Apr 5, 2022

This week Craig and Randall continue the discussion on the considerations for Craig’s custom gravel frame build. We dig into the history of Reach and Stack, the meaning of BB drop and how different materials afford different options and considerations for construction.

Episode sponsor: Therabody RecoveryAir JetBoots

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Automated Transcription, please excuse the typos:

In the Dirt #29

[00:00:00] Craig Dalton: Hello and welcome to in the dirt from the gravel ride podcast. My name's Craig Dalton. I'm your host. And I'm going to be joined shortly by my cohost Randall Jacobs. In the, in the dirt episodes, Randall and I take an opportunity catch up on everything going on in gravel, cycling. Uh, Everything you need to know in between our long form interviews on the gravel ride podcast

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Would that business out of the way, let's jump into this week's episode

[00:03:46] Craig: Hey Randall, how you doing?

[00:03:49] Randall: Well, a little bit under the weather here in Boston, but hopefully we'll be recovered before I head out your way in a couple of days. Are you?

[00:03:57] Craig: to see you got to get over this cold.

[00:03:59] Randall: Yeah. Yeah. Yeah. I'm actually hoping to see a lot of or at least a few of our listeners as well. We got Seattle coming up.

[00:04:07] Craig: Yeah, that's a good place to start. Yeah, so we're, we're getting we're both of us are going to be at Seattle this year, which is exciting. I think we did sea Otter together two years ago. That's on,

[00:04:16] Randall: Two or three years ago. Yeah. Whenever you know, and that, that, that innocent pre COVID era

[00:04:23] Craig: That's

[00:04:23] Randall: when I was still living in the bay area.

[00:04:26] Craig: For the listener that may not be in the region or may not have heard of seawater. It's actually an event that's been going on in the Monterey bay peninsula area since 1991 mountain bike started out at because a mountain bike festival had added on road racing criteriums. They had a cyclocross race at one point observed trials.

Like you name it. If it's done on two wheels, they've been doing it at the sea Otter classic for you.

[00:04:53] Randall: it's also, become I believe the, the most important trade show in north America with the, you know, with the folding of the M oh, Interbike. Yeah. And in fact I've always felt that it was a much more enjoyable experience than Interbike because you have this kind of festival environment. So people are there.

You have general audience general riders who were there to participate in the events and to, you know, meet up with each other and to walk around and see the booze and so much more you know, rider friendly and so on. So I'm excited to get out there. it's been a long time.

[00:05:23] Craig: it's also really interesting to me to see the merging of all the different cycling cultures, because you've got a big downhill contingent and dual slalom contingent with their slam seats and 10 inch travel bikes and full face helmets. And then you've got like the Legion criterium squad rolling around doing the CRA you know, the circuit.

[00:05:44] Randall: Yeah. and I, I'm not sure. I would imagine the, the UCI cross-country race is still going on there. That was the only time I ever lied up at a, at a UCI level race, which was a cool experience. So you get to see some of the international level pros.

[00:05:58] Craig: Yep. Yeah. And it's it's right at the Laguna Saker Raceway. So it, some of the, I think a lot of the courses finish on the car racing, motorcycle racing track, which is kind of a cool.

[00:06:09] Randall: Yeah. Yeah. Yeah.

[00:06:10] Craig: Yeah. And this year they've added this is the kickoff of the lifetime grand Prix, which is a six or eight race series with a $250,000 prize.

So I know a lot of professional athletes are sort of jazzed and keying in on this, and it's a, don't need to get into the series and I'll get someone from lifetime on to talk about it. If you haven't heard about it already. But what's interesting to me is they're doing mountain bike racing and gravel racing as part of the same series.

So it's really, I, in my mind, ideally pushing athletes to have capabilities in both domains.

[00:06:45] Randall: I mean, there does seem to be a very natural kind of merging of these two disciplines in that gravel bikes have gotten evermore capable. And cross-country bikes have actually gotten radically more capable to we've transitioned to down country. Cross country courses have gotten more technical. And so, you know, everything is kind of shifting a little bit.

