New Black Mountain Cycles "Mod Zero" replacing Monstercross Disc and Road+

[CMiller]

Looks awesome, and the sturdy frame matches the new larger tire clearance (27.5x2.25), I'll hopefully build one up in 2023 for dirt riding.

[unterhausen]

I know factories have had trouble passing those tests, even with relatively overbuilt frames. One-off builders don't have to pass them. Which is good, because the test is unrealistic and results in an overbuilt bike.

[oldpotatoe]

Originally Posted by hummus_aquinas

https://www.youtube.com/watch?v=Gd9P378edq4

The sun's over the yardarm somewhere....

[spoonrobot]

Originally Posted by unterhausen

I know factories have had trouble passing those tests, even with relatively overbuilt frames. One-off builders don't have to pass them. Which is good, because the test is unrealistic and results in an overbuilt bike.

I've often wondered the risk calculus behind modern testing. There doesn't seem to have been widespread injury causing events with broken steel frames and forks ridden offroad during the first 30 years of the MTB boom, so why in 2015 were the revisions so stringent? For bikes almost assuredly ridden mostly on pavement and buff gravel.

Are we far along that it's no longer common knowledge? Coming into bikes as adult a little more than a decade ago it was easy to see warnings for "death forks" for older road bikes, potential cantilever straddle cable/knobbie issues, and carbon fork warnings. But never saw anything about older steel MTBs and cross bikes.

Or is this mostly an issue relating to disc brakes and their effects on forks and steerers, backing up into frame design?

It's a shame, modern tires are so wonderful, while modern steel disc bikes are significantly worse than previous generations.

[charliedid]

Originally Posted by mstateglfr

My Fairlight Secan gravel frame has an 853 main trianagle with a DZB downtube. I am confident that it is overbuilt for anything I would ever do to the bike, since it has to pass the EN testing.
It's basically just thick at the head tube junction. Think triple butted tubing, basically.
10% more weight for 50% more strength at that junction.

I guess that is my question, if it's internal how is it different than butting?

[unterhausen]

Originally Posted by spoonrobot

I've often wondered the risk calculus behind modern testing. There doesn't seem to have been widespread injury causing events with broken steel frames and forks ridden offroad during the first 30 years of the MTB boom, so why in 2015 were the revisions so stringent? For bikes almost assuredly ridden mostly on pavement and buff gravel.

Or is this mostly an issue relating to disc brakes and their effects on forks and steerers, backing up into frame design?

Yeah, nobody that knows bikes had anything to do with the standards. Or they wanted something that was safe even if the manufacturer was not particularly good. And if there was industry involvement, they didn't care at all about steel bikes. You can find videos on the web of carbon-invested people showing how much better carbon forks are than steel for a single unrealistic frontal crash. But the tests don't require two things that I think are much more important than being able to survive hits: failed fork needs to be obviously failed. Fork needs to go through the frontal hit and then cycled to the equivalent of 30 years of riding. Steel will almost surely be fine, even bent. Carbon, we don't know, they don't do the testing.

But I must say I have seen some steel bikes that are probably marginal, and if they are used outside normal parameters they are going to fail. We do see bikes fail fairly often in the aggregate. I think a disc steel fork needs to be beefier than people want. Steerers do okay. The failed steel steerers I have seen have all been the result of bad workmanship. I'm not afraid to use a 1 1/8" steel steerer with discs.

[mstateglfr]

Originally Posted by charliedid

I guess that is my question, if it's internal how is it different than butting?

It isnt different, per Reynolds. Thats why if a gusset is needed, I would much rather see it be internal...so it isnt seen.

The butting is different from normal double butted tubing, to be clear.
38.1mm diameter DZB downtube 1.15/.85/.6/.85
34.9mm diameter DZB downtube 1.10/9./.6/.9

These are a couple butting examples of actual DZB downtubes.

[EB]

Originally Posted by mstateglfr

It isnt different, per Reynolds. Thats why if a gusset is needed, I would much rather see it be internal...so it isnt seen.

The butting is different from normal double butted tubing, to be clear.
38.1mm diameter DZB downtube 1.15/.85/.6/.85
34.9mm diameter DZB downtube 1.10/9./.6/.9

These are a couple butting examples of actual DZB downtubes.

Even assuming this is equivalent to the gussets, it's possible that the cost structure of the frame wouldn't allow tubing that would provide this function. BMC frames are bog-standard double-butted 4130 cromoly - switching tubing could very well increase the cost to a point that it would no longer be the thinking person's Surly.

