650b vs 700c for one bike to rule all roads?

[Toddykins]

I find its more fun each time I go bigger. I only have a couple of days on 650b x 48mm, but I am pretty sold.

[guido]

Well.........they make 700c up to 3.0" and bigger, yeah?


How Gnar-gnar we talking?

- Garro.

I'm not suggesting a maintain bike. The thread is about an ALL Road bike. I'm guessing the bike in the pic would not be a reasonable choice for >100k...

When 700c tires get over 38 they start to feel sluggish and dead to me. Same as 650b x 48. But the 26" x 52 keeps the light fast handling and the flotation...

[dogrange]

I find its more fun each time I go bigger. I only have a couple of days on 650b x 48mm, but I am pretty sold.

I agree, in my limited experience. Now tempted to try 26X54

[guido]

I agree, in my limited experience. Now tempted to try 26X54

Pity you aren't in this neighborhood, I'd be happy to let you try mine...

[steve garro]

When 700c tires get over 38 they start to feel sluggish and dead to me. .

That's what happens to be on there


- Garro.

[jscottyk]

The design criteria for FF509 was 700 size wheel with ~30mm tires (up to ~34mm) and 650B with ~42 (up to ~46mm), 425mm chainstays and spacing for using road cranks.

I had used my cross bike on the road with 35 and 38mm tires. While that tire felt fine in the dirt, on the road it felt lumbering and sluggish in the handling department. I had heard good things about 650Bx42 and how the same trail could be accomplished as a 700x30.

In the end, that’s been my experience. 700x30 and 650Bx42 feel the same WRT to handling. In 700 my wheels are pretty much always fitted with Schwalbe Pro One in 28mm; they measure 30 on the NOX Citico rims. In 650B, I change up the tires more often; different treads for different purposes. Currently, I’m rolling the latest Compass Babyshoe Pass in 42mm. I love this config.

[RanOverMyTongue]

As an experiment I tried 650b x 42 last year. They felt slower than 700 x 32 but my computer told me otherwise. After the tires broke in they seemed faster. I’ve tested them on pavement, gravel, packed road base, and snow, and they’ve been awesome. I keep thinking I need to put the 700s back on, but haven’t gotten around to it. Now I think it’ll be less effort to sell them.

Basically I’m looking at them similarly to my skis. Once there was a time when my short skis were 208s, and the turn radius was measured in parsecs. Not really using those much anymore either.

[thollandpe]

And here's a question on bike design.

I can run my 700 x 35's way down in pressure, less than 40 psi and it's hunky dory for rolling resistance and pitch flats. But the bike steers like a truck on pavement and I want 50 psi or more just for the feel.

Is that a geometry thing?

And Garro, I'm totally on board with your big bike = 700c idea, but I think if Capt. Bill's tailor measured a 34" inseam he's well short of the mark.

[RanOverMyTongue]

Total guess here, but it might be a tire thing. I had Pacenti Pari Moto 42s that we’re happy at 60psi, and now Panaracer Gravel King 42s that like 40psi. My wife has very kindly pointed out that I have not lost any weight between these tire sets (although I am clearly maintaining my spare). Both tire models nare made by Panaracer and have identical file treads. The websites are not super clear, but the tires seem to have very similar assemblies. I don’t know why they are happy at different pressures. This may be related to what you are experiencing, so if you have other tires, you might be able to experiment.

[jscottyk]

And here's a question on bike design.

I can run my 700 x 35's way down in pressure, less than 40 psi and it's hunky dory for rolling resistance and pitch flats. But the bike steers like a truck on pavement and I want 50 psi or more just for the feel.

Is that a geometry thing?

And Garro, I'm totally on board with your big bike = 700c idea, but I think if Capt. Bill's tailor measured a 34" inseam he's well short of the mark.

In my experience, yes. My current setup is Compass Babyshoe Pass in 650B x 42mm. Pressures are 40psi front, 42psi rear. Handling wise, it feels the same to me as 700 x 28mm Pro One (which measure 30mm) at 60psi front, and 65'ish psi rear.

The 650B feels more plush and WAY more comfortable on gravel, slightly more rolling resistance on road (but not terrible), but the bike pretty much handles the same.