I certainly love the, the Mo the underbite mountain bike experience on the gravel bike.

[00:07:07] Craig: they haven't made this rule, but I would kind of love it if they force the athletes to race one bike. So pick your poison, gravel bike on the CrossCountry courses, cross country bike on the gravel courses. You got to decide at the beginning of the season.

[00:07:22] Randall: I mean, honestly, I remember I've done seawater twice and I remember one year they had the long course and on the long course, it was only one section that I recall. Even really requiring suspension. And so if I had had a gravel bike at the time, I probably would have crushed it. Everyone was riding flat bar, you know, suspended mountain bikes.

And there was this one kind of breaking bump challengers section that I recall. And then the other year they had it such that it went through Laguna Saika like five or six times. They were trying to make it very spectator friendly. And in that case even more so, cause there's just, you know, you're spending so much time on the road that whatever time you lose on that, Slightly Chandra resection.

You're more than making up for.

[00:08:04] Craig: Yeah, that might've been my jam as well. Cause my Achilles heel was always climbing. I could never climb with the best of them. I'm a decent descender. So yeah, the gravel bike probably would have helped me stay closer to the front of those races.

[00:08:16] Randall: so, and you're going to be doing the, the NV sponsored gravel ride on Saturday, right?

[00:08:21] Craig: Yeah on Saturday. Yeah. So there's a couple for anybody in attendance. There's a few gravel like casual gravel rides, and there's also a gravel event on Sunday. So definitely bring your bike and enjoy some of that gravel.

[00:08:36] Randall: So let's talk about the event that we're getting together.

[00:08:39] Craig: Yeah. So we're excited. Yeah. We're going to get together the ridership community and the gravel ride podcast community and the thesis by community, along with our friends over at scratch. So scratch has got a booth and we'll get we'll. We're meeting up over there at 3:00 PM on Saturday, April 9th.

[00:08:57] Randall: We'll probably be hanging out there for awhile. So if you can't get there right at three definitely stop by later the day, but we'll have some, some beverages, some music we'll have some special guests, a few athletes. The famed rice cake maker Allen Lim he was on the podcast before,

[00:09:11] Craig: That's right. Dr. Alan Lamb, one of his threads of fame is rice cake cooker.

[00:09:16] Randall: I think he also has been involved in training some, some elite athletes and he might've started scratch as well, but definitely rice cake makers probably is his biggest claim to fame there. And then we'll have a raffle and an exciting product line. Which I'll just leave it at that. At this point.

Anyone who's in the ridership will probably know what I'm talking about here. Cause I've dropped a few hints there. But it'll be really excited to get the, do the first pre-launch reveal of this new line that we've been working on for some time.

[00:09:42] Craig: Yeah, I'm excited for you to talk about that publicly as someone who's sort of been in the background, just hearing whispers of what you're doing, and then starting to hear more specifics from you directly. It's super exciting. And like, I appreciate how much you put into the space and how. I thought you put into these products that you bring to the world.

[00:10:01] Randall: Thanks bud. Yeah. and I definitely feel grateful to have kind of the one, like the supportive a community. They provided an immense amount of very useful feedback in, in the development and validation process. And then also just really great team and business partners. And so on that we've been co-developing this with so more on this in future episodes.

We'll do a one-on-one episode where we nerd out about how things are developed. But Yeah. come visit us at three o'clock on Saturday at the scratch labs with

[00:10:29] Craig: Super excited to run into any listeners and ridership members out there really like it's I feel like it's been a long time coming for us to do a little get together and hopefully if trends continue, we can start doing some of the ridership group rides around the world.

[00:10:44] Randall: Exactly. Yeah I'll be starting some in the new England area and I'm looking forward to flying out again to the bay area, to do a big event with you. Maybe sometime.

[00:10:53] Craig: Yeah, that

[00:10:53] Randall: Right around Mount mountain, where we used to ride together so much.

