When you work in the bicycle media, you see press releases and bulletins from around the world every day. Most of the time the news is comprised of interesting product developments, race results, efforts to grow cycling, and other fun bicycle stories. Unfortunately, you also see cycling accident reports — some that resulted in serious injury or worse.
Two recent incidents caught my attention. In both cases, the forks broke, causing the cyclists to crash and get badly hurt. Having broken forks while riding, I can say from experience that it’s one of the worst crashes you can have. I was extremely lucky to have it happen at slow speeds. Still, I hit the deck so fast and awkwardly, that I never had a chance to even try to roll to protect myself.
Breaking a fork is nothing you want to experience, so I’d like to offer some tips to check your tiller and hopefully prevent it from ever happening to you. These tips are for road bikes with threadless forks/headsets, which have become the standard setup. Threadless front ends are pretty easy to work on and usually only require common metric Allen wrenches you probably already have.
If you’re riding a newer road bike in excellent condition, and haven’t logged too many miles, it’s unlikely you need to worry about your front end. But hang onto this article for a year or so, after you’ve put in a season’s worth of miles, and then it might be time to check your fork.
Tip: If you ride your road bicycle regularly, you should remove the fork at least yearly to inspect it and the headset for wear and tear (the headset is the steering mechanism). If everything looks good inside, it’s a relatively easy job to clean the headset cups and bearings, add fresh grease and reassemble it all. Have a pro mechanic do it for you if you prefer. It’s not an expensive repair in most cases.
A fast way to tell that something’s not right with a fork is to check it for looseness in the frame. Forks are for steering, and they should turn smoothly without any front-to-back or side-to-side play or rattles when you ride over a pavement seam or bumps. (Forks sometimes become tighter, resulting in stiff steering, but it’s rare with threadless models.)
If you feel looseness or hear rattles, check for play by standing to the side of the bike’s front end. Grip the fork blades with your dominant hand and the down tube of the bike with your other hand. Then push and pull to feel if there’s a knocking feeling/sound from play in the headset.
Another way to test for this is to lift the front end of the bike about six inches off the ground and let it drop. If the headset is loose you’ll hear a rattle or clunk indicating the headset needs tightening.
Tips: If you get a rattle when you do the drop test but the headset is not loose, check the front wheel to ensure it’s tightly fastened. Also hold it at 12 o’clock and wiggle laterally to feel for play in the wheel’s hub bearings. Loose wheel bearings will cause a rattle, too. The other possibility is that the brake levers are rattling (that’s not a problem, just something many shifting brake levers do over bumps).
Adjusting the headset
Headsets can loosen up and it won’t damage or weaken the fork. But you should fine-tune the headset adjustment to eliminate the play or it could cause a problem over time.
This is usually as easy as loosening the stem bolts and tightening the allen bolt in the center of the top cap. This compresses the headset parts and removes the play. Use the headset tests to make sure that the fork turns smoothly and there’s no play. Then center the stem over the front wheel and tighten the stem bolts and you’ll be good to go.
Checking a headset that won’t adjust
If you find that you can’t remove the play in the headset, that’s a red flag that something more serious may be wrong. And, there are quite a few possibilities, from the compression fitting in the fork moving, to missing spacers, to even a fork that was sized wrong for the frame (rare, but it does happen).
If you run into this, I recommend taking your bicycle to the shop to have it checked by a professional to make certain it has all the right parts to work properly and safely. In most cases, the mechanic will be able to adjust it to work correctly. But I’ve seen enough jury-rigged threadless forks to know that there are accidents waiting to happen out there and it’s better to have it checked than to take any chances.
Tip: A common mistake is putting too many spacers beneath a stem in order to raise the handlebars for comfort. It looks like a no-brainer fix, but if the stem is placed too high and doesn’t have enough purchase on the fork steerer, watch out!
Lots of roadies just ride, and as long as the fork is doing its job and hasn’t loosened, they don’t give it a second thought. The problem is that the steerer, perhaps the most important part of the fork, is hidden inside the head tube of the frame where you can’t see it.
And on most modern road bicycles the steerer is made of aluminum or carbon, two tough materials perfect for the job — unless they get damaged. That’s why it’s important to overhaul the front end yearly. Besides servicing the headset bearings, you’ll be able to closely inspect the steerer for any signs of wear or weakness.
Look for steerer damage
Aluminum and carbon steerers (steel, too, for that matter), should look perfect inside and out. If you spot any notches, scratches, gouges or corrosion, you’ll want to get a professional opinion and may need to replace the fork.
Check all the headset parts
Also carefully inspect the headset pieces that attach to the steerer, any spacers, the stem and the compression mechanism that lets you fine-tune the headset bearings. These parts wear over time from the everyday impacts from riding over bumps that drive the fork backwards.
Clean or replace corroded parts
Some riders damage these parts through sweating, too. The salt in perspiration can slowly eat away the finish on aluminum and carbon parts and can penetrate between them where you can’t see it — more good reasons to stay on top of inspection and maintenance and keep that fork ship-shape.
For most threadless headsets to work correctly and remain tight, all its parts must be parallel to each other. But with enough hard miles the parts can wear against each other or get damaged from the weather, your sweat or improper adjustment. When this happens they can still look okay but you may not be able to make a fine adjustment. And the adjustment may change. These are signs that you should replace the worn-out parts or the headset if the individual parts aren’t available.
Tip: A hard-to-find click — sometimes it’s a squeak — can be caused by dry headset spacers rubbing against each other and/or the stem/steerer. Removing them and lubricating all touching surfaces will usually stop the noise.
I hope these tips help you keep your fork safe and sound.
Jim Langley has been a pro mechanic and cycling writer for 38 years. At RBR he’s the author of Your Home Bicycle Workshop and moderator of the technical forums on the Premium Site . Check his “cycling aficionado” website at http://www.jimlangley.net, his Q&A blog and updates at Twitter.