20" aluminium mudguards

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cycle tramp
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Re: 20" aluminium mudguards

Postby cycle tramp » 18 Feb 2019, 6:03pm

NATURAL ANKLING wrote:Hi,
All looks a bit of a mess, I would think about making the rear mudguard in two parts.
Joining Either side of the rear brake.
Make a U shaped bracket to fix on the brake Boss, Over or under the brake, fix mudguards to either end of bracket.
Aluminium or stainless I think will be even more prone to cracking.
I know you want silver so going to a PVC type mudguard (black?) Would not be ideal but you wouldn’t get any more cracked mudguards.
Modifying the frames are little bit drastic, for now just make a two-part fabricated rear gaurd.

Front mudguard needs more stays as said.


Sounds like a good idea.... I note with some interest that several single speed cyclists have taken to using the front mudguards as the rear. The mudguards is mounted in the usual way, but a support has been added to the front nose of the mudguards which then attaches to the rear brake bridge..... there doesn't appear to be any notes with the photographs so I'm guessing the idea was either a Great success or dismal failure....
...interested in hearing about and seeing your solutions

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NATURAL ANKLING
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Re: 20" aluminium mudguards

Postby NATURAL ANKLING » 19 Feb 2019, 10:07am

Hi,
Just an idea I envisage, not got a Moulton, no reason why it wouldn’t work.
Just some careful thought on what the bracket would look like and what material To use.
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Mick F
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Re: 20" aluminium mudguards

Postby Mick F » 19 Feb 2019, 11:56am

20miles done sans mudguards.
Absolutely wonderful! :D :D

Silence.
No drumming, swishing, rattling.
I don't know why I haven't tried this before!


As soon as I got home, I turned the bike upside down, and then I saw the bits I'd missed when washing it yesterday. The BB and chainstays fwd of the bridge were caked in fine dry mud. I suppose this comes from the front wheel as the front mudguard is of inadequate design. I probably needs to be lower and have a big mudflap.

After lunch, I'll have a fettle with the fit of the rear mudguard. I'll consider cutting and brackets etc. Nothing to lose by creating a prototype as I'll be buying new ones be they alu or plastic eventually.
Mick F. Cornwall

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Mick F
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Re: 20" aluminium mudguards

Postby Mick F » 19 Feb 2019, 1:47pm

Had a fiddle.
Not good news.

The suggestion of Brucey's to move the bottom front rearwards (even at the expense of easy wheel removal) sounds good. The idea is to make the mudguard curve correctly.

Yes, it works, but in order to do it, the bottom/front needs to move rearwards over an inch - possibly an inch and a half. Anything less does nothing. Moving it that far precludes the wheel even fitting at all. With the wheel in place, the mudguard will only move three-quarters of an inch - maybe a tad further - but nowhere near enough at all. Basically, the idea doesn't work in practice. Sadly. :cry:

As for cutting and bracketing the mudguard to get over the fact that the brake bridge is too low, I'm going to sleep on this but it has merit. In fact it's the only solution.

Meanwhile, I'm leaving the mudguards off.
Mick F. Cornwall

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Re: 20" aluminium mudguards

Postby PDQ Mobile » 19 Feb 2019, 1:54pm

Mick F wrote:Had a fiddle.
Not good news.

The suggestion of Brucey's to move the bottom front rearwards (even at the expense of easy wheel removal) sounds good. The idea is to make the mudguard curve correctly.

Yes, it works, but in order to do it, the bottom/front needs to move rearwards over an inch - possibly an inch and a half. Anything less does nothing. Moving it that far precludes the wheel even fitting at all. With the wheel in place, the mudguard will only move three-quarters of an inch - maybe a tad further - but nowhere near enough at all. Basically, the idea doesn't work in practice. Sadly. :cry:

As for cutting and bracketing the mudguard to get over the fact that the brake bridge is too low, I'm going to sleep on this but it has merit. In fact it's the only solution.

Meanwhile, I'm leaving the mudguards off.

How much was that frame? :shock:

Just a thought, but could you cut the mudguard between the bridges somewhere(or at the brake bridge?) and then use a spacer at the join.
Might have to be shorter at the back?

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Re: 20" aluminium mudguards

Postby Brucey » 19 Feb 2019, 1:55pm

re silence; I really don't like riding with a rack on my most-used bike. The transmission on that bike is virtually silent (IGH with nice chain and no tensioner of course) which means that I can very often hear the rack; it resonates with normal vibrations from the road, and I can hear the wind swooshing over it too. FWIW I don't hear these things so clearly on my touring bike, (with a dedangler transmission, which is a lot noisier).

I have often thought about making a rack in aero-profile tubing with foam filling in it; I am sure it would be quieter. Not that I recommend that you do this but the aero drag of a normal rack is not insubstantial; if you carry one in your hand at normal speeds (look out for the spokes....) it is clearly quite a draggy thing.

FWIW if your mudguard doesn't fit properly now, it may well have taken a bit of a partial set in the weird shape in which it was installed. If so, hot air gun time.... FWIW I have installed mudguards successfully on several moultons using better spacers, thus undoing the terrible work of a local moulton dealer..... :roll:

cheers
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Mick F
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Re: 20" aluminium mudguards

Postby Mick F » 19 Feb 2019, 3:31pm

PDQ Mobile wrote:How much was that frame? :shock:
Two grand for the whole bike .................. of which I have changed much of the componentry.
CF seatpost swapped for shiny alu.
Outer chainring 57t swapped for a 61t.
Rear mech was Tiagra but the top pivot wore out very quickly so now have a Shimano Deore XT Shadow.
STI Tiagra swapped for Dura Ace indexed DT shifters plus Tektro brake levers.
Tektro brake callipers swapped for Shimano 105.
Black handlebars swapped for a better shaped shiny alu ones.
Adjustable stem swapped for a fixed one. (still have the adjustable one in the shed)
Awful saddle swapped for a nice Brooks.
Black rims swapped for shiny alu.
3sp SA fitted.
SP hub dynamo fitted.

