Hit the nail on the head with q factor
A little more detail in this article including
āSRAMās engineers were able to add a 13th sprocket, while using the same 12-speed Flattop chain as found on the brandās other AXS groupsets.ā
āCompatible with all existing 12-speed AXS componentsā
1 Like
3 Likes
1 Like
32mm ID wheels? 
5 Likes
There is a lot to like with the new XPLR 13spā¦ The fact they avoided adding another chain type to their lineup is really nice, and I like the cassette spacing a lot.
But man that price is tough to swallowā¦ Just built a cart with only the Red E1 Levers, XPLR 13 Cassette, and XPLR 13 Derailleurā¦ No crankset, chain, or battery. Still $2900!
Iām not one to complain about inflation or prices, but truly six or seven years ago you got a full Sram Red equipped carbon bike for thatā¦
6 Likes
I never thought that it made sense to use 25mm ID wheels for gravel.
So many companies have been saying that 25mm is the best for 28mm road tires, so why use the same width for gravel when those tires are sometimes twice as wide?
Specialized was onto something with their Terra CLX EVO wheels, and Iām surprised those didnāt catch on moreā¦
2 Likes
The cassette is $650 
Wonder what this will cost once it gets down Force/Rival levels.
1 Like
Although I donāt plan to buy new wheels anytime soon, Iām happy to see more deep rim gravel wheels and the trend of wheels getting wider overall.
So the XPLR are basically deeper and wider 303 and 303s. Seem to be priced accordingly. For 32mm IW, hookless shouldnāt be an issue.
So i wonder when 13 speed for lower groups will come out?
I found the gear ratios after some digging: it is essentially a 10ā36 cassette where the 36-tooth cog is replaced by a 38-tooth cog and a 46-tooth cog slapped on. I really wish they made a 10ā39 cassette (10ā33 12-speed cassette ratios + a 39-tooth cog).
2 Likes
I disagree on rim widths for multiple reasons. In my experience, very wide rims with smaller tires are more prone to pinch flats, and there are reviewer reports indicating that they are having this issue. I think this is less of an issue on the road, and that aerodynamics are the predominant factor. Extra wide rims also expose sidewalls more making them more likely to cut, which is also generally a higher risk off road as well. I think that the fact that World Cup downhill and enduro racers are still running sub 30mm internal rims sometimes, and that most of them are still on 30mm is a good indication that there are drawbacks to rims getting too wide.
2 Likes
I do agree with you that a 1:1 ratio of inner rim width to tire width is far too much for off-road applications, but I think 25mm is a little bit small for 47-50mm tires. 
It depends a lot on the surface youāre riding on too.
1 Like
I think for up to 50, 25 is probably correct. Iāve run 35 and 38s on the 25s off-road, and I think that 40 is about the narrowest I want to run on them off-road. That being said, I think 28s on a 23 is a great combo
1 Like
The price of the Eagle Transmission components dropped 20 to 30 percents within a couple of months. If the same happens here the cassette will still be pretty expensive.
Edit: the cheapest old Sram Red xg-1290 12sp cassettes are around 200ā¬, which is about 50% of the list price.
Uh oh. My Reserve 34/37 wheels have IW of 23 & 22 and run 47 pathfinder pro.
Seem to ride just fine. What am I missing out on here?
The light bulb effect. wider inner width can keep the side wall more flush to the rim saving as many as 3w. Impressive I knowā¦
3 Likes
I think that to some degree this light bulb can be beneficial in off-road tire dynamics though. Factory racing motocross bikes have it, and they have a pretty substantial budget, and lots of support to optimize. I think what is not well defined is where that optimal balance is. Weāll see how gravel tires and rims develop, but I think they will end up somewhere between MTB and road, just like you might expect.
1 Like