[j44ke]

This is a helpful thread.

[steve garro]

And Garro, I'm totally on board with your big bike = 700c idea, but I think if Capt. Bill's tailor measured a 34" inseam he's well short of the mark.

I can read a tape measure just fine, thanks.


- Garro.

[thollandpe]

Attachment 106442

700c

- Garro.

I can read a tape measure just fine, thanks.

- Garro.

34" saddle height or 34" inseam?

[steve garro]

34" inseam?

Yep.

Floor to machinist's square held square held at crotch level (actual standover) against a solid door with feet at shoulder width and preferred cycling shoes on, measured 2x and averaged.


- Garro.

[Two]

I have a few different bikes that fit all the above, and wheel sets that can swap around.

I like my 700c for certain applications, but I stop at about 28mm because the 30+mm tires don't feel right, for whatever reason. Nothing rolls faster than my 23mm 700c on aero wheels on paved roads. They do get a little squirrelly on sand and loose gravel.

Rotational inertia or geometry? not sure, just don't like them. On 650b I like the 42mm offerings from compass the most, and the 38mm for the bike that won't fit the 42mm. The 42mm Babyshoes and Pumpkin ridge are my "go to" tire for almost all roads. If I had to build a bike around one set of tires for all roads, this would be it just because they offer so much versatility. Pumpkin ridge on slushy/icey/muddy roads and Babyshoes for sandy/loose gravel/pavement. I am tempted to install spikes on a set of pumpkin ridge for next winter (most of the ice is gone now unless I head into the Alps to find it). I tried the 48mm Compass tires, but they felt slow.

I have the Rat Trap pass on my titanium-framed, pinion, belt bike. I'm not so much of a fan of them, the additional size doesn't buy me much extra float, and the lack of an actual tread means it isn't that good when things get soupy. There are fewer good 559 options these days for rims. They are plush tires and smooth out light washboard and other things nicely, but they are sensitive to pressure between plush and too much bob with my ultra smooth pedal stroke. They also don't fender as well as the Babyshoes and seem to drop by my BB more than I anticipated compared to the 650/42mm tires -- I'd go with less BB drop if these were my target tires -- I keep scraping pedals on undulating terrain. For reference I have 70mm BB Drop and 172.5mm cranks.

If you go disc brakes, it is pretty easy to take all three without too much compromise.

[Too Tall]

Keep it up this thread might land in the wiki.

[TTX1]

In my experience, yes. My current setup is Compass Babyshoe Pass in 650B x 42mm. Pressures are 40psi front, 42psi rear. Handling wise, it feels the same to me as 700 x 28mm Pro One (which measure 30mm) at 60psi front, and 65'ish psi rear.

The 650B feels more plush and WAY more comfortable on gravel, slightly more rolling resistance on road (but not terrible), but the bike pretty much handles the same.

This is consistent with my experience - rotating various 700x30-33 tires with 650Bx42 Compass Babyshoes.

I go to 45psi rear / 42 front with the Babyshoes, to support my ponderous bulk...

[j44ke]

This would be a perfect split for my (future) set up. (Up to) 700x28 on my road bike and 650x42 on the gravel bike. I am getting more excited about this 650b bike every day.

[NYCfixie]

quoting myself from another thread:

By using total circumference on the chart (and doing some simple math to get the 650b/42mm and 650b/47.5 numbers) ....these best match up:

650b/42mm (2092.30) and 700c/23mm (2098.58)
650b/45mm (2117.43) and 700c/25mm (2111.15)
650b/47.5mm (2133.14) and 700c/28mm (2130.00)
650b/50mm (2148.85) and 700c/32mm (2155.13)


But again, every tire manufacturer measures differently so nobody really knows. Maybe we can only hope to make good guesses.

[Too Tall]

Kicking the back to life because I'm emboldened by the recent Philly Bike Expo. There, thank dog, I barely saw the words "gravel bike". Instead bikes are made to various dims. to allow wheels and tires customers prefer. Road bikes!!!!

Sigh.

I've been testing some Riddler (light) 37s and 40 in 700c on my disk Zanconato. Prior to this the Compass Bon Jons which do everything short of mtn,. biking.