No, I am not referring to garments for larger folk here. I mean + size mountain bike tyres.
Plus (+) size tyres are in the 2.8 to 3.0 inch width range (“normal” is 2.0 to 2.4) and are a relatively new “standard” in the mtb industry. The idea is to allow tyres to be run at low pressure (10-15 psi) to give superglue-like grip and have more flex to help avoid punctures. I joined the + size crowd late last year to see what the fuss was about and have been enjoying the ridiculous grip that 3 inch tyres give. The down side is that there is a lot of rubber in a + size tyre. That mass is harder to spin up to speed and also makes it harder to change direction.
How this relates to me and my AZTR750 attempt is that I really don't need to make this race any harder than it needs to be (you could argue that using a + size 27.5 bike instead of a "normal" 29er is already enough of a handicap).
Typical 29er with 2.1 or 2.2 tyres
To this end, I have been hunting for tyre recommendations from Arizona locals on the various forums. I have learnt plenty about what people think will and will not work, tyre wise, but some of the recommended tyres aren't available Down Under.
As a result, I have used some gut instinct, some blind faith and a dash of test pilot to make the leap to purchase a couple of Maxxis 2.8 tyres. I have gone for a Rekon with EXO (sidewall protection) for the front and an Ikon, also with EXO for the rear.
My reasoning? Well, the "go to" tyre for 29 inch wheels in this race is the Maxxis Ardent, as it is tough enough to withstand the AZ desert. You can't get an Ardent in a + size, so the closest tyre I can see is the Recon. It has a waaaay more aggressive tread than I need with + size tyres but that tread will hopefully help with puncture protection. I will, unfortunately, also slow me down with a bit of extra rolling resistance.
For the rear I have, somewhat controversially, gone with an Ikon.
Controversial?
Yes, because Ikons are a bit lightweight in construction in their skinnier incarnation. I used an Ikon 2.2 on the rear of my Tour Divide bike because I didn't need that much grip, instead preferring less rolling resistance in that 4500km gravel grind. With the + size version though, that relative lack of grip isn't as pronounced because there is simply way more rubber on the trail. The real test will be to see how resilient to cuts and punctures it will be as the AZT is notoriously brutal on tyres, especially sidewalls and this is where the skinny Ikon is a bit weak. The sidewalls "feel" quite thick with Maxxis's added EXO sidewall protection even though the tyre is 120tpi (threads per inch) construction. I would have preferred both tyres to be the tougher 60tpi construction but this is where there is some compromise in + size tyres. Going too strong in the casing adds weight. Weight equals slower speed - as in forward motion and in steering feel.
Both are bad, m'kay?
You can see from the photos below how much weight I have shaved off the rotating mass just with the new 2.8 tyres, versus the 3.0s I have been running.
WTB Bridger 3.0 that I have been running on the front.
Maxxis Rekon 2.8 that will replace the Bridger - 297grams saved (10.5 oz)!
Maxxis Chronicle 3.0 (60tpi) that I have been running on the rear.
Maxxis Ikon 2.8 that will adorn the rear - 227g (8 oz) saving!!
Only time will tell if I have chosen wisely. + size tyres aren't cheap, so I will be sticking by my choice unless I can prove them to be unworthy over the next 4 weeks prior to the race. This means getting the Beast loaded up and hammering it across some rocky, unforgiving trails. Unfortunately (or fortunately) we don't have the cacti problem so I can't simulate that particular issue in trying to expose any weakness. While a 524g (1.15 lb) saving is significant, it is worthless if the tyres let me down on day one in the Canelos.
Not rocky, nor unforgiving - but it was on the way to find rocky and unforgiving!
Fingers crossed I have chosen wisely.....................or that I ride lucky...........!
I will be happy to take either.
Cheers
How this relates to me and my AZTR750 attempt is that I really don't need to make this race any harder than it needs to be (you could argue that using a + size 27.5 bike instead of a "normal" 29er is already enough of a handicap).
Typical 29er with 2.1 or 2.2 tyres
To this end, I have been hunting for tyre recommendations from Arizona locals on the various forums. I have learnt plenty about what people think will and will not work, tyre wise, but some of the recommended tyres aren't available Down Under.
As a result, I have used some gut instinct, some blind faith and a dash of test pilot to make the leap to purchase a couple of Maxxis 2.8 tyres. I have gone for a Rekon with EXO (sidewall protection) for the front and an Ikon, also with EXO for the rear.
My reasoning? Well, the "go to" tyre for 29 inch wheels in this race is the Maxxis Ardent, as it is tough enough to withstand the AZ desert. You can't get an Ardent in a + size, so the closest tyre I can see is the Recon. It has a waaaay more aggressive tread than I need with + size tyres but that tread will hopefully help with puncture protection. I will, unfortunately, also slow me down with a bit of extra rolling resistance.
For the rear I have, somewhat controversially, gone with an Ikon.
Controversial?
Yes, because Ikons are a bit lightweight in construction in their skinnier incarnation. I used an Ikon 2.2 on the rear of my Tour Divide bike because I didn't need that much grip, instead preferring less rolling resistance in that 4500km gravel grind. With the + size version though, that relative lack of grip isn't as pronounced because there is simply way more rubber on the trail. The real test will be to see how resilient to cuts and punctures it will be as the AZT is notoriously brutal on tyres, especially sidewalls and this is where the skinny Ikon is a bit weak. The sidewalls "feel" quite thick with Maxxis's added EXO sidewall protection even though the tyre is 120tpi (threads per inch) construction. I would have preferred both tyres to be the tougher 60tpi construction but this is where there is some compromise in + size tyres. Going too strong in the casing adds weight. Weight equals slower speed - as in forward motion and in steering feel.
Both are bad, m'kay?
You can see from the photos below how much weight I have shaved off the rotating mass just with the new 2.8 tyres, versus the 3.0s I have been running.
WTB Bridger 3.0 that I have been running on the front.
Maxxis Rekon 2.8 that will replace the Bridger - 297grams saved (10.5 oz)!
Maxxis Chronicle 3.0 (60tpi) that I have been running on the rear.
Maxxis Ikon 2.8 that will adorn the rear - 227g (8 oz) saving!!
Only time will tell if I have chosen wisely. + size tyres aren't cheap, so I will be sticking by my choice unless I can prove them to be unworthy over the next 4 weeks prior to the race. This means getting the Beast loaded up and hammering it across some rocky, unforgiving trails. Unfortunately (or fortunately) we don't have the cacti problem so I can't simulate that particular issue in trying to expose any weakness. While a 524g (1.15 lb) saving is significant, it is worthless if the tyres let me down on day one in the Canelos.
Not rocky, nor unforgiving - but it was on the way to find rocky and unforgiving!
Fingers crossed I have chosen wisely.....................or that I ride lucky...........!
I will be happy to take either.
Cheers