NSMB - 2020 - Hardtail Thread

Posted by: JBV

so since you guys are the HT experts, riddle me this: i read a lot of comments about how stiff this that and the other HT frame is. lots of grumbling. i'm confused. aren't hardtails stiff and boardy in the back end? like, all of them? what am i missing?

are some of them 'plush'? are some smooth riding and forgiving? the one i'm considering, Commencal HT in plump wheel size is aluminum and i imagine, very stiff. with fat tires and inserts ridden at low pressure, i would think that the stiff factor would be well mitigated but i don't have experience first hand.

so is it the frame, the tires, the wheels, or something else that makes an awesome hardtail?

Ideally it's both. I've had hardtails that were too compliant in both planes and that wasn't good. My latest ti hardtail finally got the mix right for me. It's super compliant vertically (which is partially due to the ti) but it's not overly compliant laterally (thanks to big tubing diameters, wall thickness and bracing). It's pretty amazing to ride a HT hard through gnar and feel it conforming predictably to the terrain. I don't get when reviews talk about HT frames being crazy stiff.

Posted by: JBV

can any of you provide a list of top 3 'compliant' hard tail frames out there?

I could tell you some that would have the right flex for me, but unless we are pretty similar that may not mean they'd be good choices for you.

Posted by: JBV

can any of you provide a list of top 3 'compliant' hard tail frames out there?

Bikes that i have personally ridden.

This will be an unpopular option but my Chromag Wideangle is not compliant at all. First steel frame i have ridden that is aluminum level stiff. As all Chromag bikes use the same tube set i fear that are all mega stiff as Chromag uses a super burly tubeset to avoid breakages. Probably why a lot of Chromags run fatter tires and CushCore 

The Norco Torrent has good compliance.

My old 2008 Cove Hand Job is a very compliant frame.

I am honestly looking at getting a Marino frame built to my spec as the tubeset looks to be a bit lighter.

Posted by: heathen

Posted by: JBV

can any of you provide a list of top 3 'compliant' hard tail frames out there?

Bikes that i have personally ridden.

This will be an unpopular option but my Chromag Wideangle is not compliant at all. First steel frame i have ridden that is aluminum level stiff. As all Chromag bikes use the same tube set i fear that are all mega stiff as Chromag uses a super burly tubeset to avoid breakages. Probably why a lot of Chromags run fatter tires and CushCore 

The Norco Torrent has good compliance.

My old 2008 Cove Hand Job is a very compliant frame.

I am honestly looking at getting a Marino frame built to my spec as the tubeset looks to be a bit lighter.

My rootdown was terribly stiff. I actually think frame design matters more than material. My carbon chameleon is much more compliant than my steel chromag was which runs opposite to the steel is real movement. It's more accurate to say steel can be real but doesn't have the same ring to it. 😋

Posted by: Kenny

Posted by: heathen

Posted by: JBV

can any of you provide a list of top 3 'compliant' hard tail frames out there?

Bikes that i have personally ridden.

This will be an unpopular option but my Chromag Wideangle is not compliant at all. First steel frame i have ridden that is aluminum level stiff. As all Chromag bikes use the same tube set i fear that are all mega stiff as Chromag uses a super burly tubeset to avoid breakages. Probably why a lot of Chromags run fatter tires and CushCore 

The Norco Torrent has good compliance.

My old 2008 Cove Hand Job is a very compliant frame.

I am honestly looking at getting a Marino frame built to my spec as the tubeset looks to be a bit lighter.

My rootdown was terribly stiff. I actually think frame design matters more than material. My carbon chameleon is much more compliant than my steel chromag was which runs opposite to the steel is real movement. It's more accurate to say steel can be real but doesn't have the same ring to it. 😋

Design is 100% important. Carbon can also make a very complaint frame.

I think Chromag should put a little more tech into there steel tubeset and make it more compliant. The tubes are just over built for strength when I don't think the average rider needs that much strength. Maybe the old Sakura frame should make a come back with a nice Reynolds or Tange tubeset

I've enjoyed reading this thread over the past several months as I ventured along my own hardtail journey. Thanks a bunch for all of the opinions and information.

Some background: We get an absolute ton of snow for 6 or 7 months of the year in this part of the Rocky Mountains. As such, fat bikes are the tool of choice in the winter months and their popularity only seems to grow. I have the spent the previous few years on a fat bike, beginning on more heavily trafficked trails and eventually gravitating towards more of the longer, back-country adventures I'd typically find myself on in the summer months. I found the novelty of the fat bike and the limited type of 'riding' it affords a person got stale fairly quickly. As I was spending more time pushing/carrying a bike to the top of something steep (steep enough to make the snow accumulation moot), the fat bike itself became irrelevant. 

