Rear hydration can be a precarious thing on mountain bikes as there is a lot of movement. I would just look at pictures of long distance race setups and try to emulate them to the degree possible with your setup. Hydration on long mountain bike races is a similar conundrum to long triathlons.

I've been mountain biking for years and have done a few 100 miler rides and races. A camelback is what most people use, myself included. I don't think I've ever seen a rear cage setup but I could be wrong. Trying to reach back to grab a bottle while riding bumpy and technical trails can be tricky. I would also think bottles would get launched on the trails. I have one bottle cage (I'm short so I can't fit two cages in my frame) and use that for my liquid nutrition. My camelback has my hydration. I will then refill at aid stops.

Find a hydration pack that fits you well and does not slosh around too much. USWE has some great options, Camelbak Chase vest, etc.

Just use a Camelback. You could put an underseat mount there but as others have mentioned, it could be hard to access while on a technical trail. Also it will get very dirty as anything tire throws up will hit it. Finally depending on size of bike and amount of suspension travel, it can make contact depending on holder. I have to use an underseat bottle holder on my wife's bike as it's such a small frame there are no bottle holders. She's also short so the bottle cage is pretty low due to short seatpost - tire will rub on bottle sometimes.

Camelbak (or similar).

Don't overthink it.

You WILL eject bottles, and if you don't, they WILL get covered with crud.

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float , hammer , and jog

Thanks everyone, Camelbak it is!

I use one with a specifically low bladder in the pack (can't remember the name now). Reduces pressure on the back and also (I think) allows a bit more air flow over the upper half of back which I like.

Either way, make sure you try it out for some rides before. The big 'learning' you'll need is to drink the right amount when you are 'blind' as you can't see how much the bottle is emptying. So very easy to over drink, or more likely to take on too little.

In addition to the above, if you find that you need even more hydration volume, you can get a frame bag (probably a half bag, assuming you're on a FS bike). I've been able to cram a 2L bottle in a half frame bag for bikepacking. The caveat is that it will make your bike heavier.

I agree with the others that a hydration pack is a way better idea than mounting a bottle to your seat. Backpack or lower back/hip style are both popular. Osprey and USWE are much more popular than the Camelback brand. I have done the saddle mounted bottle successfully, but I wouldn't do it again.

If you really want to avoid wearing a pack, the Revelate Designs Mountain Feedbag holds bottles really well on mtb and works with a fairly short stem. Bonus point for working well one-handed. I was pleasantly surprised when I needed a little more capacity to than my pack and bottle cage provided. It also has little spots for me tire plugs, gels, etc. I suppose you could do one on each side of the stem to get real crazy.

Ive raced Lead and Breck Epic and a number of NUE's in this - https://uswe.com/...tlander-pro-2l-white

works the best of any I have used, hands down.

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http://www.pbmcoaching.com
USA Triathlon Level 3 Elite Coach
USA Cycling Level 1 Elite Coach

When I MTB, I use a 3L reservoir in my Nathan or Ultimate direction pack. I don't have a "vest" style pack. I don't mind the full pack for MTB.

Can carry a tube, tools, phone, keys, gopro batteries, a space blanket, a rain shell / windbreaker, toilet paper etc. With the 2-3L of water I've found I couldn't care less if I have another pound of equipment on my back while riding. And I often decide I want to ride longer/farther than I planned, hence the light emergency supplies and larger pack. I've never thought "I wish I had a smaller pack." Maybe if I were racing Leadville I would.

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This exactly - as long as you can carry flat kit/tools/etc some other way. This pack is great - sits pretty high and doesn't bounce around. I used it for BWR North Carolina as well as a 50-mile mtb race. I find that I drink more due to the ease of drinking vs grabbing a bottle. As another poster said, water in hydration pack and liquid nutrition in bottles, refill at aid station.

you can put a very small flat kit in it - i use a tubolito and lever in there. carry co2 and DART in center rear pocket.

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http://www.pbmcoaching.com
USA Triathlon Level 3 Elite Coach
USA Cycling Level 1 Elite Coach

As other suggested a pack is probably the easiest method but I think they suck (maybe they are ok if you train a lot with one). The water tastes awful and warm, and it's like wearing a vest so you'll be warmer wearing one than without.

I've done 100 mile MTB races and just used 2 bottles (frame has 2 mounts), if my bike only had 1 mount, I'd probably put a second bottle in a jersey pocket.

^^^^ What he said^^^^ I've raced the full half a dozen times with one bottle on the bike and one in the jersey.

It depends... But with only one bottle cage, i would get a USWE outlander pro 2L. It is nice to be able to skip early aid stations and roll with a group if the race develops that way. Nothing sucks more than being in a group that is working well and having to stop to fill bottles and watch that group roll away.

I just did the lutsen 99er and ran 2 big bottles with fuel and a USWE with EFS. Didn't have to stop until aid 60, and rolled through aid 80 grabbing a coke. Kept my gels in a bento for easy access.

Just make sure the EFS doesn't plug the straw coupling... had to fix that on the roll.

Tools etc under the seat in a Silca matone. Make sure your multi tool has a chain breaker and keep a spare chain link in there.

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Off topic, can you describe Lutsen course? Dry or wet? Lots of sand? How is the climbing spread out? Overall a fast course or a plod? Thanks, considering as a Q for Leadville next year.

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Colorado Triathlon Company, CO2UT 2021, Crooked Gravel 2022, Steamboat Gravel 2022

its a lot of jeep road and maybe nordic trail - the fastest guys ride a HT if they have it. this year it was shortened a bit do to a bridge out.

Wet or dry really depends on the spring and weather leading up to it.

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http://www.pbmcoaching.com
USA Triathlon Level 3 Elite Coach
USA Cycling Level 1 Elite Coach

It is both dry and wet, some big bogs we had to go through this year, I was able to ride them when no one was in front of me. There can be long stretches of dry dusty road, lots of fast gravel. There was a new section of trail that was horrifically bumpy and if they use it again, I am not doing the race. No sand though.

There are 2 big climbs, one at the start and one at the end...


Last year was an abridged route as there were bridges out from spring flooding, with 13 miles less it was only 30 minutes faster than the previous year...

The usually 99er route has a long death march of a climb around mile 80, it is a series of stair steps that have blown me apart a few times now. You don't look at it and go, here comes a long climb, but it adds up and can really hurt.

The winning speed is typically right around 18 mph, it is by time the second longest Leadville quaifier. I did a 6:27 on my fat bike this year, last year I did 6:57 on the fatty. It is very much a pack race for the lead group, a teammate was in the lead group until Josh kept the pace high over the really bumpy trail and just gapped the group.

You have to start at the front of the field as the pace lines can open things up a lot, prepare to close a lot of gaps in pace lines, I burned too many matches trying to keep a group together, but I also didn't feel like pulling 15 people around for 6+ hours.

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Thanks for input! I live in CO and absolutely love climbing so no biggie there. I have friends in MSP area that might join me if I travel for Lutsen. I am guessing you were able to ride the bogs because of the fat tires?

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Colorado Triathlon Company, CO2UT 2021, Crooked Gravel 2022, Steamboat Gravel 2022

The bogs are mostly flooded out snowmobile trail so they are hard bottom, you just can't see the bottom.

I rode with a guy from Denver area in 2021 and he was struggling, wasn't used to the rolling accumulation of elevation, more used to the sustained steady climbing with plenty of recovery on descents. A lot of Lutsen is just punching up the last bit of a roller. Then just rolling on steady power, there just isn't a ton of chance to recover on course.

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