So my bike has a rain fender/mudguard on its rear tire, as seen here, and it does absolutely nothing. I still get a nice big muddy spackled wet skunk stripe up my back any time I ride around on wet roads.

I asked my local bike shop if they had any longer ones, or ones that attack to the rear wheel's center hub (which are also usually longer), and they said the only one they carry is the one I already have.

So does anyone here have any ideas how I can DIY extend my fender around the rear tire? I'm thinking a piece of curved plastic, two holes drilled into one end, and two holes drilled into the end of my current fender, and then bolting it on with small bolts.

You can extend it as you have in mind, but the reality is a long unsupported fended will whip around like crazy and may even get itself snagged on the wheel.

Also be aware that water doesn't leave a rear wheel radially, but tangentially. So to do you any material good, you'd have to extend the fender almost all down to the 3 o'clock position. You also would want to extend forward down to the chainstays so water isn't blasted at the bottob bracket.

IME, folks have two choices. They can either go bare, and take whatever nature throws at them, or they can go for full fenders with a flap at the back of the front one. Anything in between will be of marginal benefit, if any.

Get full fenders.

I thought of that, that's why I'll be attaching a coathanger spine for the whole thing with duct tape.

Yep, I am extending it to the 3PM position. Using an old ice-cream tub and a coathanger and duct tape and a drill and zipties

If I was willing/had money to buy something, I wouldn't be posting a thread about a DIY, now would I?

Go for it, and if you find whip to be a problem, you can improvise a brace out of coat hanger wire or somesuch, and attach it to the seat stay with an improvised P-clip. (It looks like our frame doesn't have fender eyes)


BTW- if the DIY doesn't work out, I have a bunch of new Planet bike fenders, and can sell you a pair for about half the going rate. Let me know if you're interested.

Get full fenders!

https://sheldonbrown.com/fenders.html

Just WOW!

Go for it, the worst that can happen is it doesn't work, I'm sure you'll figure something out.

since Get full fenders, was not in the plan .. Coroplast !

you can get a lot of it free from old lawn signs on the 1st wednesday in November,
but it will be contaminated by some politician's name and campaign fiction.

Coroplast would have been smart if I had read your post in time. And there's a member of (Canadian) parliament in the family, so we have a whole stack of lawn signs just sitting in the back yard! oh well.

Here's what my DIY fender thinks about all you naysayers:





Made using the plastic from a discarded tub of icecream, then made rigid with a coathanger spine that continues up part of the original fender, attached by drilling 2 holes into ends of both fenders and ziptieing together (probably should have used 4 holes and 2 zipties, but oh well).

The black duct tape covering it is because the way the plastic was curved, the ice cream label was showing on the outside. And I live in the type of neighbourhood where you don't want to have the words "red cherry" next to your ass, if you're male.

Went for a 20km ride today, and it had just rained this morning so the roads were all wet and dirty and full of puddles. I went over the puddles at full speed (something I would always avoid before), and the back of my shirt is COMPLETELY DRY AND CLEAN!!!! (well except for the sweat) Not once during the 20k did it even touch my wheel, despite the fact that it bounces around like crazy and should probably be attached to the rear wheel hub.

So it cost nothing, took 10 minutes to make, worked perfectly, and I got to say "TOLD YA IT WOULD WORK!" to everyone who doubted me. What a project

looks nice, go for a scraper bike to go with it

Planet Bike has commercial fender mud flaps for about $6.00. They don't even charge shipping because they consider them a replacement part for their fenders. Check their website carefully because they come in 2 lengths (the long ones are about 8") and 3 widths.

I don't understand, they don't charge shipping because they consider fenders to be replacement parts for their fenders? According to wikipedia, "fender" is a synonym for "mud flap", are you using the word 'fender' with a different meaning?

Either way, if I had $6 to spare, I wouldn't have bothered with a DIY one.

As near as I can tell, I used the term "fender" in exactly the same way you did in your original post. I'm thinking I used the term "mud flap" in the same manner as FBinNY. I'm amused that you researched wikipedia over this.

lol, didn't bother me m8, just didn't understand and was curious as to what you meant. sorry, I hope I didn't sound like an bumhole

Trust me, it takes a lot more than that to blip my radar.

I've always been interested in terms used to describe the same thing. For instance, "rubber bands" used to be called "rubber binders" in Minneapolis and "gum bands" in Pittsburgh. On the internet you often don't know what country another person is posting from so terms often vary.