[00:10:56] Craig: A hundred percent. So the last episode in the dirt, we were talking very specifically about a new custom bike project that I've been working on for the listener. Just to bring you up to speed. I got to fit in January and it's just started to highlight some of the things. Some of the challenges I've been having with my boss.

In riding the bike, and this is not something new I've I sort of experienced this early on in my cycling career. And at one point I had a custom Brent Steelman road bike made for me. He's a pretty storied Northern California builder, probably best known for his cyclocross work. But anyway, I had the custom bike experience, but it was, it was kind of.

At that time, the one thing that nagged me and I realize now that this is sort of not the right way to even be thinking about this particular problem, but every road bike I ever got in front of what's a 56, 56. So 56 CT of 56, top two. And the one thing that felt to me like it didn't fit well. Was that 56 top tube.

So I said, Do whatever you want. I just want a 55 centimeter talked to, and it did solve the problem to a degree, but it wasn't really the solution to the problem, but it did feel amazing to get on that bike for the first time.

[00:12:12] Randall: When you also kind of hearkening back to the days when, when we talked about, you know, seat tubes and top tubes as a primary you know, driver of, of frame fit, because they were always coming in at roughly the same angles versus nowadays they're coming in at all different sorts of angles with compact geos and so on.

So, but the gist of like your bike was too long, you're, you're a pretty leggy guy.

[00:12:34] Craig: So that's, that's really interesting. You say that. So was it not, not the fact that I'm a lucky guy and thanks for noticing that, but more about the sort of, are you saying the story of that geometry back in that era or where the tubes were coming in there just wasn't a lot of variability. So the concepts of stack and reach weren't necessarily in bike design for an Acular.

[00:12:56] Randall: Correct. Yeah. Yeah. So you'd generally the top tube would be, you know, relatively. And then, you know, at some point you started seeing more compact geos where that top tube is sloped and that had various various benefits in terms of stand over height and you know, potentially, you know, frame stiffness and so on.

But it also meant that, you know, your seat tube and your top tube were not really particularly good proxies for how the bike would fit. And so we need a new proxy and that's where stacking reach came into play.

[00:13:22] Craig: Okay. Yeah. And I mean, you can imagine like, obviously like with mountain bikes, having super slipping top tubes and all kinds of things like that, but stacking reach, like you had to come up with some sort of measurement that people could hang their hat on.

[00:13:35] Randall: Yeah. Yeah. Yeah. So with the bike that, where we've designed for you now, I mean, you have, remind me you're just 5, 9, 5, 10.

[00:13:44] Craig: Yeah. Just five, nine and a half.

[00:13:46] Randall: Five nine and a half, and I'm five 11 and you and I run the same satellite and I run a pretty high and forward satellite too. And so you were on the medium our, our medium, I ride our, our large OB one.

And one of the things that you, that, you know, I always noticed with you is you always had your, your stem. As high as possible and flipped upward and so on. And so this new build is going to really address, you know, first and foremost is stack issues. You've won a higher bar for some time.

[00:14:13] Craig: Yeah, exactly. I mean, that, that was the most sort of visceral. The thing I had after this fit. And it's something that was very, it was known to me and my body. Like I've, I've lost flexibility. I never had a ton of flexibility. And the fitter said, well, you've, you know, the position of your saddle height versus your bar height is that of a pro tour road cyclist.

And I had this like, The eight millimeter drop or something, and he's like, we really want to get you more around four. So it was, it was interesting. And I encourage people to go back to episode 28, if you're interested. And I don't purport to believe that you care about my personal fit, but I'm trying to eat this out with Randall and both these two episodes, just to give the listener something to think about as they go forward in their cycling career, because there's, there's tons of things you can do around your existing bike to modify them.

I came to some limitations because I'd already configured my thesis. I'd already cut the steer to buy the fork. I couldn't bring the bars up any further unless I had an obnoxious, jacked up stem. So I came to the conclusion. Hey, given this opportunity, why don't we, why don't I look at fabricating a bike specific to my needs?

