650b: hype?

[Bendo]

Interesting. The Kumo forks have less rake than a conventional rando fork, more like a standard road fork, so I was concerned they would have toe-overlap. I have a bike with a similarly raked fork (57cm frame) and it definitely does have overlap. But thinking about it now, it has 27" (ISO630) rims, so there we might have yet another reason to go 650b! Less chance of overlap that bigger wheel sizes maybe?

Most guys on group rides wouldn't even know what they were looking at. The narrow-minded !! BAN ME NOW FOR SWEARING !! I've encountered from most roadies about my bikes (vintage steel, non-700c wheels, mudguards) means I just can't bothered anymore. Not surprised you kept up with them and great retort too! b

[robHflyte]

certainly different riding in group rides, a bit too much high heart rate and chest beating for me really, I usually ride along a few weeks before a big ride as forced speed training.
But I am thinking of organising an Audax no drop ride soon, one to get Latestarter over his first 300 and also as a way of getting those that may be a little apprehensive of riding 100 or more feeling confident that they can do it. Average moving speed will be in the low 20s, very similar to a BUAF I think.
My Kumo frame is 61cm, I should go measure the rake, it certainly works well with heavily loaded and unloaded front bag so whatever it is, it is fine.

[Thoglette]

g But thinking about it now, it has 27" (ISO630) rims, so there we might have yet another reason to go 650b! Less chance of overlap that bigger wheel sizes maybe?

630 + 2 x 32mm = 694 (almost 700C). To match that you need 55mm tyres on your 650b (Iso 584).

The challenge is brakes - you need 23mm more reach in the same frame/forks

[Bendo]

g But thinking about it now, it has 27" (ISO630) rims, so there we might have yet another reason to go 650b! Less chance of overlap that bigger wheel sizes maybe?

630 + 2 x 32mm = 694 (almost 700C). To match that you need 55mm tyres on your 650b (Iso 584).

The challenge is brakes - you need 23mm more reach in the same frame/forks

Sorry I meant on separate bikes designed for their respective wheel sizes, not just putting smaller wheels in a bigger frame. b

[Virgil Walker]

Just a follow up:
Haven't used 650b. Have used Compass Bon Jon Pass 35 mm Extralight and Stampede Pass 32 mm Extralight (both are 700c) for some time now on road, gravel, and Audax. Best tyres I've used. I prefer the BJPs: I've done my fastest 200s on them, they're excellent on gravel and in wet. Long lasting and only get punctures after about 4-5000 km IME. I get around 7000 km out of the SP XLs. They're expensive, but better than anything else I've used.

[robHflyte]

I find I get increased punctures above 60psi. I've had the Barlow Pass on my bike for over 10,000km and I'm finding more punctures now only because I now ride in an area with a a lot of heavy trucks, pulling out tiny wires constantly. I'm now riding on grass and dirt away from the road to reduce the risk of punctures. But I think I should get a new set, they are getting a bit thin.

Just a follow up:
Haven't used 650b. Have used Compass Bon Jon Pass 35 mm Extralight and Stampede Pass 32 mm Extralight (both are 700c) for some time now on road, gravel, and Audax. Best tyres I've used. I prefer the BJPs: I've done my fastest 200s on them, they're excellent on gravel and in wet. Long lasting and only get punctures after about 4-5000 km IME. I get around 7000 km out of the SP XLs. They're expensive, but better than anything else I've used.

[darkelf921]

The 650b tyres on the Cannondale Slate are good. Finding replacement tyres is close to impossible. When I first bought the Slate, I couldn't source replacement tyres and the tyres which come it hit get shredded very easily.

[owly]

Just a follow up:
Haven't used 650b. Have used Compass Bon Jon Pass 35 mm Extralight and Stampede Pass 32 mm Extralight (both are 700c) for some time now on road, gravel, and Audax. Best tyres I've used. I prefer the BJPs: I've done my fastest 200s on them, they're excellent on gravel and in wet. Long lasting and only get punctures after about 4-5000 km IME. I get around 7000 km out of the SP XLs. They're expensive, but better than anything else I've used.

Do you like the 35's best, mainly due to the extra width/contact over the 32's ?

Been running EL 32 on and off for the last year. Have to take it easy when downhilling over loose gravel w/hardpack underneath. Even more-so on off camber downhills, so the tire doesn't slide away.

[singlespeedscott]

I use the Stampede pass on my vintage steel and enjoy the ride and the look. However when riding a local gravel road, recently resurfaced with some really chunky stuff, I managed to pinch flat and put a small slash into the sidewall of the rear tyre, I was probably only doing 30km/hr when I did. I also was running 80psi in the rear. Any less pressure sees a lot more pinch flats and I find the tyre doesn't seem to climb as well for me. 60 seems fine in the front though.

[cameronp]

Anyone tried the WTB Horizon or Byway tyres yet? They're 650b x 47, the Horizon is slick and the Byway has side knobs. Looks like there are finally some more options than Compass in wide road-oriented 650b.

Been looking at building a gravel bike around the new Kinesis Tripster AT frame and going 650b is a definite possibility, but it's still a bit of a gamble. At least in 700c I know there are several tyres I get along with.

[Virgil Walker]

<<Do you like the 35's best, mainly due to the extra width/contact over the 32's ?>>
Yes. Better cornering on both gravel and asphalt. And I can discern no difference in aerodynamic resistance, though logically there must be greater resistance.

BTW I've never had any problems with sidewall damage on either Stampede Pass XL or BJP XL except once when I managed to drop a front tyre into an unexpected and unavoidable crack in the bitumen in the direction of travel on a bike path. It just scraped one cord of the carcass. IMO, any tyre would have suffered similarly. I still use the tyre.

