Mud build up on rear guard - M6R

[Time Waster]

I'm about 9 months ownership of a brompton for commuting by train. The industrial estate I work on is muddy with a very gritty mud at that. I recently realised that the rubbing noise is simply mud between tyre and guard. As in completely filling the gap in most of the guard length. I cleaned it out after realising it was clogged but next morning it picked up almost as much mud in just one way journey into work.

The attachment at the back of the rack came undone and I lost the nut. Fixed that and cleaned guard out until it stopped rubbing.

Gap is big at the front edge of the rear guard but less so over most of the guards length.

What can I do to stop the mud build up? Is it something to do with the setup? Is it because the OE guard isn't that good? The bike is stock except for an Eerder bumper bracket on the trail edge of the front guard to protect it as I broke the first guard in a rookie way
The new front guard is brompton spec.

Any ideas?

 

[rogerzilla]

They get pretty close to the tyre at one point. I think you're just exceeding its design parameters. It says something about tarmac and well-made paths in the manual.

 

[oldwheels]

I found that problem with mud as well because I tended to go off road in places where a Brompton was not designed to go.
I just had to stop and clear it out as soon as the build up started to rub.

 

[u_i]

I ran into the problem myself when riding over muddy farm roads. When space is tight and one wants to move the fender farther away on front wheels of the regular bikes, one may cut the fender at the fork crown and add a stay. The solution might be too complicated to bother, but principally one could think about something like that for the Brompton rear wheel with rack.

 

[berlinonaut]

There is a reason why MTBs don't have mudguards despite they are designed to be ridden in massive mud... So if you want to get rid of the issue get rid of the mudguards (which has obvious downsides under normal conditions). Usually one wants the mudguards to be close to the tires to deliver the best protection - unfortunately this only works with water and other loose things.

 

[roley poley]

Often have to stop and poke the rear mudguard clear with a thin stick..that or a slow ride through a puddle to rinse and dilute the block

 

[a.twiddler]

I'm about 9 months ownership of a brompton for commuting by train. The industrial estate I work on is muddy with a very gritty mud at that. I recently realised that the rubbing noise is simply mud between tyre and guard. As in completely filling the gap in most of the guard length. I cleaned it out after realising it was clogged but next morning it picked up almost as much mud in just one way journey into work.

The attachment at the back of the rack came undone and I lost the nut. Fixed that and cleaned guard out until it stopped rubbing.

Gap is big at the front edge of the rear guard but less so over most of the guards length.

What can I do to stop the mud build up? Is it something to do with the setup? Is it because the OE guard isn't that good? The bike is stock except for an Eerder bumper bracket on the trail edge of the front guard to protect it as I broke the first guard in a rookie way
The new front guard is brompton spec.

Any ideas?

Just been out to have a peer at mine which has a rack. If your mudguard is close to the rack there probably isn't much scope for increasing the clearance without somehow raising the rack which might have a secondary effect on the fold, even if you only raise it by a few mm. You will only find out if you try it. Certainly while experimenting with bar ends on mine I found that a small amount of adjustment caused interference with the ground or back tyre while folded.

Thinking in a different direction, I used to use a thing called a tyre saver, also known as a flint catcher or thorn catcher in the days before puncture resistant tyres were available. Available on ebay under l'eroica or vintage. They would normally fit to a brake bolt and rest on the tyre so that any flints or thorns that stuck to the tyre would get flicked off before they had a chance to penetrate. I had variable degrees of success with these but a secondary effect was that they tended to keep the tyre clean by skimming off any mud or grit that it might collect. Depending on how muddy your tyres get, one of these might help.

On my Brompton the rear mudflap is held on by a bolt as I had to fit a replacement. Possibly ones in original condition will have a rivet holding the mudflap on. This would seem to be a good place to fit a tyre saver, pointing down and resting on the tyre to intercept any mud before it enters the mudguard. It might even help in puncture prevention. You could even make one with plastic tube and wire.

A simple idea, but might help reduce your mud clogging.