Sam/Roadini Comparisons with wheel size difference

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dane...@gmail.com

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Dec 7, 2024, 9:32:09 PM12/7/24
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Hey

So I've been enjoying my Roadini and taking it on everything from paved roads/dirt roads to some chunky stuff.  I'm 5 foot 7 with short legs, 670 ish saddle height with 155 cranks.
The Roadini is a size 50 which has a 55 ETT.  I'm running a 70mm stem with short reach drops.  I'm a little on the edge of sizing with the bike.  Also, every time I throw the 32mm tires back on after riding 44s for a while,  I prefer the handling and am thinking about a switch to a similar 650b bike so I can get the sameish wheel diameter size with a 42/48 to maintain that feeling with a wider tire.  I've had a few 650b bikes but they were all low trail, which I decided I don't really like after all.  The 48cm Sam is 650b and I'm wondering if I'll be giving up any of the more road-ish feel of the bike with the same build but in 650b form on the Sam?  Seems the Sam would be a little more versatile and have better braking options, but a degree slacker STA and the HTA down to 71 from 72 on he 650b Homer.   Wheelbase is about 10mm longer on the Homer.   Anybody have any experience here?  The other possibility for me is possibly getting a custom bike made, but we're talking double the price so I'm curious if maybe I could make the Sam work.  

Thanks
-Dan

Jason Fuller

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Dec 7, 2024, 11:24:56 PM12/7/24
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Knowing what your routes are like Dan, I think the Hillborne would be killer!  I've never ridden a Roadini but having also come from a few low trail 650b rando bike before getting the Hillborne, I don't feel like it's objectively slower feeling. I hugely prefer the feel of 650 over 700 once the tires are 38mm and up too, i'm a little taller but not much. Less toe overlap is nice. 

Ted Durant

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Dec 8, 2024, 7:48:07 PM12/8/24
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On Saturday, December 7, 2024 at 8:32:09 PM UTC-6 dane...@gmail.com wrote:
The 48cm Sam is 650b and I'm wondering if I'll be giving up any of the more road-ish feel of the bike with the same build but in 650b form on the Sam?  Seems the Sam would be a little more versatile and have better braking options, but a degree slacker STA and the HTA down to 71 from 72 on he 650b Homer.   Wheelbase is about 10mm longer on the Homer.   Anybody have any experience here? 

I don't have a Roadini, but I have a Heron Road and Rivendell Road, which are pretty similar, and I have 3 Sam Hillbornes. I bought one Sam, not sure what I would think of it, and ended up buying 2 more, with 2 of them living at my daughters' homes. I've posted a few times about this, so for those who've heard it before, feel free to skip this one!

The Sam is the heaviest bike I have at this point, and I _love_ riding it, and I don't think it slows me down in any significant way. I ride ~48mm tires on all three of them, maximizing the all-road utility, which I have used to great advantage on dirt mountain roads around LA, gravel roads in Maine, and lots of bumpy tarmac in Wisconsin and Ireland. The handling is certainly different from my road bikes, but I have never thought "gee, I wish I was on one of my other bikes" while riding a Sam.  I haven't tried, say, 38mm tires on a Sam, but I expect they would significantly sharpen the handling (along with lowering the COG by 10mm). 

Don't underestimate the impact of the 71.5 degree seat tube angle, which compares to 73 on my Heron and Riv (and 73.5 on my Waterford ST). It puts the saddle 18mm farther back than a 73, at my saddle height of 715, without making any offsetting changes to the saddle position in the seat post. You have to take that into account when calculating what length stem to use. I've noticed some hand issues, especially on my Waterford, and I'm realizing now that the steep seat tube angle is probably a contributing factor.  Whether a slacker STA is good for you, only you can decide. I would note that, in general, the faster you ride the steeper a STA you'll tolerate, because you're putting more weight on the pedal, which unloads your hands. My hand issues on my Waterford are particularly noticeable if I'm loafing along. I can loaf more comfortably on the Sam, without any apparent loss of ability to put my (limited) power to the pedals.

Interestingly, I was recently measured by a bike builder and his design for me uses a 71.5 STA.

