Gravelbike Mudguards Question – Tyre Clearance etc

Now I’ve got a dedicated road bike I’m setting up my Genesis CDA for winter road duties (to save my shiny new one) as well as gravel.  To this end I want to fit some mudguards and some slightly narrower tyres.  It currently has 42mm Conti Tyres on which are nice and comfortable off road, but probably overkill for what I need.

My thinking is to drop the tyre size down to 35mm and get some Gravel King SKs which appear to do well on and off road.  With this in ming what size guards should I be looking for – ones to suit a 35mm tyre or go larger (if possible) for flexibility on the tyre size?

Also what guards should I be looking at?

Thanks

Can’t help with the guards (i’ve got the same dilemma myself), but the Gravekings SKs come up wide, the 35’s I have are more like 38.

I’ve had several goes at this on a couple of bikes before managing to maximise the clearance. A couple of tips:

– Guards all have different profile shapes as well as different widths: Bluemels guards tend to have a rounder profile, Chromoplastics tend to have a squarer one, while some others (eg Cloudbursts) have different profiles still. The most difficult clearance point on a gravel bike will almost certainly be the fork crown, so check the shape of that first.

– You may find that chainstay bridge clearance is tight; if so you can often use a reflector bracket to fix the guard just above the bridge.

– If you’re riding off-road you may have a problem with back end of the front guard swaying and catching the tyre. (Especially so on one of my bikes where I’ve mounted the stays to lowrider bosses instead of near the dropouts.) It can help to reposition the lower stay and perhaps even cut the guard shorter, if you value off-roadability over dry feet. Some guards have positionable stays, but it’s easy to drill out the rivets on SKS guards and reposition them if need be (although it leaves you with two holes: you can either cover them with tape or use them to affix a flap).

– Off-roading will also take its toll on less sturdy attachment points at the guard end of the stays, though TBH on 700c guards I’ve not seen many really weak points here; for some reason it’s normally only an issue on 26″ and smaller sizes.

Overall, though, I’ve been pleasantly surprised with how well mudguards fare off-road, both in terms of coping with mud and (provided you deal with any issues with the front guard) staying put of the rougher stuff. But it does take more patience than a road/touring bike, and occasionally the purchase of multiple guards, if you want to really maximise clearance while keeping everything sufficiently stiff off-road. All bikes are different: good luck 😉

I’ve got the bluemels guards and 35c GK SKs but haven’t fitted them together yet – I’ll have a look at the clearance tonight and report.

SKS on my Salsa Vaya with 650b byways but the guards come in different widths, they can be fiddly to fit but I’d go for a width 1-2 mm wider than the actual tyre width. They look great once fitted correctly

Thanks so far all, especially Bez for such a detailed response.

jommoe – I’m interested to hear how that goes.

fudge – what size and model are the SKS?

I use 45mm guards with 28mm tyres on my bike. Plenty of clearance, and I can run 32mm studded tyres when it is icy without messing about with the guards.

I’d just fit the widest round section SKS or Bluemel guards you can.

I just fitted some SKS Bluemels (42mm) to the Vagabond.  Seem pretty sturdy and quiet but have not used in anger.  Pictured with 35c Landcruisers there is just enough clearance.

razorrazoo

if you need some cheap new unused guards, drop me a pm.  I have some that will take a 42mm tyre.

ive got 42c nanos on my rove Al with wide PDW full metal fenders.

no sway no rubbing no rattling or squeeking

the worst issue i have is that the rubber *flap* sometimes contacts the ground on steep steps /roots and gets folded into the tire- if i was doing alot more of that i might take it off , as is i just use it for gravel tracks and a lap of the woods on the way home.

trail_rat whatabout some leather or PU leather mudflaps?  I’m still deciding 😋

Stupid question, but how do I work out what size (width) guards will fit?

Make some rough measurements with whatever you can and then add some guesswork. If you currently have 42s and you’re not too tight on clearance with those, you might be able to fit 45s. Or you might not. And again, note that not all 45s are equal: the Chromoplastic 45s I have on my Crossrip are also sculpted around the crown area, which just happens to work on that fork but was problematic on another one. Sadly it’s a bit of a minefield if you want to get the most out of limited clearance.

I have the 53mm Bluemels on my Amazon with 47mm WTB Byways

not sure it matters what the flaps made of malvern rider

the issue is that when it folds up its continuously pushed up by the rotation of teh wheel.

Rubber flaps suck, though—literally. They’re unnecessarily heavy and IME that contributes to their propensity to get pulled up by the tyre—it’s an issue I’ve never had with lighter flaps (though I tended to have it from the flaps’ weight causing them to move around, rather than specifically getting caught on the ground).

