mud flap or parachute?
#1
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mud flap or parachute?
I just finished making a mudflap from vinyl for the front of the bike using the dimensions in this link. https://phred.org/~alex/bikes/fendermudflap.html
But when the bike is moving the flap and parachute's backwards and hits the pedal. How can I reduce wind reistance yet protect the bottom bracket (and keep myself drier)?
But when the bike is moving the flap and parachute's backwards and hits the pedal. How can I reduce wind reistance yet protect the bottom bracket (and keep myself drier)?
#2
1. Try a heavier or stiffer material.
2. Add a stiffener like an aluminum strip running the length of the flap.
3. You could bolt some weight like washers to the bottom of the flap but be careful that it cannot swing forward and get caught up in the tire.
2. Add a stiffener like an aluminum strip running the length of the flap.
3. You could bolt some weight like washers to the bottom of the flap but be careful that it cannot swing forward and get caught up in the tire.
#3
Coat hanger! Couple of ways to do this really. You could glue it to the inside. or mount it to the outside to make a metal support that makes it stay in place. I perfer the inside process with apoxy.
#4
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Originally Posted by GyverX
Coat hanger! Couple of ways to do this really. You could glue it to the inside. or mount it to the outside to make a metal support that makes it stay in place. I perfer the inside process with apoxy.
Got any close up pictures of this?
#5
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From: Montréal (Québec)
I followed approximately the same model for both front and rear mudflaps. I have used rubber sold by the metre to cover carpets in Winter. There are two thicknesses around here, and I find the heavier thickness works better because it's stiffer.
My front mudflap doesn't move, but the top part is curved inside the fender, which I think is what makes it stiff and prevents it from catching in the wind. My rear one moves, but it's longer and wider, because it supports reflectors.
You might try to make sure the top part is well seated into the curve of the fender. Or you might add a small piece of stiff plastic (a milk jug, for instance) near the top.
My front mudflap doesn't move, but the top part is curved inside the fender, which I think is what makes it stiff and prevents it from catching in the wind. My rear one moves, but it's longer and wider, because it supports reflectors.
You might try to make sure the top part is well seated into the curve of the fender. Or you might add a small piece of stiff plastic (a milk jug, for instance) near the top.
#6
https://www.bikeforums.net/attachment...id=15013&stc=1
Nope, Never done this before, JUst thought of it. but here is sort of an illistration of what I was talking about. The red is the coat hanger but think of it on the inside, not the out side. Your main concern here is two points. the top of the hanger that is placed with in the fender. this has to be a strong glueing. then the bottom. The bottom doesnt need to be as strong but it needs to have some good glueing. the rest is just forming.
I hope this helps
Nope, Never done this before, JUst thought of it. but here is sort of an illistration of what I was talking about. The red is the coat hanger but think of it on the inside, not the out side. Your main concern here is two points. the top of the hanger that is placed with in the fender. this has to be a strong glueing. then the bottom. The bottom doesnt need to be as strong but it needs to have some good glueing. the rest is just forming.
I hope this helps
#7
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WHEW! I thought I was the only one that had that idea.
I"m planning on making mine out of tire tube rubber, although the tube I"m using is from a tractor's rear tire, so it's HAYUGE.
My mudflaps are going to be a bit different in design, though, as I'm planning on making mine also extend outwards from the sides of my fenders. I've got a mountain bike I'm rigging to be more of a 'cargo carrier', for commuting purposes. I've kept the mountain tires, though, because the 'lugs' on hte side provide me some critical traction when cornering. The drawback, though, is that the lugs manage to fling mud OUT in addition to UP, so I'm still getting sprayed. As wider fenders don't seem feasable, I"m simply extending mine with the tractor tube tire.
I hadn't thought of attaching them with punch rivets, though...great thought...
But I've had temporary flaps tacked on around the outside of the fender for a bit, slashed rubber like the 'fringe' mudflaps seen on some semi trucks, and I've never had a problem with them blowing. The 'fringe' seems to let the air through without a problem, but the mud sticks to them pretty well, enough to break the initial inertia that would throw it up at someone's face or feet.
I"m planning on making mine out of tire tube rubber, although the tube I"m using is from a tractor's rear tire, so it's HAYUGE.
My mudflaps are going to be a bit different in design, though, as I'm planning on making mine also extend outwards from the sides of my fenders. I've got a mountain bike I'm rigging to be more of a 'cargo carrier', for commuting purposes. I've kept the mountain tires, though, because the 'lugs' on hte side provide me some critical traction when cornering. The drawback, though, is that the lugs manage to fling mud OUT in addition to UP, so I'm still getting sprayed. As wider fenders don't seem feasable, I"m simply extending mine with the tractor tube tire.
I hadn't thought of attaching them with punch rivets, though...great thought...
But I've had temporary flaps tacked on around the outside of the fender for a bit, slashed rubber like the 'fringe' mudflaps seen on some semi trucks, and I've never had a problem with them blowing. The 'fringe' seems to let the air through without a problem, but the mud sticks to them pretty well, enough to break the initial inertia that would throw it up at someone's face or feet.
