650b x 45mm all-conditions tire?

[Matt Surch]

Hi folks, I'm struggling to understand why there is no 45mm tire on the market in 650b. I've got a Brodie Romax cyclocross bike that barely fits Compass Switchback Hills (48m), Panaracer GravelKing SK (48mm) and the Terrene Elwood (47mm). I can run them, but I get chainstay rub under power with a Woven Precision Handbuilts carbon rim (35mm deep, tubeless). I love the handling and ride height of the 47-48mm tires on pavement, gravel and trails. but I'm cutting it too darned close. Meanwhile, a bunch of my buddies can't fit the 47s at all. 

Does anyone know why 45mm options are not available? Am I wrong, missing something? Yes, I can and have run 42s, as have some of the guys, but the ride height we get is a little low for the trails we ride (singletrack with roots and rocks), and the extra volume of 47-48s really helps when smashing stuff. The Panaracer GK tread is pretty awesome for trail and gravel use, while the Terrene is awesome for lighter trail, gravel and pavement. Similar treads in 45 would be a pretty popular option, no?

[William Lindsay]

I don't think you are missing anything.  It's a size that some of us have wanted for a long time.  I doubt anybody on this 650B list will ever claim that gaps in the tire-availability spectrum are a good thing. 

I'm running a Niner RLT9 aluminum with 650B wheels, and I can't fit a 47-48.  I run Bruce Gordon Rock and Roads, and might try Compass Pumpkin Ridge next.  I'd try to run 45s if they existed. 

Bill Lindsay

El Cerrito, CA

[Matt M]

I've seen a few Niner RLTs with WTB Byways/Horizons. Do you have a XS frame or something?

[Igor Belopolsky]

Nice bike

http://teknecycling.com/velo-de-route-profile-brodie-romax-gravel-racer/

[gnr6...@yahoo.com]

650b 45mm tires is something I would welcome.  In my opinion, the 48 Switchback Hills fare much better on gravel with no downside on smooth roads in comparison to the 42mm Babyshoes.  But, the 48s are a difficult fit on my 650b bikes which are all vintage french.  A few millimetres larger than the 42s would be no trouble to fit, but the 48s fit larger than expected.

Something I have experienced is the the tire width of the Babyshoes tend to have a direct relationship to rim width.  Based on installing them on rims ranging from 17mm to 23mm internal widths  I have only used Switchbacks on rims with an internal width of 23mm or more.  I need to try them on a thinner rim to see how they function and how wide they measure.  Obviously a 45 tire would be a better solution than changing to thinner rims.

Reid

On Wednesday, June 6, 2018 at 3:33:11 PM UTC-4, Matt Surch wrote:

[William Lindsay]

I said my aluminum frame Niner RLT9 would not fit a 47-48mm tire

Matt M then said he has seen ‘RLTs’ with Byways and Horizons and asked if mine is an XS frame or something.

My aluminum Niner RLT9 is a size 59. The tight place is between the chain stays. Running actual 43mm tires the clearance is what I regard as a safe minimum for the riding I do. An actual 47 or an actual 48 might spin in the work stand without rubbing but I would not be comfortable with the clearance.

Are Byways and/or Horizons actual 47-48mm in width? I run 25mm outside width rims, so they might be i21?

[Kevin M]

I believe the steel RLTs have slightly more clearance. Maybe those are the bikes running the Byways?

[Justin Hughes]

Honestly, yes, I think you are in a minority so don't expect a true 45mm 650b tire anytime soon. The vast majority of the stock carbon fork options out there in this category fit 584-50 tires or larger with adequate clearance. To design a frame that has less clearance when one of these various fork options will be used doesn't make sense. It's just that you happen to have a bike (which sounds flippin' awesome BTW) that came about just before this era of lightweight and/or supple 2" 650b tires was settling in and it seems didn't really have both 700c and 650b in mind from the outset. It's a CX bike and no one races cross on 650b wheels so it's no fault of the bike.  

On Wednesday, June 6, 2018 at 3:33:11 PM UTC-4, Matt Surch wrote:

[Justin Hughes]

Yeah, I would rather ride tubeless BSP ELs on i25 rims than tubeless (or tubed) SBH ELs on i17-18 rims. 

Justin

[William Lindsay]

Yes Kevin, that is my understanding as well that the steel RLT9 frame has a bit more clearance at the chainstays.  If I could wave my magic wand and make my RLT9 aluminum transform itself into an RLT9 Steel, I would definitely do it.  Unfortunately the closest thing I have to a magic wand is a credit card. 

Bill Lindsay

El Cerrito, CA

[Matt Surch]

I’d not suggest decreasing clearance in forks, nothing gained there. Yes, my frame was designed without a tonne of 650b consideration, but it’s so common in this regard. Virtually everyone I know with a cx bike can’t fit a 47mm tire properly. It’s not that I want to run 45s, but that the lack of an option in this size is keeping a lot of people from getting 650s. My actually preference is to have 2.1” clearance, and my next bike will have that. It just sucks not being able to point friends to a setup that works on their existing bikes.

[Matt Surch]

Thanks, Igor!

[Nick Favicchio]

Elwood and Switchback have measured 45mm on the 23mm wide rims I ride.

But there does seem to be a gap, bc the "42mm" tires tend to measure 40mm.

I've been running 42 out back and 47 up front. Add them up and divide by 2, works perfect :).

https://www.instagram.com/p/BkwAs_8BuW6/?utm_source=ig_share_sheet&igshid=k8nktoncb6fy

[cmontgo...@gmail.com]

I'd be on a 45mm tire at the drop of a bottom bracket. Tried running Switch Back Hills on my Riv All Rounder but there's only a mm or two between tire and brake bridge. No fenders. Unacceptable. Converted back to 559's and am running Rat Trap Passes:  https://www.flickr.com/photos/24722971@N05/41902748951/in/dateposted/    But would prefer 584's with 47-48's. With fenders. 

But if someone came out with a quality 45mm I'd be there. In the meantime I'm in search of a frame that'll handle 650x47-48's with fenders. With a level top tube and cantilevers. 

Craig in Tucson

On Wednesday, June 6, 2018 at 12:33:11 PM UTC-7, Matt Surch wrote:

[Joe Rosario]

Anyone using the Kenda Flintridge Pro 650b x 45?  Wondering if they measure true to size.

Joe

[Paul Choi]

The Flintridge Pro 650b looks like a great gravel tire. It has some good reviews on the Kenda site.