So this year meant selling the fat bike in favour of an all-season hardtail. Something on which I could run a 29" tire in the summer (for those opportunities to refresh some of the local laps), and a 3" tire for the winter months. I had the goal of making it almost 100% parts-compatible with my Madonna trail bike, and here's how it ended up:

I tried to keep the build somewhat budget friendly while still maintaining compatibility with my trail bike. The hubs and rotors are identical between the 29" and 27.5" wheelset, so wheel swaps are a breeze. We've had ridiculous temperatures over the last week, causing most of the already-fallen snow to disappear and I've found it pretty convenient to throw the summer wheels in the car and switch them out after an initial 'survey lap'. 

Here are the parts I used:

• Marzocchi Z1 Coil @ 160mm. It's really simple to move the travel to 170mm if I want to maintain the BB height between wheelsets, but I haven't found that necessary.
• Shimano M6100 drivetrain. I'm really happy with the cheap Shimano. I do use an XT shifter to keep things feeling the same between bikes. I do like to adjust the clutches on these things, but don't do it often enough that having to remove the cap is that big a deal.
• Shimano M6120 brakes. Again, very happy with these. Not quite as strong as the Saints on my trail bike, but I'd be happy with these brakes on anything. Plus I can use the same pads in both, meaning I only have to keep a few spare sets of D02S pads on hand and I'm covered. 
• OneUp v2 dropper @ 180mm. Again, same dropper on both bikes. I sometimes have issues with the cartridges on these, so it's nice to have a spare.
• Wheels are DT XM551 rims (40mm internal) on DT 350 hubs. I've used DT 350s on everything for years and have never had an issue. Buying the wheel parts separately and building them myself leads to a very cheap, very high-quality end result. It's crazy what DT parts can be had for by the frugal, online shopper. 
• Bars and stem are the cheapest compatible option I could find... I cut all my bars to 760mm as some of our trails don't give you much more space than that. 

Some thoughts:

These 3" wrathchild tires have a ridiculous amount of grip on ice, but I think I'll need an 'intermediate' option for shoulder season days with mixed conditions. Took all of 1.5 rides to slash a fair-sized hole in the soft, winter rubber. These will be set aside for days further into our endless freeze/thaw cycles. 

As for the frame, previous posts are certainly correct about the stiffness. Our trails are incredibly raw and rough and it has taken some fine tuning to find that balance between psi, speed, and my ankles holding together. But, all that aside, this thing is so much damn fun. The geometry is similar enough to my trail bike that there was zero learning curve involved. 

Thanks again for the existence of this thread. It certainly helped in my decision to go full-hardtail.

Posted by: dirtreynolds  

Nice looking Rooty. Having a couple wheel sets is a smart way to get a lot of versatility out of a bike like this. Good move.

My rootdown was terribly stiff. I actually think frame design matters more than material. My carbon chameleon is much more compliant than my steel chromag was which runs opposite to the steel is real movement. It's more accurate to say steel can be real but doesn't have the same ring to it. 😋

Have you ridden other Chromags? Wondering how the Rootdown compares to the Stylus? I found the Stylus to be pretty compliant for a hardtail and have my eyes out for a rootdown now....

Posted by: MaxRockatansky

My rootdown was terribly stiff. I actually think frame design matters more than material. My carbon chameleon is much more compliant than my steel chromag was which runs opposite to the steel is real movement. It's more accurate to say steel can be real but doesn't have the same ring to it. 😋

Have you ridden other Chromags? Wondering how the Rootdown compares to the Stylus? I found the Stylus to be pretty compliant for a hardtail and have my eyes out for a rootdown now....

I believe all steel Chromag share a tube set. My Wideangle is super stiff

Can confirm. My Wideangle beats the shit out of me.

Posted by: JBV

so since you guys are the HT experts, riddle me this: i read a lot of comments about how stiff this that and the other HT frame is. lots of grumbling. i'm confused. aren't hardtails stiff and boardy in the back end? like, all of them? what am i missing?

are some of them 'plush'? are some smooth riding and forgiving? the one i'm considering, Commencal HT in plump wheel size is aluminum and i imagine, very stiff. with fat tires and inserts ridden at low pressure, i would think that the stiff factor would be well mitigated but i don't have experience first hand.

so is it the frame, the tires, the wheels, or something else that makes an awesome hardtail?

The frame makes a big difference, but other factors also contribute.

I've got two (now somewhat vintage) hardtails, both with 140mm forks, 26x2.35s. and have primarily run Syncros 27.2 Ti seatposts (until recently :( ) whose flex makes a big difference vs. aluminum posts for seated pedaling over chatter. Although both started with Kenda Nexcavators, the Blizzard has moved on to Schwalbes (MM up front, Nic in the back because MMs won't clear the chainstays) Both started with WTB Silverados (Ti rails on the Obed, CroMo on the Blizzard) the Blizzard has also had several different vintages of Chromag Trailmaster DTs.