So we had episode 28, which is the last in the dirt episode, and we talked a little bit about bike geo calculator, and it was pretty easy. Like it's a great tool. And I saw lines where the new frame would be an and I looked at that, that stack height and the higher head tube, and I was like, great, this is going to fit.

But then as we worked with the building, And got into CAD. There was all these things that have just taken a lot of time to muddle through. And part of it is fabricating with metal versus carbon. Part of it is like things that, all things aren't equal. You really have to think about what, what is your north star in the fit and work around that versus what is any particular tube length or dimension?

[00:16:12] Randall: And then you have parts availability, right? So you want to achieve something, but the, you can't find a part that allows you to achieve it, even though it exists, it doesn't exist in the timeframe that you need it.

[00:16:22] Craig: Yeah, yeah. A hundred percent. So I mean, a couple of the areas we've been keying in on, I mentioned, I think in the last episode, like I had this desire to be able to accommodate as big attire as possible. But then when, when you talk about the practicality of welding, the rear end, all of a sudden, a bunch of things come into play because you can have a really long stay to accommodate that.

But I didn't really want a really long stay. I've been pretty darn comfortable on my last two bikes with a 420 20 millimeter seat stay. And like the idea of going out to 4 45 or something like that, just didn't sit well with me.

[00:17:01] Randall: Yeah.

For 20 chains day and yeah, and it just makes it so that the, the front end doesn't want to come up as much. It, you know, it slows the handling. It's a longer wheel base. But you know, it's appropriate to go. It can be appropriate to go longer for more of a dirt focus machine versus a, a, a one bike that is also being asked to be a spirited road bike.

That's kind of the direction that we went with this thing.

[00:17:23] Craig: Yeah, I think that's a great point. Like there comes a decision point in any gravel cyclist's life when you're purchasing a new book. To just think about like, where do you fall on that spectrum? And when I look at the writing, when I look at what I was conceiving of with my thesis, it's like, I want something that's Zippy on the road and super capable off-road, but can kind of slot that ground between.

But the reality is, you know, my writing is 95% off road.

[00:17:52] Randall: Yeah. Yeah. Yeah. And you already have a thesis that you're you've. So this isn't adding to your stable.

[00:17:59] Craig: Exactly the thesis isn't going anywhere. So while this bike may, the new bike may rarely get road tires on it. The thesis will have both road. And I still think that thesis is an amazing, like race, bike, and it's been so good for me. It's so capable. I'm excited to have, I mean, it's just an absolute luxury to be able to have two bikes and like in the garage,

[00:18:19] Randall: Yeah.

but the, the added capability of this new machine is, is definitely going to be you know, meaningful like that extra tire clearance. So maybe we start there. So this tire clearance for like full tire clearance. So at least six millimeters all around for 60, 50 by two points. Front and rear, and you could probably squeeze something a little bit bigger upfront.

We were fortunate in that we were able to find a fork that had the offset that we wanted specifically. We reached out to dry broom and over it open cycle and he had some U-turn forks kicking around. So that's a 50 mil offset and

also a 3 95 axle, the crown. So just throwing numbers out there.

What does this mean, Zack? So the CR offset is. Basically the distance from the axle from the, the line that goes through the steer tube. So it's going to be offset, you know, the axle is offset forward from that, and more offset is going to make the steering more responsive, but it's also going to increase your, your front center, the bottom bracket to the front axle to reduce risk of total.

And that was, that was a concern, given that your you're wanting a shorter bike, that's fitting bigger 700 seat tires.

[00:19:32] Craig: Yeah. Yeah. And it also, so that does wheelbase come into play with those dimensions as well? The overall wheel base.

[00:19:38] Randall: Absolutely. Yeah.

So, you know, the, the well, so with the offset, so we had the increased offset which. With the same head angle, as you increase offset, it's going to decrease trail and you know, the, the less trail you have, the snappier, the handling is that in turn allowed us to slack it out the head angle a little bit without radically slowing down the handling.