I use Raw Flaps (ouch) these days and haven’t had a flap-sucking problem yet. But I suspect a good alternative is supermarket packets of ham (at least, Waitrose ones anyway); it’s light but reasonably stiff, and since they’re made of black plastic which can’t be recycled it’s a noble endeavour to make mudflaps out of them 🙂

Got these:-

http://freshtripe.co.uk/velo-orange-45mm-hammered-mudguards-700c/

A fiddle to fit for the first time but solid as a rock. Best guards I’ve owned and I’ve owned a lot!

Paired with schwalbe g-one all round 35mm.

I’d be taking the guards off if doing anything more than a short bit of fire road to join up a road ride though. Not got the clearance to handle much without clagging up.

fair comment trail-rat.  Assuming it’s the front flap giving probs, then I’d agree that leaving it off is prob for the best.

Have been looking at the SKS Spoiler Pro for the rear, but smallest I can find is 45mm.  May just grab one and see how it goes/hack it.

Raw Flaps FTW

trail_rat

not sure it matters what the flaps made of malvern rider

the issue is that when it folds up its continuously pushed up by the rotation of the wheel.

And nothing needs to touch them to cause this to happen, as I discovered one windy day when my mudflaps got blown against the rear tyre and then dragged/wedged up into the gap. Nearly as good as a disk brake. 🙂

Just glad it wasn’t the front.

Which brings up another point. On a gravel bike which is far more likely to pick up stray bits of wood etc, it’s wise to make sure your mudguards have breakaway stays.

Does an effective mudhugger style option exist?

I have mudhuggers on my plus bike and think it would be overkill on the 2.1 x 29 on the Vagabond but don’t think conventional guards will have sufficient clearance.

thanks

jaminb I was asking that sort of question a while back, someone suggested that the largest Bluemels would possibly clear 2.1 Nanos.   I decided against it as the Gods of toe overlap were rumbling about something or other…

https://singletrackworld.com/forum/topic/what-tyres-mudguard-clearance-for-42mm-sks-bluemels/

The rear shouldn’t be a problem with full wide guard as long as you’re either not running a front mech or willing to cut Dremel some of the guard out to clear it?

I can fit 2.0″ WTB Nine Lines under the 53mm Bluemels in the picture above. I have some 65mm Chromoplastics on my commuter and they’re huge.

When it comes to things with knobs on, IME the limiting factor on SKS/Bluemels guards tends to be the bridges where the stays meet the guard. Maybe you can bend them out a bit, but I suspect they’re not beefy enough to overcome the shape of the guard itself.

I’ve just got from Chromiplastics to the Bontrager NCS. Whilst the struts look a bit untidy compared to some of the options above, they are a piece of piss to fit and adjust and have stayed in place on some bumpy stuff to date.

These are the SKS guards I fitted to my daughter’s gravel bike.

I split them at the seatstay bridge, and made them quickly detachable with wingnuts.

SKS guards are supposed to be at least 5mm wider than the tyre they cover – i.e. P50 (50mm) Chromoplastics have a quoted capacity of 45mm tyres. I’ve found leeway in that. I run 50mm Chromoplastics with 47m Smart Sams or Specialized Triggers – they only just cover the tyre but they do collect all the muck from mucky off-road/light trail centre use. There’s a bit of movement and noise over rougher sections as the stays contact the side of the tyre, but in 5+ years and 000’s miles that’s never been an issue. That’s with the front guard lower stays attaching to plastic P-clips around the fork legs due to lack of eyelets on the fork – I’m sure with proper threaded eyelets they’d be more secure.

My experience with 65mm SKS Blumels was I found them less sturdy than the Chromoplastics. Much less rigidity and more contact with the tyre on rougher ground.

Mine recently got totalled in a car/bike interaction though so I’m going to look around at alternatives before inevitably buying a new set of 50mm Chromoplastics.

And on flaps, I’ve never once had an issue with the rubber SKS flap on mine. Apart from losing the first one after vibrations loosened the nut/bolt.

had a quick check – 45mm SKS bluemels and 35(really 37)c Gravelkings = plenty of clearance. It’ll depend on your frame to a degree though.

I’ve previously used the narrower chromoplastics and found that they fail first at the brackets attaching stay to guard but generally they are robust enough for lumpy roads and gravelling

Thanks jommoe, that’s useful to know.

45mm Bluemels ordered, at £25 worth a punt.  Now to source some tyres…..

Bluemels are good. Got some 45 Mum ones which just fit over my 38 Schwalbe g ones. Left the rear stay a little long to push the rear section away to make it easier to swap the wheel over for turbo duties.