A long-reach solution for wider bicycle tires

by Raymond Parker on April 11, 2011

in Cycling, Technical

We’ve discussed before the advantages of wider-profile bike tires. They are generally:

  • Faster
  • More comfortable
  • More stable
  • Safer

I had my Marinoni Sportivo “Randonneée” built specifically to accommodate fatter 700C tires (like my Marinoni Ciclo, the stock Sportivo comes with 49mm maximum short-reach caliper brakes, that will only fit 23mm tires with fenders).

That means, of course, that the rear seat stay length and brake bridge placement are optimized for 57mm medium-long-reach brakes. But what about forks?

That presents a bit of a problem as the great majority of stock forks, particularly carbon, are geared to the marketing of “racing” bikes, built for short-reach calipers, with a maximum reach of 49mm–too short to accommodate the larger tires preferred by cyclotourists, or randonneurs.

Depending on the bike, you might just squeeze a 25mm tire under fenders with short-reach calipers, but I’ll wager there’ll be trouble with mud and grit catching between tire and the inside of the fender.

So, where to find such a beast? My fork is made by Evo (Evolution), in Taiwan, the same (non-integrated “road-racing”) unit as on my Ciclo, but with the extra clearance. It has all-important fender eyelets and a traditional curved rake of 45mm. Marinoni used to carry these, but I think I got the last one. I’m not sure if they have replaced it with anything else. I’ll check.


Here are some other sources for long-reach forks in both carbon and steel:

Interloc Racing Design (IRD) | Origin 8 | Wound Up Composites

Related post: To 700C or 650B, that is the question

{ 2 comments… read them below or add your spin! }

Conor Ahern April 11, 2011 at 10:22 am

Excellent article Ray,

Here is a suggestion you have probably heard before. Would a Cyclo-Cross frame be more suited for Randonee riding, it already has a long wheelbase, slacker angles and plenty of clearance for wider tyres. It would be a cheaper option for someone who didn’t want to go the route of buying a custom built bike.

When I lived in Leadville, Colorado (highest town in the USA 10,200ft altitude) I used a Redline Conquest cyclo-cross frame and fork, that I then built up myself with a mix of parts, for winter training (winter lasted 9 months and it snowed all year). It could take wide tyres had plenty of clearance for mud guards (fenders) and had no problem clogging up with snow and ice whenever I got caught out in bad weather. When used as a training bike in the summer lack of speed was not an issue and it was nice and comfortable for long rides. When I returned to Ireland I used it as a touring bike, as it already had all the necessary eyelets brazed on for attaching racks. I have some photos of it somewhere that I could scan and send on.

I know that there are some restrictions on Randonee bikes, but it seems to me that a cyclo-cross frame and fork ticks all the boxes for what is required, and might prove a cost effective route for the beginning Randonneur.

Reply

Raymond Parker April 11, 2011 at 5:37 pm

Yes, Conor, a cyclo-cross bike, would make a functional rando bike. As mentioned on the rando bikes page, there are actually very few restrictions on what’s acceptable for a randonnée, other than the bike be safe and have lights for longer brevets (the exact rule varies by club).

The only downside I see is the higher bottom bracket generally found on a cross bike. That’s not a deal breaker but, if randonneuring was the only planned use, a touring bike is a good choice.

Both, of course, are usually equipped with cantilever brakes and have lots of clearance, as you say.

The readers’ rando bikes page illustrates a variety of approaches.

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