I run the SP XL tyres at around 50-55 psi, tho I don't check them every ride and they sometimes go as low as 40 psi without much discernible difference in ride quality. Or not enough to worry me. I weigh 82 kg and often carry extra stuff for audax

At the recent LEL there were many bikes on Compass tyres (32-38 mm in 700c; 38-48 mm in 650b; and at least one, I think, on 54 mm 559).

[Virgil Walker]

PS If I get the chance, I'll get myself a set of 650b wheels even tho the biggest tyres I could run would be 38 mm. For my riding style and roads, I think they'd be excellent. (Disc brake frame.). If I could get a new frame, I'd set it up for 650b and 559 54 mm: the smaller wheels would be helpful for breaking down the bike for airline and train travel and I don't think I'd lose much or anything in speed.

FWIW What has caused me to DNF in audax events when it happened, has not been slower average speeds, but injury and/or bike damage due to falls, or adverse reactions to bad, inappropriate, or non-existent food. All of these are more to do with combinations of inexperience, lnsufficient planning or preparation, and fatigue. Beyond a certain level, the wheels and tyres probably don't make much difference. But wider more comfortable tyres might provide some benefits in comfort and stability and, with 650b and 559 wheels, slightly stronger wheels.

[hartleymartin]

Well, whatever the "hype" around 650B I am glad that its rising popularity means that there is now a decent selection of tyres and rims. I have just ordered some Marathon Plus 650B tyres (40-584) for my tourer and am looking to obtain some Velocity Atlas 650B rims (I am what you might call a "Clydesdale Class Rider" at 6'2" and 115kgs.) When I rode to Wombeyan Caves several years ago, I had 3 flats on the first day, and I am sure that my 32-630mm tyres did not appreciate having myself and all my kit for a 4-day fully-loaded tour.

[brasstinman]

I just recently picked up a GT Tachyon with 700D rims that are running 650B tyres specially for touring and audax rides. I've stripped the bicycle down down to clean and replace some bits and I'm very keen to start riding it. I don't have any experience riding 650B but I'm keen to get out there on them, everything I read about them is positive, well for countries where spares are in plenty. I'll cross that bridge when I get there.

[dubudu]

Hi All,

a slightly off topic question, has anyone tried the compass 26 x 2.3" rat trap pass. Thinking of building up an old mountain bike as a relaxed riding gravel bike. I have 650b 38mm pari-motos in my road bike and love them. Thinking the RTP should be really plush.

Cheers
Joe

[singlespeedscott]

I run rat trap pass tyres on my drop bar converted mid 90’s mtb. I’ve done a little over 1500km from single track to smooth hot mix. Mine are the standard casing as I feel the stuff I ride on could cut the sidewalls.

Obviously single track is not their modus operandi but on hard pack they are acceptable, anything lose needs to be ridden with caution.

For the forestry roads and rail trails, surface varying between sand through to fist sized rolled aggregate, they are perfect. They float through deep, dry sand and they absolutely fly on fire roads, seriously my mates on “gravel bikes” with 45mm tyres can’t keep up.

I have also used them on my commute to work and find they roll no slower than my 32mm stampede pass tyres. I still manage to average around 28kmhr for my 30km commute.

They are also an absolute ball on bitumen descents. They have that much grip that you can corner like your riding a moto.

If possible I would suggest you set them up tubeless to get the most out of them. It’s not that I’ve have found them puncture prone it’s just that I have had few pinch flats when running tubes with them. These tyres roll so fast off road that you really can smack into protruding rocks pretty hard.

[dubudu]

Thanks for the review Scott. Sounds wonderful. I was think of using them for foresty riding. You don't happening to have any old steel rigid mtn bike frames you feel like selling? Been looking around on gumtree, not much in Qld that I have seen. Steel, rigid fork and stays, canti. I don't have any experience with old mountain bikes, I guess clearance at the chainstays is the main issue.

[singlespeedscott]

Tyre clearance will not be an issue with an mtb and Rat Trap Pass tyres. Remember the standard in the early 90’s was 1.9 knobbies. The outside diameter is similar to the Compass tyres.

I don’t have anything suitable atm sorry. Keep looking, something will turn up. The style of frame you want is an early to mid 90’s hardtail. The geometry, other than the higher bottom bracket is nearly identical a modern “ gravel” bike. There is a guy from the US selling some NOS Cr Mo mongoose frames on eBay that should work.

Don’t limit yourself with a rigid fork either. I run my old bike with a Marzocchi Z2 atom bomb fork. A decent suspension fork with fat tyres will plow through anything whilst your mates on their skinny 45mm tyres and rigid forks are tip toeing around every bump.

[dubudu]

Thanks for the advice Scott. I had better not rush into this one. Was thinking of a rigid fork for a front rack, but there are plenty of options for storage these days, so yes, a suspension fork sounds like a great option.

[RobertL]

Thanks for the review Scott. Sounds wonderful. I was think of using them for foresty riding. You don't happening to have any old steel rigid mtn bike frames you feel like selling? Been looking around on gumtree, not much in Qld that I have seen. Steel, rigid fork and stays, canti. I don't have any experience with old mountain bikes, I guess clearance at the chainstays is the main issue.

I have an early 90's Shogun Trailbreaker frame and fork gathering dust. It's a biggish size - but I'm not sure what exactly (without looking closely).

You can have it if you want. Frankly, you'd be doing me a favour taking it off my hands.