Friday, June 14, 2019

650B Ride Report

After a Thursday with nothing but rain and cooler temps, Friday turned out to be a beautiful day for riding. We had brilliant skies, low humidity, and temps in the upper 60s. Perfect. I decided to take the 650B Motobecane out for a real test ride. I headed down into the valley and followed some of the "roads less traveled." In fact, if you're in a car, some of the roads have been rendered inaccessible altogether.

There's an old covered bridge in the valley that's 
been closed to cars for at least a couple of decades now. 
If you've been following the whole conversion story, you know that I started the project with a 25" frame (about 63cm), even though I usually ride 24" (or about 60 - 61cm). With the smaller wheel size, the standover still works for me, and I can get the bars at about the same level as the saddle quite easily. There's a small "fistful" of seat post showing - obviously a little less than on most of my other bikes. My one concern was if the reach to the bars would still work - but the top-tube length isn't really much longer than on most of my other bikes. I used a 9cm stem instead of my usual 10cm, and the reach felt pretty good.

One of the first things I noticed when riding the bike is that the tires (38mm) really do a great job of smoothing out the roads. Our roads are in about the worst shape I can remember - our winters have been terrible on the roads these last few years because the temperatures fluctuate so much throughout the season, resulting in endless cycles of freeze/thaw, freeze/thaw - and that is hellish on asphalt. But these wheels/tires really seem to subdue the chatter. I mean, that's always been the big selling point of 650B, isn't it? Well, I have to say that the hype is true on that score. On gravelly sections, I felt like "Gravel? What gravel."

Road Closed - not to bikes however. Our county roads department recently voted to permanently close this road leading to the covered bridge from the north and end all maintenance for it - in other words, let it go back to the wild. Cyclists petitioned to have it maintained for bike and hike uses, but that was denied. There are larger barricades than these, but they can't really keep the bicyclists out. Still, the pavement is really starting to deteriorate. I've ridden through here on other bikes with narrower tires, but the 650B wheels and tires really make a difference. Really smooth.
Another thing I noticed was the handling. I don't know if the handling is altered significantly from what it would have been with the 27" wheels it was originally designed for (or even 700C), but the bike feels "zippy." That's the best word for it. It changes direction quickly, with very light input - yet it tracks straight and rides easily no hands. I guess that shouldn't be a surprise - that head angle must be 74 degrees! I still cannot believe that this bike was described "back in the day" as a touring bike. I did worry a little about toe-clip overlap - but it isn't an issue. There is one tiny spot in the crank rotation where the leading tip of a toe-clip can just barely "kiss" the back edge of the fender, but the likelihood of it happening is so slight, and even if it happened, it would be inconsequential. If it were fenders over 700c or 27" wheels, it might be a problem.

A friend had told me that I might find the bike a bit slow going uphill. Other things being equal, I cannot think why that would be the case. Why would a bike with 650B wheels climb any more slowly than 700C? Maybe if one were using heavy rims/tires it could make the bike feel slow, but it seems to me that I made some smart choices in that department. Anyhow, my ride today had several hills in it - some pretty steep - and ALL my rides end with a long difficult climb out of the valley. I just did that out-of-the-valley climb last week on my "racy" green Mercian, and did not find the 650B Motobecane to be noticeably slower. I mean, I didn't time either climb, but it certainly didn't feel any slower. However - it's worth noting that switching to smaller wheels will absolutely lower a bike's overall gearing. Between 700C with 28mm tires and 650B with 38mm tires, there is a gearing difference - albeit a small one - in terms of "gear inches" it would probably reduce the gear by an inch or less. Would someone be able to feel that difference? I don't know. I did find that I rode in the large chainring a little more than I might have done otherwise.

I did alter my gearing slightly since I posted my report on the finished bike and listed all the specs. I had originally installed a 5-speed freewheel with a range from 14 to 28 teeth. It's difficult to find a 5-speed freewheel with cogs smaller than 14 teeth. Looking through my freewheel collection, I found that I had a SunTour Winner "ultra 6" (a narrow-spaced freewheel meant to fit into the space of a 5 speed) that was 13 to 26. That gave me a slightly higher high gear, and the low gear (with a 34 tooth chainring) is plenty low enough for me. And I picked up an extra gear in the middle. The shifting on the narrow freewheel is smooth, quick, and quiet. And the old SunTour ratcheting bar-end shifters work great.
I stopped at the produce market - of course. It was a lot busier than it looks here.
Well, it happened. I've just become one of those goofs who takes pictures of their food and posts them to social media. The farm market sells big "deli dogs" that are pretty awesome. Topped here with vidalia onions and brown mustard. They also have grilled corn on the cob, but I skipped that today.
Was there a downside? Well - brakes. Looonnngggg reach brakes like the DiaCompe 750s seem to work just fine riding around town. But on a long fast descent, I did find them to be a little slow in stopping. They have a nice, light feel at the lever - but I'm guessing that there's enough flex in the long arms and the yoke, etc., that the brakes really lose some efficiency, or as some would describe it, "power." I have a feeling that they'd be improved mightily by having the posts brazed directly to the frame/fork. If I ever send the frame out for paint and modifications, I'll definitely have posts brazed on.
Despite the chips, scratches, and touch-ups,  the old Motobecane really gleams in the sun. All that shiny aluminum really catches the sun too. I'll never get the current fashion for black bike components.
Wrapping up, everything on the bike worked as I'd hoped. The fit felt good all around. We had some pretty strong winds, and I spent a lot of time comfortably down in the drops. I think the best mission for this bike will have to be in looking for more "off the beaten path" routes - more gravel roads and unpaved paths. That's where those 650B wheels will really shine.


  1. Brazed on posts for normal reach brakes should really improve the braking. Paul racer centerpulls would also help, but you would lose the more classic appearance of the Dia Compes.

    1. Dia-compe still sells the centerpull posts for their brakes. There's also always the option of classic cantis if you don't want to limit brake availability.

    2. I'd probably use the DiaCompe ones - the DC brakes are practically ubiquitous- So parts are easy to get, cheap, and (if looks matter) they can actually be polished up pretty nicely.

  2. After a long period of skepticism about the touted benefits and great ride qualities, I had a low trail 650B frame built last year by Mike Terraferma of Miami.
    He built the frame and I did the mechanical build myself.
    I call it a magic bike. Outfitted with 650B x 42 it rolls fast and smooth and oh so comfortable.
    I had been riding a retrofitted Trek 720 which until the fateful day I first rode the new rando bike was the nicest riding bike I ever owned.
    One ride on the new bike and I put the Trek up for sale because I knew I would never ride it again.
    I humbly admit to being a happy convert.
    Randy R