#8
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Originally Posted by DragonMistress
But I've had temporary flaps tacked on around the outside of the fender for a bit, slashed rubber like the 'fringe' mudflaps seen on some semi trucks, and I've never had a problem with them blowing. The 'fringe' seems to let the air through without a problem, but the mud sticks to them pretty well, enough to break the initial inertia that would throw it up at someone's face or feet.
#11
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Originally Posted by madpogue
Some models of Planet Bike fenders have built-in mud flaps.
Are REAR flaps actually necessary if the bike has a full fender**********? Seems like overkill.
Last edited by vrkelley; 08-11-04 at 10:38 PM. Reason: adding picture for clarification
#12
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Originally Posted by vrkelley
Wow these are about 1/3 the length of the ones posted at the top of the thread.
Are REAR flaps actually necessary if the bike has a full fender**********? Seems like overkill.
Are REAR flaps actually necessary if the bike has a full fender**********? Seems like overkill.
As for the size, you might be able to mount the fender lower.
#14
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From: Boulder, CO
Bikes: Salsa La Cruz w/ Alfine 8, Specialized Fuse Pro 27.5+, Surly 1x1
Offroad motorcycles often have a little 'duckbill' on the rear fender like that. If its in the right place, it does a great job. However, if you aren't sure what the exact right place is, its easier to just put on a big one and take care of business. 
peace,
sam

peace,
sam
#15
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Originally Posted by MichaelW
Wahing up liquid bottles make good raw material. They have a built-in curve for structural ridgidity.
#16
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Originally Posted by vrkelley
Cool light weight idea. How did you make the fringe part? Will that go on the front tire also?
I just slashed the tire rubber, nothing fancy. The strips atre about a quarter inch wide, but nothing excessively neat.
And I put mine specifically on the front tire, that's where I needed it most.
#17
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After seeing several shapes, I'm trying to decide how to re-make that fender. Wish I had a slo-mo picture...As the front wheel rotates clockwise, the muck throws back toward the rider.
Mr. Sexy Fender's flap looks like mine.... hmmm https://www.bikeforums.net/commuting/52543-sexy-new-fenders.html
So how can a small flap that's attached on the fender work then?
Mr. Sexy Fender's flap looks like mine.... hmmm https://www.bikeforums.net/commuting/52543-sexy-new-fenders.html
So how can a small flap that's attached on the fender work then?
#18
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Originally Posted by vrkelley
Wow these are about 1/3 the length of the ones posted at the top of the thread.
Are REAR flaps actually necessary if the bike has a full fender**********? Seems like overkill.
Are REAR flaps actually necessary if the bike has a full fender**********? Seems like overkill.
The Planet Bike fenders are shorter than Esge (SKS) or Zéfal, so you would almost need to install a homemade mudflap under the Planet Bike mudflap.
As for the rear flap, it depends. I think it might be useful if you ride in close formation, especially in midst/slight rain/drizzel (sp.), which is typical of North-West U.S. (Where the author lives). In my case, it's essential because I often tow a Piccolo and used to tow a child trailer behind it.
#19
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Youch! I"m on the 3rd re-design of that mud flap.
1. Vinyl parachute with coat hanger...shifted in the sleeve I made for it...rubbed on tire.
2. 1 Liter soda bottle - would not curve small enough for a road style fender. When mounted on the outside of the fender, the edges had poor contact.
3. Old Michelin 23cm tire to fit as a mud flap. Worked the best at first but after 100 miles, started rubbing against the tire. There seemed to be no way to retain it's shape.
I'm going to add another screw hole and retry the home-made Michelin mud-flap.
1. Vinyl parachute with coat hanger...shifted in the sleeve I made for it...rubbed on tire.
2. 1 Liter soda bottle - would not curve small enough for a road style fender. When mounted on the outside of the fender, the edges had poor contact.
3. Old Michelin 23cm tire to fit as a mud flap. Worked the best at first but after 100 miles, started rubbing against the tire. There seemed to be no way to retain it's shape.
I'm going to add another screw hole and retry the home-made Michelin mud-flap.
#21
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Bikes: 1978 Fuji - now fixed and pegged. 1980s Cannondale Touring - pegged with 18 speeds. 2001 Cannondale CADD 3 - not being ridden
The stuff used for lawn signs works well. It's like cardboard, but stiff plastic. I used pop rivits to attach mine to the front fender and they work like a charm.
#22
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SchrieberBike,
Great...our primary election is this Tuesday...maybe I"ll get a cast-off (from a loosing candidate). Were you able to curve the sign into the road bike's fender then?
How well does it hold up in wind,+ rain?
Great...our primary election is this Tuesday...maybe I"ll get a cast-off (from a loosing candidate). Were you able to curve the sign into the road bike's fender then?
How well does it hold up in wind,+ rain?





