hardtail mountain bikes

[Cole]

Jonathan, are you happy with your current frame? Would going up a size or two in it be worth it?

I've ridden no true DH/FR/XC hardtail frame, apart from my Le Toy 24, but even that is closer to the DJ end of the spectrum. Although, I did everything with that frame when I was younger and just pedalled my ass off and didn't care. Would maybe something on the older/cheaper end of the full suspension side of things be something you'd look at?

[jonathan]

I generally like my current frame but I know it's a size too small. I can't buy the exact same frame in a bigger size- Surly discontinued the OG Karate Monkey and my shop can't buy Surly stuff anymore unless I get someone to give me a bro-deal. so while I am thinking of getting a new frame, I am considering a whole new ride setup.

[cmc4130]

29er tires typically measure ~29.25" tall inflated. "26" tires typically measure ~26.25" tall inflated.

650b tires ("27.5" is absolutely a marketing term and nothing more) typically measure ~27"-27.25" tall when inflated. The wheel size change is minimal and makes very little difference when riding, most of the "improvements" on the new breed of 650b enduro bikes are due to changes in geometry, setup (including wide bars + short stem), and refined suspension technology.

For me, actually riding a MTB in the woods is 50% climbing and 50% descending. For that, I need a bike with enough room to get my weight forward while climbing, and then be stable while descending. Coming from bmx I used to think that a short TT was good so I can throw the bike around but that seriously hurt my MTB riding. I hated every Medium sized frame I owned due to the cramped climbing geometry, and now that I am on Larges my riding has improved as well.

DH racers, who ride 100% downhill at mach chicken speed, are even going as long as possible on their top tubes. The school of thought is progressing and geometry is changing to reflect that.

This is all my 2 cents and should not be taken as anything more than that.

Good points.  I don't spend a ton of time improving my climbing, so I realize a true xc/am bike is better for climbing. 

Not sure I can agree on DH bikes being as long as possible.  I've been renting all the latest demo bikes at the mountains every summer since 2009 and to me it seems like the "reach" difference is about the same as Dirt Jumpers, which run shorter than XC/AM bikes.   For example, compare the "Reach" on the TRANSITION TR500 to their other AM/XC bikes.  The XL is for the Downhill bike is shorter than the XL for the other bikes.  http://www.transitionbikes.com/2015/Home.cfm#0

I noticed that when I'm riding DH, I actually like a shorter frame (Medium) because it puts me behind the bottom bracket most of the time.  When you're going Downhill you do not want to be leaned way out forward.... It's a more upright Motocross stance.

[master]

I was talking specifically about World Cup level racers... They are going as long as possible. Longer frames plus offset headsets even for the average height racers. And as always, WC geometry trickles down into all DH bikes because going fast is the name of the game and nobody does that better than pro racers.

And I disagree about keeping your weight "behind the BB"... Centered weight will keep your front end planted, the last thing you want is to wash the front out in a turn due to too little pressure on the front tire.

[Admiral Ackbar]

master with the knowledge.

all mountain/trail/enduro bikes are a great example of the aforementioned trickle-down.

they have significantly longer reach, as well as front centers and wheelbases compared to just a few years ago. the nomad is a pretty good example of this, which has is longer just about everywhere than a full blown dh rig from just a few seasons ago. times are a changin' (and i need myself a fuckin mtb)

this is some epic thread derailment.

[cmc4130]

I don't ride BMX anymore. sorry. I have been doing everything else that's possible with a bicycle lately though.

I ride a "small" custom built Surly Karate Monkey 29er (1x9 gearing, 80mm squish fork, giant tires) even though most would say I should be on a size up for my height. maybe I prefer the smaller frame from years of riding little bikes. I find that I avoid a lot of the really "interesting" trails around here. the terrain has lots of gnarly exposed rock with some steep descents and drops and I hesitate to even go near that stuff. I have taken some of it a few times, but usually because someone led me out there and I could not find my way back home by myself.

so I want a bike that's more confidence-inspiring and I think all the marketing hype around 650B wheels is getting in my head. FS bike is not in the budget, so if I wanted a more capable HT, what have you bmx-gone-mtb guys experienced on 29"/27.5" tire-ed bikes?

