The front fender on my Radrunner wasn't long enough to keep dirt and water off my controller, chain, and feet. I've had stuff like this lying around for 30 years: https://amzn.to/3Mxde2V
It's almost as thick as the fenders. I cut a piece and marked where I wanted the edges bent. To bend, I sandwiched the piece between sticks in a vise. A hair dryer didn't get it hot enough, so I used a propane torch with a flame spreader. An electric heat gun would have been better.
My pop rivet gun was made for two hands, so it was tricky to hold the washer in place until I could pull the rivet tight enough to hold it.
The fender is generally 30cm from the axle, but the bottom of the extension is 36cm out. That's partly because the bottom lip of the fender curls out. I can avoid that by bending an extension to fit under the fender, not over it.
If the handlebar is turned sharply, there's about 2.5" between the pedal and the extension. My toe doesn't seem to extend that far in front of the pedal. On a test ride, I found that I don't steer that sharply except in a u-turn. I've still got clearance. What's more, if my toe ever did hit the fender, it wouldn't get caught because my toe would be moving downward.
Great !!! Will do the same for my bike
I did the same thing on my radwagon yesterday using a rubber-sheat
(https://uploads.tapatalk-cdn.com/20220425/004abdf37f933d5906988c6f645625a3.jpg)
Quote from: Runningliner13 on April 24, 2022, 04:13:40 PM
Great !!! Will do the same for my bike
Uh-oh! I made measurements and did math. It looks as if the original would let water and grit fly up at 71 degrees above level, so it wouldn't protect much below the rider's face. It looks as if the extension would let the tire shoot stuff up at 42 degrees above level. That would protect a rider above the knee but it looks as if it wouldn't protect shoes, chain, and controller. Maybe there's a way to test it on wet pavement.
The extension comes down to about 8.5" off the ground. I think a motorcycle front fender is 6" off the ground. My extension is strong. I think I'll rivet another extension to it.
Quote from: malajo on April 24, 2022, 08:24:53 PM
I did the same thing on my radwagon yesterday using a rubber-sheat
How thick is it? Where can I get some? I want a longer extension than I have.
This is a my design
Quote from: Runningliner13 on April 26, 2022, 04:27:10 PM
This is a my design
Looks good.
I want to extend mine, and I saw a potential problem. Mine stuck out too far from the tire for a low fender. Greater distance behind the tire's contact patch increases the likelihood that a low piece will hit something. Within an inch of the tire, the Raleigh Roadster's fender was only 3" from the pavement. The Raleigh Sports fender was equally close, but 5" from the pavement. It was for people who might have to move it up or down steps to get it indoors at night.
I made a new extension to fit inside the fender. The bottom is an inch closer to the tire than the first one. Before I lengthen it with a second extension, I'll see if I can bend it closer with a heat gun.
I made one from chopping board. I might add few pop rivets.
Quote from: Kari on April 30, 2022, 08:44:16 AM
I made one from chopping board. I might add few pop rivets.
It looks as if yours would flex like a mud flap if it hit an obstacle. That's one solution.
Quote from: handlebar on May 01, 2022, 08:14:11 PM
Quote from: Kari on April 30, 2022, 08:44:16 AM
I made one from chopping board. I might add few pop rivets.
It looks as if yours would flex like a mud flap if it hit an obstacle. That's one solution.
Yes, and very wise. When the flap is that low just going slowly down a small curb can catch it. If the material is hard and low the curb can damage not just the flap but put all that downward force straight up pulling or ripping the fender off the mounting struts.
This is why most fender manufacturers use rubbery material.
Quote from: Radio Runner on May 01, 2022, 11:56:26 PM
Quote from: handlebar on May 01, 2022, 08:14:11 PM
Quote from: Kari on April 30, 2022, 08:44:16 AM
I made one from chopping board. I might add few pop rivets.
It looks as if yours would flex like a mud flap if it hit an obstacle. That's one solution.
Yes, and very wise. When the flap is that low just going slowly down a small curb can catch it. If the material is hard and low the curb can damage not just the flap but put all that downward force straight up pulling or ripping the fender off the mounting struts.
This is why most fender manufacturers use rubbery material.
After test ride: it's quite noisy on dirt roads when small rocks and other partikles hit it. It could be few cm narrower and shorter. Few ground contatcts on bumps. It's flexible material, but that curvy shape stiffen it.
But at least my feet and controller box are dry.
