Wednesday, March 27, 2013

SKS RaceBlade Long and 650c wheels: Mission Impossible?

UPDATE early 2016: SKS have updated the retaining clip design (good), but fundamentally the stays and mounts are the same. So there's no reason to think this hack wouldn't work on the 2016 model. Here's my in-depth review of the new model:

As a low-cost foray into road cycling my wife recently purchased a B'twin Triban 3 roadbike from Decathlon - a huge French sports retailer. These £299 carbon-forked aluminium roadbikes with Shimano Sora/2300 components are highly rated as winter trainer or commuter bikes, as they cost not much and do pretty much what you need. Reviews are unanimously positive - no, this isn't a full-carbon Ultegra + Zipp 303 rocketship, but then again it cost less than one shifter or wheel on a posh racer.

It always was our intention to put mudguards on, and the SKS RaceBlade Long was the guard of choice - easily removable, light, robust and good-looking, and can be fitted to bikes without mudguard mounts too, using the quick-release skewer to hold them in place. Reviews are pretty positive too. So £44.95 later the box arrived, and all looked good.

(If you are already convinced, please click here to buy from Wiggle. I get 4% to spend on cheese, bikeparts and beer, the rest foolishly)

Now the accepted wisdom of fitting SKS guards seems to be:

1. Read instructions
2. Read instructions again
3. Discard instructions, make large mug of Yorkshire* tea
5. Get On With It

and I fully concur. So off we go Trev...

...except we ran into a *minor* snag. You see, unbeknownst to us, and certainly not mentioned anywhere on the Decathlon website is the fact that apparently frame sizes below 54cm come with 650c wheels, smaller than the standard 700c ones SKS make the RaceBlade Long to fit. A perfectly acceptable thing to do, as 700c wheels on tiny frames is just silly. It would have been nice to know, however, to ensure spare tyres and tubes were to hand. At this point it was a good thing the children were in bed, as there was some colourful language used.

A quick Google confirmed that apparently no-one on earth makes removable 650c mudguards. So in true No. 8 wire spirit, and with much spousal scepticisim, the Fettling began.

What was obvious was that the stainless steel stays were far too long. No amount of bodging was going to change this fact, so they had to be cut down in a way that didn't compromise the rigidity of the guard or profile against the tyre. Knowing that Mrs GâteauVélo would be insufferable if this lack of Fettliness was allowed to stand, a plan was hatched...

Measure, measure and measure again

 As every bike's mudguard mount location and fork rake differ, there is no perfect calculation to make here. So you have to measure up against the guard on your bike, to get the correct length to cut the mudguard stays to.

Step 1: Leave the stays off the mudguard, and fix the whole setup to the bike as per instructions. Make sure the stays are slid all the way down inside the black plastic endcaps that attach to the quick-release tabs - there is a small Allen screw that locks them in place, so loosen it first to make sure the stays are all the way in. Here you can see the depth of the stay inside the endcap.  Make sure you have the maximum inserted.

Attach the under-brake mounts and get them all lined up nicely, clipping the mudguard into the under-brake mount. Basically what you have done is fitted the mudguard, but not slipped the stays over it so it can flop against the tyre.

Step 2: Lift the mudguard off the tyre to the desired clearance. Stuff some rags in between, folded over to give the right thickness.

Step 3: Take a caliper or ruler, and measure the gap between the top of the mudguard and the BOTTOM of the black plastic stay bridge. This gives you the distance the stays need to shorten by to correctly space the guard from the tyre. In this case, 55mm.

Step 4: Remove the steel stays from their plastic endcaps, and measure along them by the required distance - in our case 55mm. Note this needs doing in two parts as the stay is bent - if you measure direct from the tip you are 'cutting the corner' and will be cutting it too short, which is very bad. I cannot emphasise enough getting this right - if you cut too short then you have just ruined £45 worth of mudguards. Use a pair of pliers to mark the point.

Choppy Choppy

Step 5: NOTE: do this step for just one side of one stay first. Take deep breath and cut the stay. As this is very high quality stainless steel, normal pliers probably won't do the job - use either a high TPI hacksaw or a set of specific cutters (these ones date from 1948, bah gum).

Step 6: Using a vice, get an un-cut stay as a guide and bend the newly-cut one to match, in the same direction it will need to sit into the endcap. Do not try to bend it in the endcap - they are not strong plastic and the force needed to bend is considerable.

Step 7: Take your newly-cut-down stay and slide it onto the mudguard, into the correct position, 1/3 of the distance between brake and rear. Re-insert it into the plastic endcap. Check your handiwork (leave the other side out of the plastic cap for now). If there is a God in Heaven your mudguard should now be correctly spaced from the tyre, with some adjustment room left in the endcap if needed. If correct, now measure and cut the other side of the stay the same length. If you have measured correctly but need a bit less clearance, just cut down the stay a few more mm or whatever. If you have cut the stay too short and there isn't enough adjustment in the plastic endcap to hold it securely, re-read Steps 2-5, collect credit card and off to eBay with you. Do not pass Wife.

Step 8: If all is good with the 'top' stay closest to the brake, now repeat process for the 'bottom' stay furthest away.

Step 9. Make another mug of Yorkshire tea. Do all over again for front wheel.

And Voilå! You now have a rock-solid set of removable guards on a 650c wheelset. These guards are easily strong enough to pick the bike up with, don't rub at all even under heavy pedaling/cornering, and unclip / refit in a few seconds each. A bonus in putting a 700c guard on a 650c wheel is that the guard extends even lower down the back of the wheel, offering even more protection from water/crud.

With guards removed - not too shabby.

If you want to buy a set of Raceblade Long guards, your LBS should be able to oblige. If you intend to purchase online, please click here to go to Wiggle's online store - I'll get a whopping 4% of your purchase, and this will of course be spent wisely on beer, cheese and bike parts.

* don't ask me why it has to be Yorkshire tea. Just trust me. Any subsequent tendency to suck your teeth, say 'eee lad' or stroke a whippet is entirely a personal issue.