jimmymcg

After searching the web for an age I can't really find any real answers.
Most reviews tend to focus on gravel riding and may even say they feel great on road. Other sites talk about the rolling resistance which leads to the skinnier 700c tires always coming out better but these neglect road surface.
I was wondering if anyone here went from 700c to 650b and ride prominently on the road. Do the wider tires slow you down much on rough roads?
Most roads where I'm from (ireland) are pretty rough asphalt.
I'm looking to buy a new bike that I can ride long distances in comfort. Rides like the transatlantic and eventually the trans continental.
Any help with this would be great.
Thanks
James

unterhausen

it really depends on the tire. A bigger tire that is made to be robust is probably going to be slower. Rolling resistance wise, the conventional wisdom that smaller tires have less is not true in general

jimmymcg

Thanks guys. I appreciate your feedback.
I think it worth a try. Worst case scenario I can swap the wheels from my current bike.

u235

My normal tire is a 40c and I've used 45c Riddlers on mixed centuries with at least 50 miles of road. I'm solo and not racing myself so it depends on what you are used to I guess. Anything adding weight or drag will have an impact. It's up to you to find the balance.

unterhausen

I rode this year's 600k on 700c 40mm Maxxis Velocita run tubeless. They do seem to be a bit more work to accelerate than smaller tires, but roll really well once you get going. It came in handy, who would have thought New Jersey roads were so horrible? I also rode that same bike on the 600k I dnf'd, that route goes on gravel bike trails for many miles, and I think I would have had trouble on my usual 32mm tires.

I'll probably set my disc rando up with 40mm tires. I can always go narrower if I want

ThermionicScott 

One of my few lucid thoughts as I pulled into the finish of PBP 2015 was that I would have been plenty comfortable on 32-35mm tires, as opposed to 38mm. And that Panaracer Col de la Vie's were not the best choice on top of that. Don't get those! (See also: BQ Vol 5, Num 1)

I'm convinced that there are two primary reasons why 650B died out the first time: 1) French roads improved in the 1950s, so those riding on roads simply didn't need such large tires anymore, and 2) wide tires need to be lightweight and dare I say it -- supple -- in order to keep from being slow. If you weren't on "boutique" tires, you not only felt slower, you likely were, compared to the tubulars and half-decent 700C clinchers of the day. 650B survived a bit longer in heavy-duty utility/city tire form for the same reasons 26"x1-3/8" lasted so long in England, it does the job fine as long as you're not trying to ride fast.

But 700x28C is not cushy enough for a lot of the roads I ride, so I'm kinda stuck in between. If I had any bikes that could take 700x32C and fenders, but didn't result in toe overlap, that would be ideal.

rando_couche

Similar experience. My road bike (Merckx Team SC) with 25mm handmade Vittorias is 1.5-2 mph faster on average than my Mondia with 650x42c Pari Motos. BUT... they're two very different bikes and I'm one of those whose performance is very much influenced by how a bike feels. No way a 30lb bike (Mondia) is going to feel like a sub-20 lb bike (Merckx).

Oh, and the roads here in Oregon are usually "not very good", so the wider tires get a big "plus" there. I'd LOVE to try and 18 lb bike with 42mm tires, but...

unterhausen

There was some chip seal on the PBP route in 2011 that probably would have been nicer on bigger tires. I was running 25mm back then. I'm pretty sure that section was gone this year, and I was wondering if it was because of the road surface. They took us on much bigger roads there. There was one road this year that would definitely have been nicer on 42mm tires. I run 32mm, and it was too rough on those. But there were no potholes, strangely enough. There were times I thought I would have been happy with the 25mm tires

I have a set of brand new 650b wheels/tires and have never talked myself into using them.

kingston 

I started randonneuring on a bike with 32mm tires, wanted to try out some wider tires so I got a bike with 38mm tires. I still have the first two, but now mostly ride a bike with 25mm tires because they're fast, abundantly available, and perfectly adquate for the conditions I ride. I'm sure there are times when 650bX42mm is a nice setup, but I don't come across those conditions very often on brevets. As @ThermionicScott suggests, if you want to run wide tires and not give up a lot of speed, RH is pretty much the only game in town, so get out your checkbook.

ThermionicScott 

Panaracer Pari-Motos are a pretty cost-effective way to taste the Kool-Aid, though.

unterhausen

There were a couple of stretches on Mac 'n' Cheese where I really would have liked to have bigger tires. The long stretch of road with expansion joints before the lake control on day 3 being the prime example. I'm pretty sure I got nerve damage from that road. Also, I thought I was going to get pinch flats while riding in downtown Green Bay.

I switched from 25mm tires for good when I got a pinch flat in the dark in the rain just after the start of a 400k. I had already ridden a series on 38mm tires, and not worrying too much about not seeing a pothole was nice. And I don't think they slowed me down much.

Tourist in MSN

My comparison is between 26 inch wheels and 700c, not 650b. I find that they are essentially the same if the tire construction is the same. In other words, I find that a 37mm wide 700c tire that is constructed the same way (same make and model) as a 40mm wide 26 inch tire rolls the same and they are indistinguishable from each other.

But my 700c bikes that have fenders all have toe overlap, my 26 inch wheel bikes do not. I do not know if 650b would have toe overlap or not, would likely depend on the specific bike.

A note on tire pressure, I did some riding in spring 2018 on a week long van supported trip in West Texas on a very rough chip seal for the full week. My bike had 40mm wide tires. The first day my front tire had about 55 to 60 psi in it, the vibration on my hands was really bad, my GPS started acting quite weird with the vibration. The next day I dropped my front tire pressure to between 40 and 45 psi. Since the tires were 40mm wide I was not concerned about pinch flats at that low of a pressure. With that lower pressure my hands did not take the beating that the vibration on the first day caused, my GPS was much happier and quit shutting off too. Since the problem was vibration on the handlebars and not the rest of the bike, I left my rear tire at the original pressure which was in the 75 to 80 psi range for the rest of the week. That said, I think I could have run that wide of a tire on any wheel size and ran that lower pressure, so I do not think the wheel diameter is that critical.