How did this work out?

[jonathan]

I ended up getting a "large" (aka medium) 17.5" Soma Juice. it's about the same size as a 18" Karate Monkey of the same vintage. I wanted to get a sized-up KM but I was working at REI at the time and something had soured between REI and Surly, so we could no longer pro-deal Surly frames or bikes. (oddly enough, REI is now a Salsa dealer, which is owned by the same company.) anyhow, I was able to get Soma stuff through BTI. I have ridden it on places you probably know: BCGB, Walnut, SATN, and recently rode the Texas Chainring Massacre on it. it's single-speed most of the time, but I have a 1x10 setup that goes on it occasionally. I have ridden it with a Reba at 120mm, 100mm, and a Salsa rigid fork. I might enjoy something different, but I had very limited choices at the time. I don't think it's holding me back.

29" tires definitely do very well for me on Austin terrain. Glad I did not get a 650b. chucky trails and smaller wheels seems like a bad idea to me, especially on a singlespeed where every little inch of momentum you can save is crucial. I only wish the chainstays on the Juice were shorter. the shortest setting on the dropouts is 17.5", which is quite long by today's standards. I think getting up ledges and maintaining rear traction while climbing would be easier if I could take a link out of my chain, but that would mean just buying a whole new frame. I don't work in a bike shop anymore, so it's harder to justify paying full price for anything. I have written a bit about it on my blog, but i need to write more about this bike's trail capabilities- http://sidewallthorn.blogspot.com/

Update- the long chainstays on the Juice have always bugged me. Shopping for a new frame now.

[cmc4130]

I ended up getting a "large" (aka medium) 17.5" Soma Juice. it's about the same size as a 18" Karate Monkey of the same vintage. I wanted to get a sized-up KM but I was working at REI at the time and something had soured between REI and Surly, so we could no longer pro-deal Surly frames or bikes. (oddly enough, REI is now a Salsa dealer, which is owned by the same company.) anyhow, I was able to get Soma stuff through BTI. I have ridden it on places you probably know: BCGB, Walnut, SATN, and recently rode the Texas Chainring Massacre on it. it's single-speed most of the time, but I have a 1x10 setup that goes on it occasionally. I have ridden it with a Reba at 120mm, 100mm, and a Salsa rigid fork. I might enjoy something different, but I had very limited choices at the time. I don't think it's holding me back.

29" tires definitely do very well for me on Austin terrain. Glad I did not get a 650b. chucky trails and smaller wheels seems like a bad idea to me, especially on a singlespeed where every little inch of momentum you can save is crucial. I only wish the chainstays on the Juice were shorter. the shortest setting on the dropouts is 17.5", which is quite long by today's standards. I think getting up ledges and maintaining rear traction while climbing would be easier if I could take a link out of my chain, but that would mean just buying a whole new frame. I don't work in a bike shop anymore, so it's harder to justify paying full price for anything. I have written a bit about it on my blog, but i need to write more about this bike's trail capabilities- http://sidewallthorn.blogspot.com/

Update- the long chainstays on the Juice have always bugged me. Shopping for a new frame now.

Are there any 29'ers with less bb drop?  It seems like part of why 29'ers feel so glued to the ground is not just the long cs, but also the bb being way below axle level....

This guy did a custom 29'er dirt jumper.  Whatever the pros and cons of that, it's interesting that the bb appears to be at or slightly above axle level.
  http://plussizebmx.squarespace.com/blog/2012/4/3/bike-check-custom-dobermann-29er-dj-bike.html

[LeonLikesToRock]

FGFS have high BBs. http://breakbrake17.com/portfolio/bb17-serpent-29-freestyle-frame/ . It's easy enough to run a bmx hub in the back but you're limited in terms of brakes and you'll be sticking to rigid forks. Probably run for dicking about on and could do trails but no way you'd take it MTB riding.

[jonathan]

I ended up buying a used Niner ROS 9. I like it so far. It has an eccentric BB, so the center of the cranks can be mover aroud quite a bit. I started with the BB up/back for pedal clearance with rocks but I am trying it down/back now as well. It a singlespeed drivetrain, you only have a few options for BB positioning.