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A friend of mine had a problem with his Ican rear wheel hub a few weeks ago. When he would coast, the hub would make a high-pitched whirring sound it shouldn’t. Now, there are six contact points in the Ican hub so it makes a distinct free-wheel sound when coasting. I happen to think it sounds awesome, personally. I have a set of the standard wheels on my rain bike – and they recently started making the same sound when free-wheeling. Now, it should be clear from “rain” bike that the Icans get the worst of the riding conditions. If there’s more than a 15% chance of rain I won’t take my good bike. The Trek, my rain bike, has been through a lot since I put those wheels on the bike a year or two ago. I’m happily surprised that they lasted this long without a servicing.
Now, when you pull the hub apart, if you want to go hole hog, you can pull the dust caps on the bearings and install new balls, but mine were nowhere near needing that yet. The hub did require a thorough cleaning, though.
This level of cleaning and servicing is so astoundingly easy, it’s almost not worthy of a post, but it will help some, and it’s an excellent start into bicycle maintenance that’s fairly difficult to do wrong. So let’s begin.
For tools, you’ll need the following:
A chain whip, cassette removal nut, a big wrench, two 5 mm Allen wrenches, heavy lube, light lube.
First, we remove the wheel and the cassette from the wheel. With the wheel standing upright, insert one 5 mm Allen wrench in either side of the axle hole (where the quick release runs through the axle) and loosen the dust cap (it threads into the cassette body). Once the dust cap nut is removed, the cassette body simply slides out of the hub, exposing the sealed bearings. Give the bearings a quick spin to make sure there’s no “grinding” feel to them. If so, the ball bearings will need to be replaced (at which point I march the wheel straight to the shop and pay them to deal with it). If the bearings are good, all that’s left is to clean everything, lube the moving pieces and put it back together.
I like to use a light spray lube on the pawls (the spring-loaded teeth that grab onto the hub when the pedals are turned). I find heavy and dry lubes tend to gum up the cassette body. So I hit each pawl (6 total for Ican standard wheels) with a quick blast of the light lube. This will clean and lube the inner working surfaces. Wipe off the excess. Then I’ll turn my attention to the inner teeth of the hub. I wipe the surfaces clean with a paper towel being sure not to press any dirt into the bearing cover plate. Heavy lube goes on the bearing surfaces that the axle goes through.
Once that’s done we’re going to install the cassette body back onto the axle. Now, this gets a little tricky because there’s a floating washer inside the cassette body, behind the bearing, that can get in the way and make it seem like the body won’t slide back onto the axle. Center that washer with your pinky finger, a q-tip, or a piece of wire/cable and slide the cassette body over the axle. With the body on the axle, it’ll stop shy of entering the hub body because the pawls are sticking out. Finagle them into position so the cassette body fully seats in the hub.
NOW, before you go and put the dust cap back on, give the cassette body a little spin to make sure it operates smoothly as it sits. If there’s some resistance to it, it’s likely not seated properly. Remove the cassette body and reinsert it. Now you can thread on the dust cap and tighten it down. Put the cassette back on, tighten it down and Bob’s your uncle.
Give it a quick test-spin to make sure the funky whirring sound is gone.
With the proper tools handy, this should take ten or fifteen minutes – and it’s worth it to keep your rear wheel running smoothly. Especially if you’re riding the bike in gnarly conditions.
To be clear, there are a few levels of “had it” when we are talking about headsets.
We have everything from “completely pooched” to “clean it, lube it and put it back together”.
I’ve had the range.
So let’s get into this. A quill stem, threaded headset will act a little differently from a threadless setup when it goes bad. Know this right off the bat. Typical enemies of the headset are wet weather, the dreaded turbo (indoor) trainer – especially if you use a trainer thong that covers the headset/stem and leave it there after you’re done riding. All of that salt and sweat gets sucked right into the fork and bearings. If you’ve read more than one or two posts, you know how meticulous I am about maintaining my bikes. This is my fork after a few years on the trainer without taking the headset apart to clean everything up… you know what, it’s too gross. I’m not going to post it. It’s terrible. There was rust and salty crust everywhere. And the funny thing is, Chris King components are so good, the headset wasn’t acting up in any way whatsoever.
Now, had I left that go a little longer, the bearings would have worn out. Once the bearings start going you’ll feel a catch in the steering. Shortly after that you’ll notice some play in the headset. You’ll try to tighten it up to take the play out but when you tighten it up the “catch” worsens. It’s at this point the lack of maintenance will start causing “speed wobbles”. Bombing down a hill at 40+ mph, the bike will start to shimmy and it will scare the ever-loving $#!+ out of you. Well, sparky, it’s time for a new headset if you’re still alive.
Point is, and I should know better by now, clean the headset whether it needs it or not once a year. Two or three (or more) times if you’re riding in wet or dusty conditions. And if you’re leaving your bike on the trainer, take your sweaty stuff off the headset after your ride. You don’t want to see what sweat does to aluminum races on a full carbon fork.
That’s a worse case scenario, though. What about something a little less “terrible”?
It just so happens, my Venge was in need of some service… yesterday. This bike sees zero trainer time, rare, if ever, dusty conditions, or even rain. It’s been through just a few light rains that I got caught out in, one damp morning on DALMAC that was fairly epic during a 100-miler and one three minute downpour when the rain hit me on the final mile sprint to my house trying to beat it… in the seven years I’ve owned the bike. I still clean and lube the headset at the end of a season whether it needs it or not.
So I’d just recently (the day before yesterday) developed this weird knock when I went over a fairly large bump or crack in the asphalt. It sounded like it was the sealed cartridge bearing clunking in the frame. I could have tightened everything up and made it go away, but I could have done some damage over time (press fit headset bearings aren’t exactly cheap – nor is a cracked frame from overtightening the bearings to get rid of a clunk). There was no “play” in the headset, either. I could be going 30-mph and hit the brakes and it’d slow down just like it should. The old “brake and rock” technique to check to make sure the headset is tight? Just as it should be. The light coating of lube had simply worn out.
That evening I pulled everything apart, cleaned everything meticulously, checked the bearings (they operated perfectly, as good as new, no slop, no binding points or catches). I lubed the bearings and put it back together and took it for a test ride. And just like that, twenty minutes is all it took, my bike is back to normal and quiet again.
To put a bow on this post, maintaining the headset is just as important as the bottom bracket bearings. If you don’t know what you’re doing, the boys on GCN have video guides to help you or you can take your bike to the local shop if you’re not mechanically inclined. The headset is what allows the bike to steer. It should be tended to at least once a year – more if you ride in conditions that warrant it. The last thing you want failing catastrophically when you’re bombing down a hill at top speed is the steering. Catastrophic is the right word. If it needs special care, as mine did, your bike will tell you what it needs if you know what you’re listening for. If you don’t, when your bike starts making weird clunks or noises, that’s bad. They should be quiet when properly maintained. Even old bikes. Take it to the shop and let them sort it out.