In the mid 80s I could not find replacement 650b tires in USA, thus my 650b bike was retired at that time. Have not ridden a 650b size tire since then.

ironwood

Some riders finished the Paris Brest Paris event on 650B tires with respectable times. I don't know what size tires Fiona Kolbingen had on her bike in the Transcontinental.

StephenH

I've got one set of 700 wheels with 43mm tubeless Panaracers on them for gravel use, and use 28mm tube-tires otherwise. I'd say maybe 1-2 mph difference between the two. We have some rough spots here and there on local brevets, but generally not enough to merit using tires that large. If all the roads were like the worst stretches, it might be different.

joewein

The Canyon Endurace WMN CF SL Disc 8.0 Di2 she rode has enough tire clearance for 30 mm. The factory tire is a Continental Grand Prix 4000s II 28 mm, but I'm not sure what she went with.

bikemig 

There are a lot of older road bikes that can take 32c tires and fenders . . .

And there are a lot of older high end touring bikes that can as well.

bikemig 

I ride a 1993 Bridgestone XO 2 a lot on rough roads and longer rides. It has road geometry but it is build around 26 inch wheels. I run Panaracer Pasela PT 26 x 1.75 tires on. Good tires. I ride the bike on bad roads and long rides because those tires are comfortable and you don't have to worry much about the road surface.

rhm

Most of my long distance riding is now on tires 40mm or wider, running at relatively low pressure. I've done 600, 1000, and 1200 km rides on 53 mm tires.

Whether they really are as fast as other tires, I just don't know. They are comfortable and I rarely get flat tires, so I have no complains, but the move to fatter tires has not changed my life. One thing I do like, about fat tires, is that I don't have to be picky about road quality. I can roll over a lot of rough stuff. I still prefer smooth roads, though.

kingston 

I rode a 600k over the weekend with a guy on a soma with RH 650bX42 tires, and I was on my seven with 700X25. We were pretty well matched on most of the ride. He was a bit faster than me on rough pavement and the few gravel sections. I was quite a bit faster than him on the hills because my bike was 10 pounds lighter. One of those BQ style custom 650b's with lightweight tubing is probably the best of both. A woman in our club finished on a fat-bike proving once again that pretty much any bike will do.

unterhausen

I have noticed it's more work keeping up with someone on 42mm tires on rough chip seal. I would have thought 32mm was wide enough for that. That experience was why I rode my gravel bike on the 600k that featured rail trail

Tourist in MSN

If you mean the 200k on August 3, I admit that I found it rather embarrassing that she finished faster than me when I was on my 32mm tires.

And, then I learned she had problems with a new shifter and that she often rode in a gear that she did not want to ride in. And she was still faster than me.

But as long as neither of us did not DNF, that is all that really mattered.

kingston 

She finished the 600k last weekend.

Tourist in MSN

That is VERY impressive.

pinholecam

Comparing my TT bike (700c 23mm tires), a few 451 mini velos on 28mm and my newly setup gravel bike (650b 42mm Pari motos), the 650b with 42mm feels very different.
I ride mostly with/vs roadies for the local rides here and the gravel setup is really for overseas bike touring, but I like to see if I can get away with.

Pros
----
1. I can largely ignore most road irregularities.
2. If there are climbs or descents that also have bad road surfaces, the 42mm tires are better

Cons
------
1. Climbing vs lighter roadbikes (or my own TT bike) on good roads is certainly slower and requires more effort.
2. Speed drops by about 3-4kph
3. Certainly more effort needed to get to speed (and keep it)
4. Slower acceleration


Other notes
-------------
1. Though I have been able to keep up or even get ahead of other riders on road bikes, I know that it takes more effort to do so and becomes hard over a longer ride.
2. Speed is not a real problem riding alone with a loaded bike (so maybe comfort takes over as a priority? )
3. 42mm does not seem to be the right width for road riding unless one rides in beaten up roads most of the time.
4. I'll try 28mm tires soon to see how the weight/speed/comfort equation works out.

joewein

I went from 30 mm wide 451 (20" x 1 3/8") on my Bike Friday to 650B x 42 mm. Going from 65 psi on the narrower tires to 42 psi on the wider ones was a pretty significant gain in ride comfort.

In the first year I didn't actually see much evidence of a difference in speed so I concluded it was about the engine after all. I did feel fresher when I arrived at the brevet goal though. In the next two seasons my brevet times improved significantly though I'm not getting any younger and had actually put on weight.If anything, that big front bag for the porteur rack encourages also me to bring more stuff.

I feel much safer on the wider tires. Ultimately, maintaining my "Century a Month" status (at 85+ months now) is all about avoiding injury. Gravel that would have worried me on the narrower tires I don't even think about and awful roads that would have been scary before I will still ride with confidence.

On the narrower tires I used to think 2,000 km (about 3 months) between punctures was pretty good. On the BSP and BSP EL I've averaged 14 months and counting so far (3x in 43+ months). My longest puncture free stretch on the BSP lasted for 22 months.

I'm sold on 650B. Given that the vast majority of my riding is on roads I probably wouldn't benefit much from going from 42 mm to 54 mm. I don't know how much comfort I'd give up if I went to 38 mm, but given that my Elephant NFE has enough clearance for 42 mm with fenders, there's no real reason for going for anything more narrow but with slightly higher pressure.