kando

I just bought a 62cm Surly long haul (disc) trucker.
It is spec'd with "Continental Contact, 700c x 37mm" tires.


I am looking into purchasing SKS longboard (bluemel) fenders.
These only come in 35mm and 45mm widths.


The rule of thumb is that fender width should be equal to tire width + 10mm.


Will the longboard fenders have too much sidespray with 45mm fenders,
as this is only 8mm greater than the tires?


Should I instead purchase 53mm standard bluemel fenders?

HardyWeinberg

The mudflap is where you really get the value from the longboard so I would stick w/ those. I don't think the extra 2mm of tire will mess you up measurably more.

ijsbrand

Black 45 mm wide long boards, with 37 mm tyres -- yes I often have to brush off the dried sand bits from the fenders some time after a ride in the rain. But it really works. It's my bad weather bike.

kando

As a follow up question, what are the odds that I would want to increase the width of the tire in the future?

(Odds that I'd want to shrink it?)

I'm from the northeast in the US (RI).
My goal is to start riding in the winter as well, in rain and otherwise;
37mm seems like a decent width for the region.

HardyWeinberg

I don't know but I have settled on 35 as my sweet spot for pudgy but not outright bulbous. My crosscheck has 2 sets of 35s, one w/ and one w/o studs for the direst winter stuff. 700x40 was too much for me.

mcours2006

I just bought a set of 35 mm fenders for my commute, which takes 32-35 mm tires. My bad. It was only after I received the fenders that it stated that for 35mm tires I should be using 45mm fenders.

I put them on the bike and it looks fine. It doesn't look any worse/better than MK2's I have on my road bike with 25mm tires, and that's a really tight fit.

So you ought to be fine.

bikeclub

Rivendell now has 55 mm width SKS fenders, I believe.

tsl

The 10mm-over-tire-width guideline is exactly that--only a guideline. It's something that works for many cyclists much of the time. There are no fender police.

It's been my experience that fender mounting is as important as fender width. The closer to the tire (within reason) the better. Mounted nice and straight over the tire is better than off-center or weaving back and forth.

Early on, I couldn't afford a second, wider, set of fenders for my 35mm studded snow tires. I ran the whole winter with my SKS P-35 35mm "summer" fenders. I was not arrested, no kittens were harmed, and the bike and I stayed about as clean and dry as you could expect during a Great Lakes winter. I could see no light between the tires and the fenders, and they were well centered and straight above the tires.

The following year, 45 mm Planet Bike Cascadias, hastily mounted, and what a mess.

So don't sweat two stinkin' mms. Do sweat the installation details. Take your time, do it right, and you'll have no problems.

Marc40a

I would definitely opt for longboards over standard length. A shorter fender will be messier than longer fender that's a couple mm narrow.

That said, I run longboard 45 mms on two bikes: one with 29mm tires, one with 38mms.

The bike with 29mm tires stays immaculately clean, whereas the bike with wider tires accumulates dirt and on the bottom bracket. Whether this is a function of bottom bracket height or the fender/tire ratio, I'm not sure. The dirty bike does have a lower BB.

Do your continentals measure the full 37 wide? That's really the cutoff point between 45 mm and 55 mm longboards. If you see yourself running big tires in the future go for the 55mm, if 37 is the max you'll use and you could see yourself trending towards narrower tires in the future, then go for the 45mm.

RubeRad

that you know of...

tarwheel 

Are the Continental Contacts truly 37 mm wide or just spec'd at that width? In my experience, Conti tires tend to run narrower than spec'd.

I've got 45 mm SKS Longboards on my Soma Saga, and they fit just fine with Clement LAS tires, which measure 36 mm wide on my wheels. I cut the front fender shorter because it was so long that it was dragging the ground in spots. Here's a photo.