Preventative Maintenance: Frame, Fork & Bearings

Mark Livingood Technical

This is the second of five articles in a series that address Preventative Maintenance for your tandem.

tripletframe

The heart and soul of your tandem are the frame and fork and they’re often the most neglected parts of the bike, short of an occasional cleaning.

Frame Checklist & Tips:

There’s nothing worse than seeing a possible crack in a frame and wondering, “How long has that been there?”  Speaking of which, I strongly encourage owners to ‘baseline’ what their frame looks like so that they’ll be able to recognize any changes that occur after a drop, hard hit, travel, etc.   If you don’t trust your memory of such things, you might want to take down some notes in a maintenance journal and/or take a set of detailed photos and note pre-existing flaws.  You’ll want to update your mental, written or photo notes as you “add character” to the frame.

With that as background, and while you should always give your frame and fork a good look-over after any incidents where it takes a hit or fall and on a regular basis or while doing a little maintenance or cleaning, you’ll want to take time at least once a year to give your tandem’s frame a deep-cleaning and inspection.

  • By deep cleaning, consider a wash using Dawn dishwashing soap, as it will remove just about any grease as well as old coats of wax so you can get down to the clear coat or base frame material.  Don’t worry about getting the Dawn on your lubricated parts, those all need to get degreased and cleaned too.
  • On painted or powder coated frames, follow up the wash by hand cleaning/polishing the frame and fork with a mild polishing compound, making sure you work your way around all the tubes, welds, and fittings. For unpainted composite, aluminum, and titanium frames, follow your builder’s instructions for frame care to get the best results.
    • VGBTGAs you clean / polish you’ll want to look for dents, cracks or other damage while touching up any scratches or nicks in the finish to prevent corrosion or rust.
    • If you find any damage you weren’t aware of —  possible cracks, de-lamination, dis-bonds, corrosion or other potential issues — take photos and send them to your tandem’s builder for a preliminary assessment.
    • Remember, if you’re the original owner most bicycle frames come with fairly comprehensive warranties which might cover any non-accident related latent defects in your frame.
  • If you happen to have a tandem that is fitted with a rear suspension system, those will also need some specific attention. For air or air/oil/gas shocks, be sure to inspect the seals for leaks and to make sure any Schrader pump valves are fully seated. Also, be sure to check all the rockers, bolts, and fittings for any signs of fatigue. 
  • Assuming all appears well and good after you’ve cleaned, polished and inspected your frame, give it a fresh coat of your favorite wax and you are done!

Fork Checklist & Tips:

As you might expect, everything mentioned for the frame also applies to the fork with just a couple of added considerations:

  • forkcrackFor tandems that see a lot of use I recommend removing the fork at least once a year for deep cleaning and inspection, in conjunction with headset bearing maintenance.  For lightly used tandems, consider every two to three years.  For rarely ridden tandems, at least every five years.
  • You’ll want to pay particular attention to the steerer tube, fork crown and junction where they meet, especially for composite forks.  Other areas to pay attention to include the drop-outs which, on composite forks, are typically bonded into the ends of the composite fork tubes.  If your fork has bosses for cantilever / linear-pull / V-brakes, those also warrant a close inspection.
  • If you think you see what appears to be a crack developing take some well lit, detailed photos and send them to your builder or the component’s manufacturer for a preliminary assessment.
    • Again, and as noted for the frame, most builders, their fork suppliers and after market fork manufacturers have pretty comprehensive replacement policies where original owners can typically buy a replacement component at dealer cost or less if a part has prematurely failed from fatigue during normal use.
  • If you happen to have a tandem that is fitted with a suspension fork that will need some specific attention. For air or air/oil/gas shocks, be sure to inspect the seals for leaks and to make sure any Schrader pump valves are fully seated.  If you have an oil dampened fork, when’s the last time you changed the fork oil?  Also, be sure to check all the bolts, fittings, clamps and steerer for any signs of fatigue. Those older Cannondale FR4Ts and many other older suspension forks from the late 90?s and early ’00?s bear close monitoring. A fork failure on a tandem ridden on technical single track could easily land both the captain and stoker in a hospital with serious injuries!

Bearing Checklist & Tips:

Now’s as good a time as any to address bearings, as you’ll have already encountered at least two if you removed your fork as suggested above.

  • You’ve got bearings in your headset, bottom brackets, and wheels.  If you have a full-suspension tandem, you may have several others.
  • You’ll find both loose bearings and sealed cartridge bearings on better quality bicycles.  For example, Shimano typically uses loose bearings in their hubs, whereas White Industry, Phil Wood, and Chris King used sealed cartridge bearings.
  • Screen Shot 2014-02-08 at 11.50.50 AMI find that there’s a widely-held belief that sealed cartridge bearings never need to be serviced.  Well, that’s not exactly true.
    • While sealed cartridge bearings are certainly LOW-maintenance they are not NO-maintenance: see excerpt from Chris King headset instructions at right.
    • I’ve seen Phil  Wood hub bearings that had a little bit of rain exposure last 30,000 miles over 10 years before they needed to be replaced and have heard of others that lasted longer.  Then again, the sealed bearings on our off-road tandem’s bottom brackets that were immersed in water several times looked pretty sad when I pulled-off the dust seals: yes, those are dust seals not water-proof seals on those “sealed” bearings.
  • Therefore, you have two ways to go with regard to bearing maintenance.  You can use them until they become damaged, or you can make a point of cleaning and re-greasing them on a periodic basis as part of your preventative maintenance plan.
    • If you don’t have the tools or skills needed to do this maintenance, you can probably have a qualified bike mechanic inspect them for wear each year and service or replace as needed.
    • If you opt for the run ‘em until they stop running and do your own wrenching, you’ll want to use your annual spring check up to spin the axles and other rotating parts by hand to see if you can detect any excessive play, binding, or a gritty feel that may be indicative of a worn part.
  • If you’ve never serviced bearings and are curious to see what all’s involved, there are lots of great videos out on the internet that show you the step-by-step process.  Here are links to two examples; one shows how to go about servicing a Shimano hub with loose bearings, and the other addresses sealed cartridge bearings:

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