So we went from a 72 degree head angle on your thesis, which is more of a, like an endurance road in a more kind of racy. Gravel front-end to a 71.2, which is still actually on the sportier side especially for this new class of gravel bikes that have seemingly gone towards, you know, even slacker even longer.

And overall we got the, the front center up, you know, 18 millimeters. And so those. Taller 700 C tires that you might run are not going to be an, an issue for you in terms of tow overlap. You're also going with 2.5 millimeter shorter cranks, which helps as well. And that, that opened up another opportunity with the bottom bracket height.

[00:20:42] Craig: Yeah. So before we get into BB height, you know, it was interesting. Really digging into the forks situation. Again, a lot of times you're bike. Well, all the time your bike comes with a fork and you don't really think about all these things, but once we were looking at, Hey, what fork partner can we bring into the mix?

All of a sudden, a lot of variables came into play in terms of like the rake of the bike or the rank of the fork, like all of these different things. We started having to consider. And what was the effect on tau overlap? What was the effect on like what ties size tire are they designed on accommodating?

So is it really like, I don't know, a sink of like a week to figure out a, what do we want? And B who actually manufacturers a fork that has those correct dementia.

[00:21:29] Randall: And that we can get in a reasonable timeframe.

[00:21:31] Craig: yeah. And then to, to further that, you know, everybody knows I'm suspension curious, I've got one bike in the garage right now with the front suspension fork on it, from my friends at RockShox.

And I do imagine playing around with that, on this bike, but as we've spoken about previously, probably in an, in the dirt episode, and certainly when I dug into it with our friends at rock shock and Schramm, you know, if you put one of these suspension forks on the bike, it's going to bring the entire bike up because that 30 to 40 millimeters of travel has got to come from somewhere.

So we had to think through, okay, if we have a 3 95 axle, the crown length of the rigid. What happens when that's four 20.

[00:22:14] Randall: Yeah. Or 4 25 in the case of the RockShox fork. And then they have two different offsets. And what we came to is, well, You know, that 30 millimeter of difference means that your front end is going to come up. Right. And so to get the same exact position, you'd have to, you know, shift your saddle forward and you would have to, you know, adjust your stem height and so on.

Or you could just make it so that you know, your, your position. In with the rigid fork is a little bit more aggressive. And then you're just, you know, allowing that, that slightly more you know, lean back position, slightly more upright position when you have the fork and in terms of the handling characteristics and so on, they actually change the position.

Characteristics change in a way that is appropriate for a bike, with the added capability of a short travel suspension fork. And so it's, it's kind of, you know, not really a problem. And we ha we don't have a, an adjustable suspension, sorry. We don't have an adjustable geometry with that rigid fork, which is something I'm a big fan of, but we're getting adjustable geo with the swapping of the forks in your case.

And we designed accordingly.

[00:23:20] Craig: Yeah, it's super interesting. And going back to my conversation with Chris Mandel from SRE. He said the same thing. Like it was, it was really early on. They had literally just launched that FOC that fork. And I was able to spend some time on it before the launch. And he said, you know, I put this on a bike that wasn't specifically geo corrected, but I felt like it was okay.

He's like I've spent months and months and months on this thing. And it just modified the geometry in a way that made sense for the new way that I was going to be riding the bike with a suspension for.

[00:23:52] Randall: Yeah. And you know, you, it is useful if you're considering adding a suspension fork to your existing bike, to say, throw it, throw it in a tool like bike geo calc. So take your current geometry for your bike and put it into that, that tool and then set the settings so that the frame rotates when you change the axle, the crown and it'll tell you how the other parameters change and that can also inf not only inform you in terms of how.

How the geo would change, but then also how the handling might change, which would help you decide, say what fork offset you want, because you know, RockShox offers two different offsets on those forks.

[00:24:27] Craig: Yep. Yeah. And I'll have plenty of room on the steer tube, as well as the ability to flip my stem, to make adjustments accommodating that, to get the position. Right. And again, just make, make that, that Delta between 3 95 and 4 25. Feel the slider than it actually is.

