Propel summer service


Sara’s Giant Propel Advanced Pro 1 is just over 9 months old and having been regularly ridden throughout that period, it was time for a full service in preparation for the looming summer.

Dubai can be hard on bikes as the hot dusty climate creates a perfect storm of conditions to allow grease to gradually disappear and grit to get in to components, joints and bearings.  Ideally your bike should be continually looked at and kept on top of, but what kind of sad, feckless waster has time for that?


The easy option of course is to drop it in at one of the Local Bike Shops (LBS) who will do it all for you for a small (or not) fee.  However doing a full service on your own bike is well within the scope of the home mechanic or enthusiastic amateur.  Remarkably few special tools are required and the ones I used added up to about 200aed in total.

Basic tools needed for a bike service

OK, there is no doubt a Troque wrench is ideal for all work on a bike, especially Carbon Fibre components, but if you have a little mechanical feel you can get away without one.  Saying that at 150aed from Wiggle they are not exactly expensive.


First order of the day was to clean the chain, it seems obvious, but working on a bike after the chain has been cleaned is much nicer.  I generally just use some petrol from a jerry can I have sitting around to get the bulk of the crap off the chain, then use de-greaser and a chain cleaning tool to finish off.

Once the chain was reasonably clean, time to strip the bike down to the bare frame, removing all the components that need servicing.  Wheels, forks, head-set, crank, chain-set, seat-post and brakes were all removed for inspection, cleaning and lubing.

Stripped down Propel

A quick inspection once stripped down revealed no obvious nasties, but lots of sand and grit everywhere.  One area that I have seen a few problems recently on bikes, is the head bearings that support the steerer tube, especially the lower bearing.  Gravity and heat have their way with this bearing and evidence of the grease leaching out can be seen on many bikes after even a short ride in the heat.

Stains below the bottom head bearing indicate gradual leaching of grease

Over time this bearing can dry out and steering can become quite knotchy or loose, often resulting in the need for new bearings.  Thankfully Sara’s still had plenty of grease, even if the surrounding area was pretty dirty.

Looks worse than it is, all the sand and grit is outside the bearing area

Bearing removal and cleaning is a matter of using your fingers to remove bearing from the cup, cleaning the bearings and cups with a rag and then re-greasing them.  This is really a 15 minute job with the only tool required being a 4mm Allen key.

Onwards to the depth’s of the Bottom Bracket (BB).  Until you pull yours apart you probably think this is something mysterious and complicated, but it is really not.  There is only one special tool required to remove a Shimano front crank and chain-set, this being is a bung plug socket, apart from that all you need is a 5mm Allen key

Shimano crank bung removal tool

Once stripped of the crank and chainset, you can see that the bottom bracket bearing seals have done a great job in keeping the dust and sand out of the bearings, just as well, as replacing bearings especially in a press fit BB like the Propel is a bit of a bigger job.  So with no evident wear or damage, clean and lube, once again order of the day.

Grit and sand outside BB area

Chain rings and crank were also checked and cleaned, with no significant wear, as you would expect on a relatively new bike.

Ultegra crank and chain-set

Onwards to the rear dérailleur, which was partially disassembled for servicing.  The jockey wheels on the rear dérailleur are worth taking apart, as they often get cluttered up with rag threads from chain cleaning and coated with old chain lube.


Sara’s were pretty clean and in good nick, soA quick clean and lube of the ceramic bearings on the jockey wheels with some Teflon chain lube was all that was required.

Lubing ceramic bearings on jockey wheels

Next to the wheels and cassette.  Removing the rear cassette on a bike requires two fairly cheap special tools, a chain whip to hold the cassette and a special cassette socket to undo the centre retaining nut.  Possibly the best investment for a road cyclist tool-wise, as this enables you to swap cassettes in a matter of minutes.  Useful if you plan to stray from the flatlands of Al Qudra to something more challenging like Jebel Jais.