Ted Durant
Milwaukee WI USA

Spencer Robinson

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Dec 9, 2024, 9:53:28 AM12/9/24
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This topic is interesting to me. I have had my side pull brake Sam for a good decade or so, I have it setup with 38’s, fenders and this past couple years I am back on Albatross bars. I also have a Heron Road with drops and 32’s. I know that a lot is subjective but the Heron feels much lighter, faster. The Sam feels sluggish as compared to the Heron. The drawback to the Heron is that 32’s are just about the largest tire you can fit, I feel like for where I ride, if I could fit 38 or even 42, the Heron would be perfect… Long story short, it has led me to look at the Roadini, but I keep coming back to the thought that it doesn’t seem too much different than my Sam and is there enough difference to make a difference. I would consider the Roadini as my all road bike and set the Sam up sans fenders with larger more off road tires. The Heron would be my go fast with the roadies bike.

Damien

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Dec 9, 2024, 11:07:49 AM12/9/24
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I've actually had both - a Sam 51 and a Roadini 50. I can share my very personal experiences. Both were great in different capacities. On my Sam, I rode with both 48mm and 43mm tires. The 43mm tires I thought were the sweet spot for that  bike (for me). Not to say I didn't like the handling with 48mm, but that it was a much different, more tank-y feel. It was great! On the Roadini, I had 700x33mm tires, and that bike felt much nimbler and road-ish than the Sam with 48s. However, the Sam with 43s felt much closer to the 700x33 set up on the Roadini, although there was still a difference with the 700s feeling consistently more sprightly. I can't speak to 700x44 vs 650bx48, although if I were to hazard a guess the 650bx48 would feel better. Also to keep in mind:
  • Roadini was built with lighter more road-ish components and wheels. I don't believe the impact of those can be ignored in my comparison
  • On the other hand, the Sam was built with more "typical" Rivendell stuff (i.e., Sugino triple, Velocity/Deore wheels, both Albas and wide Nitto Noodles). Weight was not a consideration in this build which again, has an impact on feel (thought not in any negative way - just something to keep in mind).
Sam was more versatile especially when it came to rackability/hauling, but honestly I think the Roadini is also versatile - just maybe more towards the road/light trail side of the spectrum, where the Sam can get beaten up a little more if you're on the chunk. I think both options could work depending on your preference.

So in short, buy a Sam and also keep your Roadini!

Damien

p.s. For what it's worth, I've sold both and now have a Hunq for trails/hauling/child-carrying and a Roadeo. Less overlap than what I had with the Roadini/Sam set up as both bikes are a bit more specific in nature....but both are still versatile and awesome, and you will almost always have that with Rivs.

Ted Durant

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Dec 9, 2024, 11:40:05 AM12/9/24
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On Dec 9, 2024, at 8:53 AM, Spencer Robinson <gogou...@gmail.com> wrote:

 The drawback to the Heron is that 32’s are just about the largest tire you can fit


My, how far we have come since 1997. When Herons were designed, cyclists on 28mm tires were obviously Freds. If you wanted 32’s, you searched out Campionato del Mondo sewups. It was a battle to get builders to set brake bridges and fork length to maximize the 57mm reach of “long” brakes. The pads on the brakes on my prototype Heron are smack dab in the middle of the slots. I have 32mm tires crammed in there. I also have 32’s crammed into the Campy Daytona brakes on my same-era Riv Road. If Grant Petersen and Jan Heine are remembered for nothing else, I hope they are remembered for how much joy they have brought (back) to the cycling world with an embarrassment of riches in choices of large volume tires and bikes and components that take advantage of them. 

Ted Durant
Milwaukee, WI USA

dane...@gmail.com

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Dec 9, 2024, 11:51:16 AM12/9/24
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I do generally prefer a slacker seat tube angle.  I ride 155 cranks and even though when your saddle goes up to accommodate for the cranks it generally needs to go back a bit more still.  The Roadini has a 72.5 STA and my Berthoud saddle is more back than forward right now.   

