23 October, 2009

Another Fender Trick

How do you do mount a fender on a bike without a screw hole in the chain stay bridge? A P-clamp around the chain stay bridge solves the problem. This trick works on seat stay bridges too. But if you don't have a bridge at all things get more complicated.




It's surprisingly hard to explain, over the phone, how a fork crown daruma works. Perry made this great sketch that says it all. Note that all VO fenders now get Daruma bolts rather than front L-brackets.


Past fender trick can be found here and here. Fender mounting instructions can be found here. And there is an article about choosing fenders here.

Finally, there are some clever riffs on daruma bolts and fender mounting at Patricks an open sketchbook blog.

20 comments:

Dan said...

i just ordered some p-clamps for this purpose. i was actually thinking of mounting them with the screw down. would you care to perhaps touch on if the chainstays are a bit too narrow (2-3mm) at the bridge? i've read various techniques, which involve cutting (outch!) and crimping. i favor the latter, but lack some good advice in this department. thanks!

philcycles said...

I prefer to braze a piece of steel with a 5mm threaded hole in the bottom of the steerer. That way you aren't dependent on a brake bolt. I thread a hole so that if you strip it out you can use a Rivnut. But please, don't strip it.
Phil Brown

reverend dick said...

Star flange nut hammered up the underside works just fine here, fellas.

Gunnar Berg said...

Dan,
Notch the fender. I think it's neater in the long run.

Kilroy said...

Greetings,

It's good you have included these helpful hints on installing fenders. I've used several manner of things, of which salvaged parts from old brake sets work the best for me. That spring loaded set up seems to fit the bill.
It's discouraging that we have to accomodate fenders (somewhat of a necessity) on bicycles which don't seem to have been built with that purpose in mind. Hopefully, future bicycles will not have this downfall. Have we regained our senses?

Best regards

rcs said...

Interesting... might have to try that on my '59 Raleigh Lenton frame - the chainstay bridge is drilled top-to-bottom, not front-to-back. Any recommendations for this situation? How might the fender have been originally secured?

Joel said...

I experienced a bizarre mechanical failure with a daruma bolt set up a few years back.

Bike was a Homer Hilsen with the extra long Honjo hammered (VO sourced, of course) fenders and Silver (tektro) extra long side pulls.

Some debris caught between the wheel and fender. Wheel siezed cramping the fender. Somehow the fender cramped with enough force to bend the center mount brake bolt.

I had to release the brake wire and ride home without front brakes. It was very difficult removing the center bolt and daruma.

Not saying this because I disagree with using the set up. In fact, I have a bike set up that way now. Just interesting all the bizarre things that can go wrong with something as apparently as simple as a bike.

David Benson said...

In the absence of a chainstay bridge,I have used a Blackburn taillight bracket to locate the front of a mudguard:
http://tinyurl.com/ygyxymf

frankenbiker said...

All great ideas guys thanks for the tips.I think I may use the Daruma or upside-down star nut idea(nice idea Reverend Dick) to mount the front fender on my new commuter/city bike.Thanks again and perfect timing for me!!

Jim G said...

What to do if your bike doesn't have a chainstay bridge...

http://www.flickr.com/photos/jimg/478664219/

http://www.flickr.com/photos/jimg/478664247/

Garrett Belmont said...

Great ideas.

I was looking for alternatives for the toe clip grabber. The little SS VO p-clamp trick looks great (and I have extras).

I'm planning to get the daruma, but I'm waiting so I can piggy back on another order. Maybe I'll get the orange tape!

Anonymous said...

If you can't find the proper p-clamp size you can just use one of those zip-ties that come with an eyelet.
more here

frankenbiker said...

Jim G., get creative with a couple of nuts and bolts and metal reflector brackets.Bend'em up with pliers to the desired shape and WHAMMO!! fender bridge.Hop this helps.

jimmythefly said...

Another no-bridge solution is to use a piece of flat metal from the BB cable guide mounting bolt.

Chris, I like the new blog background overall. But, the posts need a bit more space or something to define where one post ends and another begins. I find something about the text/font/spacing/etc. to be a bit awkward.

Raiyn said...

I'd like to pick your brains if I could.

I'm looking for a way to approach the top fender mount on a suspension corrected MTB fork such as my Surly 1x1. As you probably already know, frames built for suspension forks are designed so that the bottom end of the head tube will normally be higher up to make room for the suspension fork's travel.

Suspension corrected rigid forks mimic this geometry, they have longer blades to hold the head tube up to the same height a suspension fork would, this creates a larger than normal gap between the crown and the tire making normal fender installation more difficult.

I've seen plenty of kludged extensions, usually involving a piece of sheet metal used to bridge the gap between the crown and the L bracket, but they almost always look like something that was assembled by a chimp.

I have an idea of my own, and while I have to admit my plan is sheer elegance in its draconian complexity, I wanted to see what solutions the VO folks might come up with.

Jim G said...

@frankenbiker -- I'm not visualizing your hack from your description. Do you have a photo? FWIW, I did consider the "metal strip from the BB guide" trick, but my reflector-clamp+L-bracket solution seems more solid. It works great!

jimmythefly said...

Raiyn:

Install a star nut under your fork crown. Use some combination of long bolt and tubular spacer to direct-mount your fender (no L bracket needed).

Or,
If you've got canti/v-brake posts, you could also obtain or fab a brake-booster type arch and use that as a fender mounting point.

That's all I've got. Though I admit to using a bit of that slotted flat bar that comes with blackburn racks to buid an extension from the crown, and if done right I don't think it's too kludgy.

Raiyn said...

@ JimmytheFly

The long spacer idea has some merit, but it would kinda lock you into one size tire.

The brake booster idea on the other hand is exactly what I was thinking, although the L-bracket would need to be moved in order to compensate for the forward position (nearly three inches from where it's supposed to be attached)

I've got a set of Brand "N" Brake Boosters and they have a center slot that would make them ideal for this sort of mount. The only issue I have is centering the bracket on the fender. I wonder if it would work to use something like a sliding bracket and then run a bolt through that. Ideas?

Tom SVDP said...

Oh dear, I need to order some of these, could these work with a front constructeur rack if you did not have the outlets on the fork but of course, the Motobecane! has the fender outlets. Anyone can feel free to respond. Thx.

Anonymous said...

how do i put fenders on a stingray frame that has no holes for screws?