[00:24:48] Randall: Well, and it's, it's small enough where I do think that it's quite likely that you can get a slightly more aggressive, but still upright position with a rigid fork and then a slightly less aggressive, more upright position with the suspension fork that, you know, feels good in both of those different applications and feels appropriate for those.

So I don't suspect that you're going it's. I don't think it's highly likely that you're going to need to move around much. And this actually gets into a conversation I'm looking forward to having with Lee McCormick at some point when we bring them on the podcast, which is, you know, talking about how, you know, we've talked about stack and reach and how these are really important measurements for determining fit.

But it in turn in as a rider, like the big thing that matters is like the distance from your crank spindle to where your hand. And then you have an, you know, an anchor, so that high pot news between, you know, the, the stack figure to the grips and the reach figure to the grips, the high pot news is actually the, the, the pure number.

And then the angle associated with that that high pot news. But that, that the length of that hypotony is actually shouldn't change from bike to bike. So whether it's a road bike or a mountain biker, so on, it should be consistent. And then it's the angle of that that. From bike to bike. And so if you think about, you know, the front end coming up well, that, that, that distance is staying the same.

It's just the angle. That's increasing a little bit.

[00:26:08] Craig: Right. Yep. Yeah. A hundred percent. You know, I love, I love most of my bikes are set up identically, so that basically, if I have my eyes closed, I know exactly where to fall and hit the bar. And it's so great that my like mountain bike and rode by can feel like that same position.

[00:26:25] Randall: Yeah. Yeah. And even better, if you can get, say the same crank lengths on the bikes, the same, you know, pedal positioning, you know, stance in the, like on the bikes.

[00:26:35] Craig: Yeah. I'm sure I'm a little bit a field from that, but this is the most bike geekery by the way that I've ever gone through. And it's, I mean, part of it's been driving me mad cause I really want to consummate this Ram and say the design's done. And I do think like if, if we're not at the finish line today, we're in the, we're in the final sprint, we've seen the and where we're coming to the finish line.

Thank God. But a couple of other things I wanted to just quiz you on before we get to that point. So there was also the question about BB drop and it was another one that was like BB drop. I've never thought about that. Just allowed the frame of the production frame, builder to think about that. But now that we have to consider it and we could do whatever we wanted, let's talk about the movement on that.

And what's the rationale and just, what's the takeaway for the listener at Ron BB drop.

[00:27:28] Randall: Yeah. So Bebe, you can think of BB drop as you have the, the vertical distance between the height of the axles and the height of the bottom bracket. The center of the bottom bracket spindle. So the bottom bracket spindle is going to be below the two axles, right? And the greater the more below the two axles it is you know, ceteris paribus, the more stable the bike is going to be the more sitting into the bike.

You're going to be.

[00:27:54] Craig: to sort of visualize that if I'm, if I'm sort of the listener and I'm thinking about my bike, I've got my two axles on my wheels. And I'm thinking about how far below that axle line, the bottom bracket sits.

[00:28:06] Randall: Exactly. Exactly. And So, with like old schools, cyclocross geometries, the bottom, the BB drop tended to be pretty high, you know, 65 versus a, you know, your thesis will be one to 73. And your OB one only accommodates up to a 700 by 40 tire, but it's really optimized around 700 by 30 and 60 50 by 47, which is like a 700 by 28.

And so, you know, it's, there's, it's you get more stability, but there's greater risk of pedal strikes as you drop the baby. Now with your new bike, you know, we started with your, your thesis as like a starting point. Cause he really liked that geometry and we saw, well, you're going to be optimizing this bike for running with bigger and thus taller tires, a bigger radius from the center of the, the axle to the outside of the tire.

And so you can you can drop the BB further and get that added stability without increasing risk of pedal strikes. And in fact we also went with a 2.5 millimeters shorter crank. And so you're actually going to have more clearance above the ground with those bigger tires, even though we dropped the BB down to improve stability.

