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The Bearings We All Forget

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Bearings

Bicycles run on bearings.  Starting from the front of the bicycle, there are bearings in the front wheel hub, which allow the wheel to spin on its axle.  There are bearings in the headset, which is the assembly that connects the front fork to the frame, and permits the fork to turn for steering and balancing.  There are bearings in the bottom bracket, which allow the crankset spindle to rotate freely.  There are bearings in the rear wheel hub and the freewheel attached to it.  There are bearings in the two rear derailleur pulleys.

Bearings Bicycle.png

Cyclists pay lots of attention to the bearings in wheels and drivetrains.  These are the bearings which help the bicycle’s forward progress.  Any reduction in friction (loss of watts, in cyclist’s parlance) is highly sought after.  These bearings are regularly serviced. Steel bearings are often replaced with ceramic bearings, which have a lower rolling resistance.

Headset bearings get less love.  Bike mechanics should check headset adjustment when servicing bikes.  Occasionally a headset needs tightening.  It is usually only after the rider feels roughness, notchiness, or uneven drag while steering, that headset bearing get serviced or replaced.

And the bearings we all forget?  The ones in our pedals.  Cyclists notice when their cleats need replacing.  The wear is visible, and that wear is often made tangible by clipping in and out of the pedals requiring either too much or too little force.

Pedals just seem to go on and on doing their job with no fuss or bother.  That adage about the squeaky wheel is certainly true where pedals are concerned.

I bought my Alchemy Eros, and the Speedplay pedals that I specified for the bike, in June 2015.  I had given my pedals little or no thought since then.

A week ago the bike developed an irritating click.  Lim, the mechanic at The Bike Artisans, thought that my pedals could be the source of the noise.  The pedals were spinning too freely on their spindles, which is a sign that they needed regreasing.  He didn’t have a needle-type grease injector gun, so couldn’t do the quick and easy pedal maintenance via the grease port hole built into the pedal bodies.

When I got home I consulted the Speedplay website.  Speedplay recommends that the pedal bearings be regreased at least every 3,200 km / 2000 mi, or every two months.

Bearings What

That means my pedals should have been regreased between five and twelve times by now.

I found online instructions to disassemble my pedals.  The Spindle Screw was held in place by some Loctite Threadlocker Blue, but I got the screw to turn without having to heat it, as mentioned in some posts.  The fiddliest step was removing the retaining ring.

It is possible to replace the bearings – Speedplay sells a pedal rebuild kit for USD100 which replaces everything but the spindles.  I just cleaned all the parts, flushed out what grease was left in the bearings, flooded the pedal body with fresh grease, and reassembled the pedals.

Bearings Pedal Disassembly

Diagram courtesy of forum.slowtwitch.com

So far so good.  The pedals are turning smoothly and quietly.

Unfortunately that irritating click is still there.

Bearings Irritated

Postscript

I have found the source of the click.  It was coming from the rear dropouts.  A touch of lubrication between the QR faces and the dropouts, and silence was restored.

Thank you Uffe Lindhardt for the link to Keep It Quiet!  Jim Langley’s wide-ranging bicycle blog is an excellent resource.

New BB for the Alchemy Eros

Bottom Bracket (BB):  The bottom bracket connects the crankset (chainset) to the bicycle and allows the crankset to rotate freely.  It contains a spindle or axle that the crankset attaches to, and the bearings that allow the spindle and cranks to rotate.

From Wikipedia, the free encyclopedia

In my post about my broken saddle, I mentioned that I was told about the snapped rail after I sent the Alchemy Eros to Meng Thai Cycle for servicing.  The bike needed a service because the BB was clicking sporadically.

The bike came with a Chris King BB.  After the crankset had been removed, the mechanic discovered that the BB bearing on one side of the BB shell was almost frozen.  As the BB bearings came out of the BB shell, a gush of water followed.

The Eros frame does not have a drain hole in the BB shell, or in the chain stays.  So the water that found its way into the frame, most likely by wicking down the seat post, accumulated in the BB shell.

This is what a new Chris King Press Fit 30 BB looks like.

Chris King PF 30

Photograph courtesy of Chris King

This is what came out of my frame.

IMG_5798

Clearly, the water in the BB shell had not done the bearings any good.  The damage was so bad that the BB had to be replaced.

Chris King BBs are hard to find in Kuala Lumpur.  Meng Thai Cycle had a compatible Tripeak Twist Fit BB on hand.

Tripeak Logo

Logo courtesy of tripeakbearing.com

I had read about twist fit BBs in the past.  They were touted as an elegant solution for creaking press fit BBs.  In April 2015 BikeRadar published a piece about Legit Engineering’s twist fit BB.  Seventeen months later, road.cc published an article about the similar Token thread fit BB.

Both versions feature bearing cups wrapped in a plastic and fibreglass composite material.  This prevents metal-to-metal contact between the bearing cups and the frame, thus eliminating creaks.

The clever part of this solution is that the bearing cups thread together, tightly sandwiching the BB shell in between the cups to prevent movement.

Tripeak PF30 Twist Fit BB 4

Photograph courtesy of tripeakbearing.com

The Tripeak name was new to me.  It turns out that Legit Engineering has been rebranded as Tripeak.  Click on the link on the URL shown on the Legit Engineering Facebook page and you get taken to the marketing site for Tripeak.   The Legit Engineering Twist Fit BB (upper photograph) and Tripeak Twist Fit are are identical, save for branding.

Legit Twist Fit BB 1

Photograph courtesy of bikeradar.com

Tripeak PF30 Twist Fit BB 3

Photograph courtesy of tripeakbearing.com

After more than 15,000km / 9,300mi on a Chris King PF30 BB, my cranks now turn in a Tripeak Twist Fit BB.  So far so good.

Chris King BBs come with a 5-year built-to-last warranty.  I sent photographs and a description of the problem to Alchemy Bicycle Co.  Alchemy was whom I had “bought” the Chris King BB from when I purchased my fully built-up bike.

Alchemy has submitted those details to Chris King, but have not yet heard back from them.  It is a limited warranty, so it is very likely that damage or failure due to water in the BB shell is not covered.

Which reminds me to take my Alchemy Eros outside, remove the seat post, and turn it upside down.  I have been on some wet rides lately.

N.B.  Taiwanese brands like Tripeak are often hard to find in the United States and Europe.  Wheels Manufacturing now offers a range of threaded BBs to replace press fit BBs.

Tick Tick Tick

It stands to reason that as soon as ISKY 1 stopped creaking, ISKY 2 would start ticking.  As with the apparent source of the noise from the purple bike, the ticking seemed to come from the bottom bracket of the orange bike.

Hoping to benefit from past experience, I started my hunt for the source of the tick with the rear hub.  It was in a better state than the one on ISKY 1 had been.  It still needed to be cleaned and re-greased.  The freewheel runs quieter now. But the ticking persisted.

The next step was to remove the cranks and take a look at the bottom bracket.  The bearings looked fine, apart from needing a good clean and some fresh grease.  I did discover this though.

Disc Spring

This disc spring sits on the drive-side crank spindle.

There is a new disc spring in place of this cracked one now.

ISKY 2 is still ticking though.  But, unless I am imagining things, not as loudly as before.

The optimist in me thinks the ticking will just fade away.

The realist in me knows that there is more work to be done.