[d_douglas]

Out of curiosity, how big of a 700c tire would this bike fit? Also, is that steel fork with a tapered steerer?

I have always liked the concept of BMC bikes, so when Mike designs anew, I tend to read his descriptions. I don't really dig the giant stack height of this bike - aging as I am, I still like a bit of saddle to bar drop on my drop bar bikes - even for offroading.

[EB]

Originally Posted by d_douglas

Out of curiosity, how big of a 700c tire would this bike fit? Also, is that steel fork with a tapered steerer?

I have always liked the concept of BMC bikes, so when Mike designs anew, I tend to read his descriptions. I don't really dig the giant stack height of this bike - aging as I am, I still like a bit of saddle to bar drop on my drop bar bikes - even for offroading.

Agreed, I liked the stack height of the original Monstercross canti - he raised the stack a lot on his more recent designs in response to his buyers who kept running 4 to 5cms of headset spacers with riser stems.

Steel fork is a straight steerer, so needs an appropriate lower cup. Biggest 700c tire it can fit is still 50-ish, so you only get the 2.25" clearance with 650b.

[mstateglfr]

Originally Posted by Eli Bingham

Even assuming this is equivalent to the gussets, it's possible that the cost structure of the frame wouldn't allow tubing that would provide this function. BMC frames are bog-standard double-butted 4130 cromoly - switching tubing could very well increase the cost to a point that it would no longer be the thinking person's Surly.

Yes the cost of using an internal gusseted tube could exceed welding chunky plates onto the outside of the tubes and that cost difference could push the frame to a point that Mike doesnt like.

As for the tubing being 'bog standard 4130', he has mentioned thru the years on his blog that it is .8/.5/.8 and heat treated. That is certainly more refinement than 1/.7/1 or .9/.6/.9 untreated tubing.
He also mentioned it is rolled.

[Mike Lopez]

While we were bringing the Ouzo Pro to market we built and tested (broke) roughly 400 forks characterizing the failure modes and designing the layup to “unzip” at the seam on the side of the crown after a defined impact event. The fork body did not separate from the steerer but the rake changed a mm or so (permanent deformation) and there was a visual indication that they had failed. Point is…they didn’t fail catastrophically through most impacts that wouldn’t throw the rider off the bike anyway.

And…we did in fact do multiple combinations of tests on the same fork. Fatigue after impact, max load after impact, etc. We, the bike riding composites guys that designed & built them thought about things like that.

Regarding Mike V. He’s been designing bikes & frames professionally for a couple decades and he knows how to make products that are safe, work well, and are affordable. And, although it’s been a long time, he’s a hell of a good rider and genuinely nice guy!

Originally Posted by unterhausen

Yeah, nobody that knows bikes had anything to do with the standards. Or they wanted something that was safe even if the manufacturer was not particularly good. And if there was industry involvement, they didn't care at all about steel bikes. You can find videos on the web of carbon-invested people showing how much better carbon forks are than steel for a single unrealistic frontal crash. But the tests don't require two things that I think are much more important than being able to survive hits: failed fork needs to be obviously failed. Fork needs to go through the frontal hit and then cycled to the equivalent of 30 years of riding. Steel will almost surely be fine, even bent. Carbon, we don't know, they don't do the testing.

But I must say I have seen some steel bikes that are probably marginal, and if they are used outside normal parameters they are going to fail. We do see bikes fail fairly often in the aggregate. I think a disc steel fork needs to be beefier than people want. Steerers do okay. The failed steel steerers I have seen have all been the result of bad workmanship. I'm not afraid to use a 1 1/8" steel steerer with discs.

[thegoldfi]

If the Mod Zero has anyone hyped to sell their 53cm MCD, let me know. I am on the hunt for one!

[tctyres]

Originally Posted by thegoldfi

If the Mod Zero has anyone hyped to sell their 53cm MCD, let me know. I am on the hunt for one!

Not exactly what you want but ...
Mike Varley sent an email a week or two ago to his "interested customers" list that the La Cabra and MX canti will be coming in sometime in the spring. He's doing everything he can to get frames, and it seems to be stressing him out.

Mod Zero is going to be 2023, according to his site.

[David Benson]

Originally Posted by batman1425

You can run a straight fork if you want, just need the appropriate cups. The 44mm HT gives you options to run tapered if you want to, but doesn't force you to do it. Plus straight tube, disc carbon forks are going to become pretty rare.

If you use a Cane Creek headset all you need is a 52/30 crownrace