Quote from: Radio Runner on May 01, 2022, 11:56:26 PM
Quote from: handlebar on May 01, 2022, 08:14:11 PM
Quote from: Kari on April 30, 2022, 08:44:16 AM
I made one from chopping board. I might add few pop rivets.
It looks as if yours would flex like a mud flap if it hit an obstacle. That's one solution.
Yes, and very wise. When the flap is that low just going slowly down a small curb can catch it. If the material is hard and low the curb can damage not just the flap but put all that downward force straight up pulling or ripping the fender off the mounting struts.
This is why most fender manufacturers use rubbery material.
That concerns me, but for 10 years I rode bicycles whose fenders were 5" off the ground, without trouble. For decades, I rode motorcycles with fenders 6" off the ground without trouble.
My 1961 BMW had an old-school "box" fender, like the Radrunner. The fender and the fairing kept me amazingly dry in heavy rain. My 1970 BMW had a fender that was a 45-degree arc. It was stylish but didn't work. My boots would fill with water on a wet highway. I think the wind blew the water out from the shallow arc.
That's why I like the idea of a boxy extension. A heat gun is helping me shape it closer to the tire. I wonder if I could use plastic automotive fasteners instead of pop rivets. I'd rather have the extension break away than ruin a $100 fender.
Handlebar,
Yep, you can get away with it for a long time but when/if it happens it can be pretty catastrophic. Here is a pic of my old English Mercian. I was using SKS Long Board fenders when a simple pine cone bounced up and jammed up the works. Almost went over the bars.
Quote from: Radio Runner on May 02, 2022, 03:30:49 PM
Handlebar,
Yep, you can get away with it for a long time but when/if it happens it can be pretty catastrophic. Here is a pic of my old English Mercian. I was using SKS Long Board fenders when a simple pine cone bounced up and jammed up the works. Almost went over the bars.
That takes me back. When I was 6, my 7-year-old sister came up with $10 for a Jackson, which was really a 26" Raleigh Sport smuggled in as motorcycle parts. It was an adult bicycle, but the seat tube, swept back 30 degrees, meant that it could be adjusted for someone as small as me. Before long, politics put an end to that, depriving American kids of decent bikes. (When I was a teen, every kid seemed to own a Schwinn, and every Schwinn could be found gathering dust in a garage or basement.)
At 14, I finally had the money for a Jackson. I found one so decrepit that the fenders were perforated with rust, but I gladly paid $20. My homicidal brother was waiting at home. I must have been going at least 10 mph as I rode past, because I was in high gear. From the right, he hit the back of my front wheel with a basketball. One would expect this to cause the wheel to swerve, causing the rider to go over the bars and perhaps break bones or be killed. The Jackson had such a stable riding position that my bars stayed straight. However, the decrepit fender crumpled against the top of the fork, locking the tire. I went over the bars, but because I'd kept them straight, I could spring over them in a somersault. I landed on my feet with my wrecked bike behind me.
The only wrecked part was the fender. I walked two blocks and for $2 bought a new Raleigh fender. Kids couldn't afford Raleighs, but adults who owned them rode them for many years and needed parts.
Some SKS Long Beards seem to flare away from the tire at the bottom. I think that's asking for trouble. I've been working with a heat gun, a bungee cord, and leather gloves to shape mine closer to the tire before adding another extension. I quit because of my crippled thumb, but it's much better. Meanwhile, I've been trying to find out about plastic fasteners used in automobiles. They even make plastic pop rivets. The 3/16" size breaks at 100 pounds. I guess that's too strong.
Quote from: Radio Runner on May 02, 2022, 03:30:49 PM
Handlebar,
Yep, you can get away with it for a long time but when/if it happens it can be pretty catastrophic. Here is a pic of my old English Mercian. I was using SKS Long Board fenders when a simple pine cone bounced up and jammed up the works. Almost went over the bars.
I found Amazon reviews of Long Boards. The bottom appears to be only an inch off the pavement. That and the flare show why a pine cone could mean destruction. I wonder why it wasn't designed with breakaway fasteners.
I should put a review up with my picture now that you mention it. I bought them at a shop so it never occurred to me.
I thought they looked like trouble (and was right) I'm willing to venture that SKS won't be making them long term. It's just to easy.
Quote from: Kari on April 30, 2022, 08:44:16 AM
I made one from chopping board. I might add few pop rivets.
Do you know what kind of plastic it is?