Ultegra cassette, a little wear, but generally OK

To the uninitiated a disassembled Ultegra cassette looks like a complicated thing, but Shimano has made them virtually impossible to assemble in the wrong way, at least if you have your eyes open that is.  Simply put if it looks right, then you have done it right.  Sara’s cassette had a bit of wear, but considering the mileage she has done in 9 months, well within what is expected.  Her chain had been recently replaced, so that required nothing more than a re-lube.

Wheel bearings were inspected and required nothing but a dab of grease and a clean.  The freehub was removed from the rear wheel, as it was starting to get a little noisy.  The Giant wheels on the Propel have a free hub made by DT Swiss, a quick clean, grease and reassembly made things much quieter and noticeably smoother.

Free hub ratchets, clean and lube with a little grease

All shifting and brake cables were inspected and found to be in good working order. A squirt of Teflon spray was put down the J tubes on the brake fittings, as these areas are prone to ingress of sweat and can corrode the cables, especially on the rear brake.

The final thing to service on the Propel is the Aero SL brakes which are made by TRP.  This is one of the reasons I suggested the service to Sara, as if Propels have one weak spot, it is the bearings on the Speed Control SL brakes.  These need regular servicing, as with heat and sweat the Cadmium plated bearing caliper pivot can seize up and is an utter bu**er to disassemble when it has seized.


The way to identify if you have a problem with these brakes, is if there is any stiction or drag, when they are meant to spring back from the rim.  If you find yourself adjusting the spring tension on one side to balance the gap, then you may also have a problem.

The Propels brakes are fantastic in use and must save at least 3 watts by their Aero design, which as we all knows really matters, especially if you have a pathetic little engine like me! Relatively easy to take apart, it is a 20 minute job to do all 4 brakes, only tool required a 5mm Allen Key.  Simply put if these brakes are serviced regularly, say every 6 months, there is no issue.

Disassembled Giant Propel Speed Control SL brakes
Disassembled Giant Propel Speed Control SL brakes

Sara’s rear left pivot showed a little wear on the plating, but nothing a smear of grease couldn’t fix

Plating on bearing pivot
Plating on bearing pivot

Most Ultegra group-set bikes won’t feature the above brakes and with “normal” Ultegra calipers their is less of an issue.  But the old adage stands, five minutes of maintenance can save hundreds of dollars, lots of time, and tons of heartache.

The rest of the service, was a matter of cleaning, checking and lubing as appropriate.  Total time taken was just over 2 hours, probably less time than it would take me to drive to the LBS to deposit, then return to pick up the bike, way more fun and considerably less expensive.

Remember YouTube has instructions on every single facet of bike servicing, you are not alone, who needs phone a friend, when you can watch a video.  Go on have a go, service your own bike, you know it makes sense.


4 thoughts on “Propel summer service”

  1. Hi, this is really useful! How are the brakes disassembled? I think mine have seized, so assume it is going to be a bu**er to do, but not sure how to get the bearing pivot off?

    1. Hi Lewis, the bearing just pulls apart as in the picture “Disassembled Giant Propel Speed Control SL brakes”
      However if they are pretty well seized then it can be a bit of a sod, try spraying with copious amounts of WD40 and leaving for a day or two, or putting in a ultrasonic cleaner.
      If your brakes are badly seized the plating on the cadmium plated bush is likely to be damaged and may be past its usability as a bush. if it is that far gone, I really suggest you buy a set of the Fouriers Direct Mount Aero V Brake For Giant Propel that are available on eBay etc, they are much better than the 1st Generation Giant SL ones and also allow you to use 25mm tyres much easier.

      1. Half a can of GT85, some pliers and a lot of much stronger language than sod and bu**er and I’ve managed to get all 4 arms disassembled , cleaned up and moving freely! Thanks so much for the article and response to my comment. Absolute saviour!

        1. Very welcome, if you keep on top of lubing these brakes they are excellent, but as soon as they get a bit corroded they are a bitch. I do mine about every 3 months, only takes about 15 minutes to do all 4

Leave a Reply

Your email address will not be published. Required fields are marked *