Weight could be interesting because with the same build, smaller frame and 650b I could see the Sam actually being lighter.

-Dan

Piaw Na

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Dec 10, 2024, 12:56:00 PM12/10/24
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My, how far we have come since 1997. When Herons were designed, cyclists on 28mm tires were obviously Freds. If you wanted 32’s, you searched out Campionato del Mondo sewups. It was a battle to get builders to set brake bridges and fork length to maximize the 57mm reach of “long” brakes. The pads on the brakes on my prototype Heron are smack dab in the middle of the slots.

Ironically I had the opposite problem. When I spec'd my custom Ti touring bike I asked for 57mm because that's what the spec said. It turned out that if you have exactly 57mm just because of the vagaries of the process you end up having to file down the brake slots of the "long" reach brakes. To be safe you really have to design/build the bike to 55mm reach.

It is very amusing that I went from having the widest tire in my touring club (25mm on single, 28mm on tandem) to having the narrowest tires in my touring club (28mm on single, 32mm on tandem) over 15 years.  On reflection I think what people don't understand is that rider/bike weight matters a lot. At 120 pounds and riding a 20 pound bike my wife riding 32mm tires is like a 180 pound guy riding a 30 pound bike using 40mm tires. My kid at 95 pounds riding a 24 pound bike can run 45psi tires on 28mm tires and easily rides single track with no traction difficulties. I get people giving me a hard time for "downgrading" from 32mm tires to 28mm tires, not realizing that at 160 pounds total bike weight those 28mm tires are equivalent to their 35mm tires.

Ted Durant

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Dec 10, 2024, 1:24:01 PM12/10/24
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On Dec 10, 2024, at 11:56 AM, Piaw Na <pi...@gmail.com> wrote:

Ironically I had the opposite problem. When I spec'd my custom Ti touring bike I asked for 57mm because that's what the spec said. It turned out that if you have exactly 57mm just because of the vagaries of the process you end up having to file down the brake slots of the "long" reach brakes. To be safe you really have to design/build the bike to 55mm reach.


This is a geometry problem that affects the front much more than the rear. The seat stays, to which the brake is attached, are almost exactly perpendicular to the brake track where it crosses between them (depending on the rear axle location relative to the seat stays, and whether the seat stays are straight). The brake mounting hole, being perpendicular to the seat stays, is parallel to the brake track. But the rim is running away from the brake hole as you get farther from the bridge, so if the hole-rim distance at the bridge is 57, then, yeah, because the brake sticks out from the bridge, at the center of the brake pads the distance will be >57. 

The front brake is a different story and more problematic, typically. Front brake holes run perpendicular to the steering axis, but the brake track is pretty far from perpendicular to the brake track. By the time you get to the center of the brake pads, the brake track has moved significantly upward, so if you are at 57 at the fork crown, you might have 50 or less at the center of the pads. Which screws you when you try to install fenders.

I have yet to encounter a builder who explicitly does the math to figure this out. I’ve suggested to a couple of builders they drill front brake holes at an angle to preserve brake clearance … they’ve politely dismissed me as a crank.

Piaw Na(藍俊彪)

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Dec 10, 2024, 1:31:34 PM12/10/24
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I have yet to encounter a builder who explicitly does the math to figure this out. I’ve suggested to a couple of builders they drill front brake holes at an angle to preserve brake clearance … they’ve politely dismissed me as a crank.

I no longer ask builders to do math. What I do is to ship the brakes to them and tell them to build the bike around the brake so that the pads are at the bottom of the slots. For better or worse, bikes are built around the brakes you've chosen, and maximizing tire clearance is a key piece.  With the Tektro 559s at least there's so much reach that it's no big deal.

Ted Durant

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Dec 10, 2024, 1:39:17 PM12/10/24
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On Dec 10, 2024, at 12:31 PM, Piaw Na(藍俊彪) <pi...@gmail.com> wrote:

What I do is to ship the brakes to them and tell them to build the bike around the brake so that the pads are at the bottom of the slots. For better or worse, bikes are built around the brakes you've chosen, and maximizing tire clearance is a key piece.

Good advice!
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