So you know, that that was kind of a very natural thing. And you see this trend in general on this newer slate of gravel bikes that are being optimized for higher volume 700 tires versus the more one bike type bikes like the thesis or the the Sabelo Sparrow. That are designed to be used effectively with road, you know, seven up to 700 by 30, which is, you know, a smaller radius

[00:29:37] Craig: So, does it feel like you're sort of sitting more in the bike when you have more BB drop?

[00:29:42] Randall: exactly. Versus on top of it.

[00:29:44] Craig: Yeah. Yeah. And I, you were saying about cyclocross bikes having a 65 millimeter drop, presumably that's because they're doing a lot of things that require clearance, bunny hopping barriers and things like that.

[00:29:57] Randall: Yeah.

Concerns about, you know, pedal strikes, essentially as they're going over different obstacles though, even those bikes with the advent of gravel, you've seen those bottom brackets come down because there's no reason. I mean, I would argue there's no reason to have a dedicated cyclocross bike, unless you're, I mean, even if you're an elite cyclocross athlete, you can still ride on take this specialized crux as an example, that bike fits six 50 by 40.

Right. So it's not constrained to the 700 by what, 33, that the UCI maxes out cyclocross tires for. So even that bike is, is, is really a gravel bike that, that people are, are using in that discipline. So it doesn't need a dedicated bike anymore. So those are the days of high bottom brackets is have thankfully gone away

[00:30:45] Craig: Yeah, I think that makes sense. Yep. Certainly no reason for the average athlete to own a dedicated cyclocross bike. If you've got a gravel bike in the closet,

[00:30:53] Randall: Yeah. Yeah, for sure.

[00:30:55] Craig: the other thing we had to consider was just cable routing as well. And again, this is like, Maybe on a carbon bike, you make a couple ports and you know how to seal them pretty easily.

And if you use them, you use them. If you don't, you don't. But when you're talking about a metal bike, all of a sudden you you've got okay, either I'm going to externally route everything, which I don't like the look of, and that seems old school, or I'm going to actually have to drill and sort of weld holes into various parts of the frame.

And that was again, Another consideration. Well, what, what am I going to do? Am I going to commit to wireless? Which is like a very viable option these days? Or am I going to get, you know, have four different ports drilled into this frame? And I opted to go the wireless route.

[00:31:44] Randall: Yeah. And I think that that was a smart way to go. The, you know, especially if you're already going the, you already kind of, unless you're going to do external cabling, internal cabling on say like a steel or titanium bike. Is going to be such that, like, you're going to have some sharp angles going through the frame, especially, you know, where that down tube is meeting the bottom bracket shell, you know, you don't have these big, these big tubes and these big open spaces, like you can mold into a carbon frame.

And so there's going to be sharp angles. There's going to be sharp surfaces that need to be machined. It's just harder to do. It's really hard to do good, clean mechanical routing internally through a metal frame, unless it's say something like a specialized, smart weld aluminum frame where they're hydro-forming those, those tubes to get a more carbon shape.

[00:32:35] Craig: Yep. Yeah. Yeah. And when you consider adding in, which was a necessity for me, a dropper post yet another whole, yet more routing. So yeah, I'm committing to going full wireless, including the dropper. On this bike. So I'll, I'll just have the rear brake cable routed through the frame and that's it.

[00:32:54] Randall: Yeah.

I think too, that's going to, I mean, given that this is your adventure bike it's just that much less to deal with as well when you're taking the bike apart to throw in your case to bring on a plane. So I think that wireless can make sense. Just bring an extra battery.

[00:33:09] Craig: Yeah, a hundred percent. My my contact at SRAM, I went riding with him on Tam gosh, probably four or five months ago at this point. And his battery ran out, but he keeps a spare in his seat bag.

[00:33:23] Randall: Yeah. And if you're going with a one by set up too, like you have those two coin cells, which are very lightweight and the leavers. So if one of them dies, he still got the other one. You could swap it over.

