Tuesday, January 20, 2009

Vintage bike ride...

A group of seven vintage bike kooks met up in Fairfax to take advantage of a holiday and the incredible weather we've been having. I spent the prior day getting my Ibis SS ready to ride. The one thing I wanted to do was get the Suntour XC Pro rear derailleur and right side Suntour 7-speed bar-con shifter back on the bike to get into the same configuration I had it when I first assembled the bike in 1991. It's now got all the original parts (except for tires) that it had 18 years ago.

Getting the rear derailleur cable installed, I almost had to pull out a tandem length gear cable. With the drop bars and bar-con shifters, a standard 2000mm length cable was the exact length needed with no trimming.

That's the end of a 2000mm cable.
From Vintage Bikes

I also retaped the bars with some new cloth bar tape and a wrap of cushy gel tape in the drop area. The combination of the cloth over gel was perfect with a pair of crochet back minimally padded gloves from Planet Bike.

After I got done getting the bike ready, for some reason, I measured the seat and head angles. The head angle is 72 degrees and the seat angle is 71 degrees. To the folks who ride bikes by reading geometry information, this bike probably shouldn't ride all that well. Well, that's hogwash. This bike rails. When I ordered the frame from Ibis, the SS model was available with custom options such as geometry. At the time, I asked for a 24" top tube. I got it. How Ibis did it, all the while keeping a tight wheelbase, was to increase the head angle to 72 and decrease the seat angle to 71 - and add a bit to the actual top tube length. What that did to the bike was keep the wheelbase to a nice 42 1/4" making the bike super fun to rail single-track. Another benefit of a tight wheelbase is that it climbs and descends switchbacks like nothing else. The steering is precise and the balance of the bike is just about perfect.

As I was riding the bike home the evening before the vintage ride, I realized that in the past 18 years, I probably lost some flexibility. In 1991, I set up the bar position where I liked it and had a custom LD stem made. To most off-road drop bar riders, my position is really low and on the pedal home, I was thinking the same thing. Most bikes I see these days have the dropped portion up near the seat height. My position is top of the bar 1 1/2" below the seat level and where my hands rest in the dropped portion is 6 1/2" below the seat. Again, on paper, probably not good, but is works well for me and as is evident from yesterday's ride, it works just fine through the more technical sections of the trail where I had nary a dab through the rocks and roots. All I can say is the bike is an absolute hoot to ride. While it felt low on the ride home, I adapted to the position and became very comfortable on the bike.
From Vintage Bikes

Another thing that came up yesterday was gearing. I think that, in some cases, today's ultra low gearing of 22 front/34 rear is maybe too low. Or rather, too low for rigid bikes. Gearing that low doesn't let the rider pedal through rough sections while keeping your butt just off of the seat letting the bike work its way through rocky sections. When the gear is such that you can pedal with force and keep your weight off the seat, you can roll through rough sections pretty darn easy. When the gear is too low, you have to sit with all your weight on the seat and pedal. On a rigid bike, spinning through rough sections is not the most efficient way through. Most of us yesterday were on 110/74 cranks with a 24t ring the smallest possible. I was also running a 30t large rear cog and another bike had a 26t for it's largest rear cog. Even with the climbing, I was never for want of an easier gear. In fact, I probably only dropped into the granny on one short section.

The other thing that was evident is wheel size. I don't think I could have had any more fun riding a bike with 29" or 650b wheels over this one with 26" wheels. I think as long as the bike is designed well, any one of those wheel sizes is going to ride well and not make me wish for a different wheel size during the ride. If you like what you got, then stick with it. Have fun. Enjoy the ride.

Like I said, the day was incredible. Forever views, single-track in great condition, temps in the low 70's, very slight breeze, and a bunch of good folks. Thanks for the ride, guys.

View south to Mt. Tam.
From Ride Photos

Fun trails.
From Ride Photos

Cool bikes.
From Ride Photos

(What's playing: Leaving, TX Father's Son)


Bushpig.vrc said...

Those cranks sound cool. Where do I get me some?

blackmountaincycles said...

Just start mis-hitting keyboard keys :-)

cyclofiend said...

Nice report. Thanks for sharing that. You folks look great out on the TR trails. What were the other bikes on the ride? I guess that three-tone one is a Klein, but couldn't quite get the details on that red/black number. - Jim

blackmountaincycles said...

Thanks, Jim. I realized after the fact that no one got any good shots of each individual bike. So, here's the list:

Early 90's Salsa ala Carte w/ Bontrager fork and WTB drop bars.

Bridgestone MB-Zip

1988 Salsa Custom (which used to belong to a friend I used to ride with in SoCal in the 80's).

Early 90s Rock Lobster w/ Action-Tec fork.

My 91 Ibis SS

A Bontrager of some vintage.

And finally, that Klein Adoit (the rider proclaimed "next time I'm bringing a steel bike")