All decent redundant parts sold.

If I had to live my recent life again, I wouldn't have bought a complete bike but built up a frame with knowledge and hindsight, plus had the design of the rear triangle modified during manufacture.
Mick F. Cornwall

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Re: 20" aluminium mudguards

Postby Vorpal » 19 Feb 2019, 3:35pm

Brucey wrote:re silence; I really don't like riding with a rack on my most-used bike. The transmission on that bike is virtually silent (IGH with nice chain and no tensioner of course) which means that I can very often hear the rack; it resonates with normal vibrations from the road, and I can hear the wind swooshing over it too. FWIW I don't hear these things so clearly on my touring bike, (with a dedangler transmission, which is a lot noisier).

Or you could ride on studded tyres... :wink:
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― Nelson Mandela, Long Walk to Freedom

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Mick F
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Re: 20" aluminium mudguards

Postby Mick F » 19 Feb 2019, 3:38pm

Brucey wrote:FWIW if your mudguard doesn't fit properly now, it may well have taken a bit of a partial set in the weird shape in which it was installed. If so, hot air gun time.... FWIW I have installed mudguards successfully on several moultons using better spacers, thus undoing the terrible work of a local moulton dealer..... :roll:
Could be right there.

I wonder if the mathematics could show that it's impossible to get a regular curve to follow a 406/28 tyre using the chainstay bridge, the brake bridge and the two pairs of stays.

In order to do it, the curve would have to be non-regular.

Just a thought.
Mick F. Cornwall

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Mick F
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Re: 20" aluminium mudguards

Postby Mick F » 19 Feb 2019, 4:00pm

Mick F wrote:
Brucey wrote:FWIW if your mudguard doesn't fit properly now, it may well have taken a bit of a partial set in the weird shape in which it was installed. If so, hot air gun time.... FWIW I have installed mudguards successfully on several moultons using better spacers, thus undoing the terrible work of a local moulton dealer..... :roll:
Could be right there.

I wonder if the mathematics could show that it's impossible to get a regular curve to follow a 406/28 tyre using the chainstay bridge, the brake bridge and the two pairs of stays.

In order to do it, the curve would have to be non-regular.

Just a thought.
Still thinking.
Maybe I'm wrong. Maybe I damaged the mudguards when I painted them, especially the rear one. Also, looking at photos of the bike when it was new, you can see the mudguard fitting properly. And, if you zoom in, you can see a spacer! I'd forgotten all about that and probably removed it to allow for better wheel fitting and removal.
2016-03-03 08.59.23.jpg
2016-03-03 08.59.23.jpg
Mick F. Cornwall

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Re: 20" aluminium mudguards

Postby Brucey » 19 Feb 2019, 5:43pm

probably you didn't have the axle in the back of the dropouts before either; that can make a good mudguard fit virtually impossible.

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Mick F
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Re: 20" aluminium mudguards

Postby Mick F » 19 Feb 2019, 7:31pm

Brucey wrote:probably you didn't have the axle in the back of the dropouts before either; that can make a good mudguard fit virtually impossible.

cheers
Wrong.
The wheel has always gone back all the way. These days though, it goes back a little less.

I fitted a 61t ring and needed a longer chain. No problem using two quick links and a couple of extra links.
Then, I decided to turn the non-turn washers the other way round to make the wheel closer. That way, I could use two quick links and only one extra link.

The bike came with 116 links and I extended it to 120 links to allow big/big with a 61t. Droopy chain in small/small though.
By turning the non-turn washers 180deg so the lug was rearwards instead of forwards, it moved the wheel forwards so I could reduce the chain to 118 links.
This still allowed big/big, and also small/small wasn't having a droopy chain.
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Re: 20" aluminium mudguards

Postby Mick F » 20 Feb 2019, 2:35pm

I've bitten the bullet and removed the stays, bridges, nuts and bolts, securing clips, and the front mudflap.
All that is left are two arcs of plastic.

Looking at the rear one unconstrained by stays etc, the shape is all distorted. Not just non-regular curved, but distorted width-wize and is canted and cambered off from the straight and narrow.
Why?
I reckon that it's because I painted them.

Because the front one had cracked some time back, I'd repaired it with Araldite and an extra pair of stays. On inspection, I saw that Araldite was peeling away and the stay bridge was coming loose.

Both are only fit for the bin.
Mick F. Cornwall

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NATURAL ANKLING
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Re: 20" aluminium mudguards

Postby NATURAL ANKLING » 20 Feb 2019, 3:10pm

Hi,
Idea :idea:

Fit a short length of guard under brake bridge.
Attach cut down guards either side of bridge on to the short guard, use number plate screws, they don't rust, self locking nuts, file head down to reduce height, nut upper most, space apart with nuts.
Easy.
Priority Is Still 500K In 24..Just Dreaming...Stay Focused Guys And Keep Sharp...
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Re: 20" aluminium mudguards

Postby Brucey » 20 Feb 2019, 3:27pm

I think the rear mudguard went out of shape because it was fitted whilst strained into a weird shape. A useful axiom for mudguard fitment is that if any one fastening is undone and the mudguard moves appreciably, the mudguard must be being strained out of shape. If the mudguard curvature is correct and accurate it ought to be possible to achieve a good fit without such straining.

I think aradite peeling from plastic mudguards is more or less inevitable; it isn't the right adhesive for bonding to plastics of that sort.

cheers
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