This looks promising.
https://amzn.to/3MmdAJT
It's polypropylene, 5mm thick. Polypropylene is used for hinges because it can bend a lot of times without deterioration. It's a thermoplastic, which means it can be heated to melting without degradation. The usual melting point is 266 F, which is easy for a heat gun. It's not good for machining because it deforms at a low temperature. Maybe that means it could be reshaped well below the melting point. I want to shape it with sides to keep water from blowing around it. Maybe I could put one or more notches in each side so that if it hit something, it could flex instead of tearing the fender.
Quote from: handlebar on May 06, 2022, 01:18:54 PM
Quote from: Kari on April 30, 2022, 08:44:16 AM
I made one from chopping board. I might add few pop rivets.
Do you know what kind of plastic it is?
This looks promising.
https://amzn.to/3MmdAJT
It's polypropylene, 5mm thick. Polypropylene is used for hinges because it can bend a lot of times without deterioration. It's a thermoplastic, which means it can be heated to melting without degradation. The usual melting point is 266 F, which is easy for a heat gun. It's not good for machining because it deforms at a low temperature. Maybe that means it could be reshaped well below the melting point. I want to shape it with sides to keep water from blowing around it. Maybe I could put one or more notches in each side so that if it hit something, it could flex instead of tearing the fender.
I guess plastic cutting boards are usually polypropylene. I have one 9mm thick, and that leads me to believe that even 5mm might be too thick for this purpose.
https://amzn.to/3yIFJqS
This might do. The flexible ones seem to be 1mm thick as a rule. These are 1.3. I found an old plastic cutting board on a shelf. It's 0.63 thick. It feels as if it could work. I think one twice as thick (1.3mm) would be adequate but not strong enough to wreck my fender if the extension hit something. Polypropylene can't be painted, so I'll have to chose a color from the pack.
Quote from: handlebar on May 06, 2022, 01:18:54 PM
Quote from: Kari on April 30, 2022, 08:44:16 AM
I made one from chopping board. I might add few pop rivets.
Do you know what kind of plastic it is?
This looks promising.
https://amzn.to/3MmdAJT
It's polypropylene, 5mm thick. Polypropylene is used for hinges because it can bend a lot of times without deterioration. It's a thermoplastic, which means it can be heated to melting without degradation. The usual melting point is 266 F, which is easy for a heat gun. It's not good for machining because it deforms at a low temperature. Maybe that means it could be reshaped well below the melting point. I want to shape it with sides to keep water from blowing around it. Maybe I could put one or more notches in each side so that if it hit something, it could flex instead of tearing the fender.
2 mm thick polypropylene.
But small touch to the terrace board was too much for it.
Quote from: Kari on May 07, 2022, 09:00:12 AM
Quote from: handlebar on May 06, 2022, 01:18:54 PM
Quote from: Kari on April 30, 2022, 08:44:16 AM
I made one from chopping board. I might add few pop rivets.
Do you know what kind of plastic it is?
This looks promising.
https://amzn.to/3MmdAJT
It's polypropylene, 5mm thick. Polypropylene is used for hinges because it can bend a lot of times without deterioration. It's a thermoplastic, which means it can be heated to melting without degradation. The usual melting point is 266 F, which is easy for a heat gun. It's not good for machining because it deforms at a low temperature. Maybe that means it could be reshaped well below the melting point. I want to shape it with sides to keep water from blowing around it. Maybe I could put one or more notches in each side so that if it hit something, it could flex instead of tearing the fender.
2 mm thick polypropylene.
But small touch to the terrace board was too much for it.
That's what I like to see! An extension that can give way without damaging your fender. It looks like 6" off the ground. If it could have been shaped closer to the tire, it might not have hit.
The nature of your break gives me an idea. Maybe I can cut a couple of vertical slits to let the polypropylene extension give way and spring back. I guess the proper approach is to drill a couple of holes and cut the slit between them.
Quote from: Kari on April 30, 2022, 08:44:16 AM
I made one from chopping board. I might add few pop rivets.
The cutting boards I bought were supposed to be 1.3mm thick. Actually, they're 1.0mm polypropylene with 0.3mm dots of silicone rubber on the back to reduce sliding. 1.0mm polypropylene seems plenty strong, but I doubt it could damage my fender.
It comes off the fender at such an angle that I had to bend it sharply with heat. The folds don't look good, but they seem durable. It's 5.5" off the ground and so close to the tire that damage is unlikely.
I think I can do better by skipping the side rivets and using the center rivet and the screws for the fender wire. I can shim it at the rivet so I won't need a radical bend. The sides are 1/2". I'll try 1/4", to curve better without folding.