Titanium Litespeed Obed aka Cove Hummer (18")

4130 Rocky Blizzard LT (19.5")

I think the steel Blizzard LT actually has a smoother ride. The square-swaged seat/chainstays may contribute to the Obed's rear end being vertically stiffer than usual for a Ti bike. Other possible contributors:

• Blizzard - plush coil Marz 44 vs. Obed - very linear Magura Thor air

• (I've put enough miles on both bikes that the Blizzard is on its second 44 and the Thor is awaiting bushing replacement)

• Blizzard - 31.8 butted Ti bars vs. Obed - very flexy 22.2 straight-gauge Ti (which may take some of the edge off the Thor)

• Blizzard - bladed spokes in the rear wheel vs. Obed - straight-gauge spokes

• Blizzard - North Shore XS cranks on square taper BB vs. Obed - M970 XTR

As a super-nerdy aside:

The cranks are a form of suspension that I think is overlooked for hardtails. I don't think you want crank-arm flex (worst case, arms hitting chainstays, but also losing energy to lateral flex that can't be recovered), but I think torsional flex (not bending) of the crank spindle might not be such a bad thing. Picture yourself riding with your pedals even on rough terrain and torsional wind-up of the spindle allows the crank arms to go from being parallel to each other ( - -) to a subtle inverted V shape ( / \ ) damping out some of the force of an impact and preventing it from being transmitted into your feet. If the torsional flex was large enough, it might also even out pulsations in peak pedaling force by winding up only to spring back and release some of that energy in the dead part of the stroke. The challenge would be to get the torsional flex without getting bending flex (which would be hard on bearings) A smaller spindle with outboard bearings might give a good torsional wind-up while limiting bending and keeping shear strength up (the weak point of my square-taper). A possibility for a Chromag Crank Concept... XD?

After all that, I don't think it's possible to build an aluminum hardtail with nice compliance but good fatigue resistance. I haven't ridden a ton of aluminum hardtails, but every one I have ridden was a filling-removal machine.

Posted by: WeTYC...

As a super-nerdy aside:

The cranks are a form of suspension that I think is overlooked for hardtails. I don't think you want crank-arm flex (worst case, arms hitting chainstays, but also losing energy to lateral flex that can't be recovered), but I think torsional flex (not bending) of the crank spindle might not be such a bad thing. Picture yourself riding with your pedals even on rough terrain and torsional wind-up of the spindle allows the crank arms to go from being parallel to each other ( - -) to a subtle inverted V shape ( / \ ) damping out some of the force of an impact and preventing it from being transmitted into your feet. If the torsional flex was large enough, it might also even out pulsations in peak pedaling force by winding up only to spring back and release some of that energy in the dead part of the stroke. The challenge would be to get the torsional flex without getting bending flex (which would be hard on bearings) A smaller spindle with outboard bearings might give a good torsional wind-up while limiting bending and keeping shear strength up (the weak point of my square-taper). A possibility for a Chromag Crank Concept... XD?

In my personal experience and perception, I rarely have my weight completely evenly spread between the two pedals when riding over bumpy terrain -- I'd say this is due to the cranks being roughly horizontal but my legs being in different positions, of slightly different strength, and so on. So when I absorb hits from the rear with my legs, the cranks will move around anyway. I don't know if your suggested torsional flex approach would make a noticeable difference in that situation. That said, I tend to push more of my weight into the fork than on a FS bike when riding the hardtail, and it's steel, with outboard bearings and a 24mm spindle. Regarding pedaling, from your description it sounds like oval chainrings try to solve the same issue (successfully in my opinion, my hardtail is easier to pedal on steep, loose surfaces in 32:18 with an oval).

Posted by: WeTYC...

After all that, I don't think it's possible to build an aluminum hardtail with nice compliance but good fatigue resistance. I haven't ridden a ton of aluminum hardtails, but every one I have ridden was a filling-removal machine.

I agree completely.  Steel or Ti is really the way to go.  

Btw, awesome bikes!

Unfortunately flex characteristics are very hard to gauge without actually riding the bike in question. I'm a fan of steel bikes because they can be both affordable and flex nicely, but they can also be super stiff. Bike reviews can be helpful if the reviewer is a similar weight as you, similar riding style and is knowledgeable/aware about the subject of frame flex. Other than my custom Daambuilt I've just made the best educated guess I could about hardtail frames and then accepted the fact I'd try and sell some of them. Over the years I can recall 3 frames that were unpleasantly stiff so they lasted a few months before I moved on. I feel like I am getting a bit better at figuring this out remotely since most of the frames I am interested in are not available for test rides. Although after my experiences with getting a custom hardtail made part of just wants to keep going that route so I can just spec exactly what I want and not have to compromise.