[00:33:32] Craig: Yeah. Yeah. The cool thing about their RockShox C posts is that you can steal the battery pack from there and use it in your derailer if you need to, because they're all, they're all changeable not to, not to have

[00:33:44] Randall: they have to make, well, then you have to make the difficult decision of like, do I care about gearing or the dropper post more? I guess it depends on the terrain. There are some cases where I would, I would sacrifice the derail, your battery to keep the dropper post going.

[00:33:57] Craig: Yeah.

who knows if I was at the top of Tam, you know, if I was riding up, switch the battery to have gears on the way up and then switch it to the dropper on the way to.

[00:34:06] Randall: Yeah.

[00:34:09] Craig: I love it. You just made me think about, I literally just packed my thesis in my post carry bag for an air flight tomorrow. And there's always a little bit of Jenga with the cables to kind of move everything around and get it in their bag. So well-designed and fortunately with my these medium thesis, I can just slam the seat.

I don't even have to take the seed out and get it all in that bag. Hopefully continue to allude all airline fee.

[00:34:36] Randall: Excellent. I'm

[00:34:38] Craig: you for walking me. Yeah, no, I think we've covered a good deal about the frame between this episode and the last episode. And again, I hope this conversation gives you a little bit of inside baseball about how frames are designed. If. Looking to get accustomed frame done. It's important to have a builder who's willing to work with you.

And in my case, just being someone who's just not in the weeds on all these minute dimensions and angles, just someone who's patient and will walk you through what needs to be done. I'm lucky to have both the builder and Randall to help me out.

[00:35:13] Randall: Yeah, it's it definitely you know, the value of working with a good bow builder in, in significant part comes on the front end and really trying to dial exactly what you want and, And you know, having that output down the other end. So.

[00:35:28] Craig: as I, as I think about your journey with thesis and the idea of designing, was it five frame sizes?

[00:35:35] Randall: Well, so in our case, we went with we went with an open, we went with an open mold frame and then made modifications from there. So we use the existing tooling. So we were fortunate to be able to find a frame with, you know, the vast majority of the features we wanted and the exact geometry we wanted.

And then we added the features and reinforcements from there. So with the next gen frame beginning development of this is this is a ways out that'll be a full ground up exercise.

[00:36:03] Craig: Yeah.

it's just, I imagine it's so challenging to sort of figure out the sizes. Obviously you're matching what the market trends are in terms of how the bikes are performing and what they're intended for, but just like the basics around stack and reach to try to find those sweet spots, to make sure with the limited amount of customability customizability, I E you know, you're stem lab.

The your stack above the head tube making that fit as many people as possible. It's just seems to be a challenge.

[00:36:35] Randall: Yeah,

And it's, it's even more so with a material like carbon where you're, you know, essentially you're, you're creating these molds that are quite expensive. And then that's set in stone. If you want to evolve your metal, a tube to tube constructed frames, geometry over time. You know that that's it.

You just change the jig and you change the mitering specifications and you're good to go. Carbon it's a whole new tool, so you better get it right out the gate.

[00:37:01] Craig: so true. Well, thanks for all the time, my friend, this coming weekend, hopefully I know I'll be seeing you and hopefully we'll be seeing a bunch of listeners over there at at

[00:37:11] Randall: sea Otter three o'clock on Saturday at

the scratch labs booth.

[00:37:15] Craig: Yeah, we'll see you there.

[00:37:17] Randall: All right. Hope to see some folks there.

[00:37:19] Craig Dalton: That's going to do it for this week's edition of in the dirt, from the gravel ride podcast. Thank you for spending a little bit of your week with us. If you're going to be at CR definitely come find us at the scratch labs booth at 3:00 PM on Saturday. Huge. Thanks to thera body for sponsoring this episode, please visit thera body.com/the gravel ride for that special offer around the recovery air.Jet boots.

If you have any feedback for Randall or myself, feel free to visit us at the ridership. That's www.theridership.com. And if you're interested in supporting the podcast, please head over to buy me a coffee.com/the gravel ride. Until next time here's to finding some dirt onto your wheels