it comes in lighter/racier casings, including a 595 gram/2.1” S-Works version if that’s your thing.

PB has a good review here: https://m.pinkbike.com/news/review-s...-t7-tires.html

Best part is that they come in a very nice tanwall as well as black, and they’re $30 cheaper than Maxxis!

I was borderline on trying the grid casing on the rear at least as I’ve had two flats that took me out of contention and recent races. One was on an S works renegade - the previous version - and one on the race king. Again, I was very happy with how well the control casing held up yesterday. I think I’ll try a ground control upfront in a 2.35 in the control casing over the winter.

[benb]

Related question for this kind of riding/racing.

What kind of gearing do you run with a modern XC bike when there's an assumption some fast rolling is going to be required or a sprint?

I am riding an ancient bike that's still 3X but I'm starting to get curious about replacing it.

The gearing on these modern bikes seems insanely low. My bike has fairly standard gearing for XC for it's time and it's geared to be able to pedal 29mph at 90rpm in the top gear, so it has room for a 30mph+ sprint. (44x11 with a 26" wheel).

The races I did back in the day I absolutely made use of that 44 chain ring and on smooth sections those upper gears definitely came into play.

The flipside is I have a 22x32 on that bike on the low end and about half the cassette on that 22 ring is almost useless, the gears are so low you can only kind of use them on something that's really steep but completely void of any technical challenge. If you have to stop and the trail is technical you can't really get going again those gears are so low. The bike just doesn't move forward enough to balance as you get going again, especially if you have to clip in.

I look at some modern 1x bikes and they are geared to go about 23mph at 90rpm in the top gear and they have quite a few gears *lower* than my 22x32.

Is this just an artifact of stuff like Enduro and the whole free ride culture where MTB guys stop a lot on the trail and "session" a rock over and over? Or do XC bikes get changed out to taller gearing?

I guess you get > 30mph sprinting at 120rpm with a 32x10 on a 29" wheel so maybe it's OK for a sprint and it looks like the real race oriented hardtails can take a 36 ring.

[EB]

Originally Posted by benb

Related question for this kind of riding/racing.

What kind of gearing do you run with a modern XC bike when there's an assumption some fast rolling is going to be required or a sprint?

I am riding an ancient bike that's still 3X but I'm starting to get curious about replacing it.

The gearing on these modern bikes seems insanely low. My bike has fairly standard gearing for XC for it's time and it's geared to be able to pedal 29mph at 90rpm in the top gear, so it has room for a 30mph+ sprint. (44x11 with a 26" wheel).

The races I did back in the day I absolutely made use of that 44 chain ring and on smooth sections those upper gears definitely came into play.

The flipside is I have a 22x32 on that bike on the low end and about half the cassette on that 22 ring is almost useless, the gears are so low you can only kind of use them on something that's really steep but completely void of any technical challenge. If you have to stop and the trail is technical you can't really get going again those gears are so low. The bike just doesn't move forward enough to balance as you get going again, especially if you have to clip in.

I look at some modern 1x bikes and they are geared to go about 23mph at 90rpm in the top gear and they have quite a few gears *lower* than my 22x32.

Is this just an artifact of stuff like Enduro and the whole free ride culture where MTB guys stop a lot on the trail and "session" a rock over and over? Or do XC bikes get changed out to taller gearing?

I guess you get > 30mph sprinting at 120rpm with a 32x10 on a 29" wheel so maybe it's OK for a sprint and it looks like the real race oriented hardtails can take a 36 ring.

Short answer is that the people at the pointy end run a 36 tooth ring. 36x10 on a 2.35” tire at 100 rpm is 31mph (approx)

[benb]

OK makes total sense.

Some of the bikes seem to be coming with 30 rings even, but those must not be used on the pointy end.

[AJosiahK]

if the terrain youre riding isnt too gnarly / sharp I have really liked Schwalbes options, RockRazor in rear, RocketRon or NobbyNic up front. They are supple, grip, set up TL easy etc. They dont last as long as a Maxxis or Spesh, and are more prone to cuts but outside of that great XC tires.

That being said, I ride mostly Maxxis and Vittoria treads for more gnarly stuff.

cheers

[fmradio516]

Originally Posted by AJosiahK

if the terrain youre riding isnt too gnarly / sharp I have really liked Schwalbes options, RockRazor in rear, RocketRon or NobbyNic up front. They are supple, grip, set up TL easy etc. They dont last as long as a Maxxis or Spesh, and are more prone to cuts but outside of that great XC tires.

That being said, I ride mostly Maxxis and Vittoria treads for more gnarly stuff.

cheers

Just curious what Vittoria are you running? Ive been running DHR+DHF but wondering if theres anything that rolls a little better.

[EB]

Originally Posted by benb

OK makes total sense.

Some of the bikes seem to be coming with 30 rings even, but those must not be used on the pointy end.

30 tooth is for winching your 33 lb sled up the 17% grade to the top of the hill. I’m a fan.

[Overshot]

Ive had good success with 2.25” Thunder Burts on a drop bar MTB. On a recent route I did this included 150+ miles of paved roads and they did surprisingly well. Not road bike fast by any means but much better than expected for a MTB tire. After 1K miles on these I am very pleased how relatively little wear they have. They are fast rolling off road, but are also a little slippery in mud / wet.

[tommyrod74]

Originally Posted by Eli Bingham

Short answer is that the people at the pointy end run a 36 tooth ring. 36x10 on a 2.35” tire at 100 rpm is 31mph (approx)

Longer answer is yes, but it depends on the course. I run a 34 or 36 depending. Last weekends race was 4.25 hours, 6400 feet of climbing, much of it steep. The 34 x 52 was definitely used, the 34 x 10 only once on a long downhill gravel section. No such thing as a sprint on a race that long, and I was at the pointy end. 34 x 10 is still plenty to sprint if it comes down to that.

[xcandrew]

Originally Posted by benb

The gearing on these modern bikes seems insanely low. My bike has fairly standard gearing for XC for it's time and it's geared to be able to pedal 29mph at 90rpm in the top gear, so it has room for a 30mph+ sprint. (44x11 with a 26" wheel).

Here's Strava for Ondřej Cink, one of the top cross country riders in the world. He was third place at the last World Cup XCO race. His max speed during the race was only 27.5 mph.

https://www.strava.com/activities/5988070898

At the World Championships, he was in third place until he had a mechanical (XTR shifter failed). Max speed was only 28.9mph.

https://www.strava.com/activities/5867176674

[tommyrod74]

Originally Posted by xcandrew

Here's Strava for Ondřej Cink, one of the top cross country riders in the world. He was third place at the last World Cup XCO race. His max speed during the race was only 27.5 mph.

https://www.strava.com/activities/5988070898

At the World Championships, he was in third place until he had a mechanical (XTR shifter failed). Max speed was only 28.9mph.

https://www.strava.com/activities/5867176674

Moreover, I’d be willing to bet good money that both of those top speeds occurred when he was coasting downhill, on a section were pedaling would’ve been almost impossible, with no advantage to doing so. Modern XC bikes have plenty of top end gearing.

[hellvetica]

Ikon for fast-rolling (rear), Ardent for traction (front)