Changing the bearings in the uprights and a weekend at Gurston Down

The big one. Changing the bearings in the front uprights.  I’d looked it up on the internet and been sent a set of instructions by Simon at Universal.

So its a two step process – remove the central hub from the bearing – then remove the bearing from the upright.  Because of some later problems, I drew it all in Onshape.

The bearing is shown in a sort of yellow, the hub grey and the upright black.

To remove the hub from the bearing you need to support the flange somehow and press the bearing off by pushing pins through the holes in the flange.  (Whilst I’m at: nothing shown on this blog is meant to define a definitive safe way of working – its how I did it and I may have taken some risks that aren’t recommended.)

Problem 1: I used silver steel rods, and the first set bent before the bearing even moved.

I cut a set of rods which only projected a small amount. And when I pressed on these the whole assembly made a sort of clunking noise and the hub started to move.  I cut two more sets of pins and managed to push the hub right out.  Excellent. Pushing the bearing out of the upright was relatively simple.  Job done; well half done at worst.  What’s the word?  Hubris, that’s it.

When it came to repeating all this for the other side, things went wrong quite quickly.   The first evidence of this was that I managed to push the first set of rods all the way in without freeing the hub.  There was no way to get them out.

Problem 2: No way forward as I couldn’t remove the pins

A good friend of mine, Derek Knight, a toolmaker by profession, has a very well equipped workshop, and he managed to remove the bearing by effectively removing critical bits of it. No exaggeration to say that he has saved the day.  As well as being seized in there seemed to be evidence that the hub had skidded in the inner race.  Time for a new hub from URS.

Having completed all this the Midland Hillclimb event at Gurston was next on the calendar.  Being third in the B Championship meant that I was focused on gaining a few points – nobody above me in the league table had entered.  The weekend was hot – on Saturday very hot.  I managed to put in a few times under 47s – one faster than I’d been up the hill without a cage (making the car quite a bit lighter).  However on my first competition run I missed a gear on the run to the finish line.  Nearly 3 seconds slower than my fastest run, but still amazingly, the fastest 1.4 runner.  A somewhat pointed approach to gearshifting in my second run meant that I only put in a semi-decent time, but still fastest 1.4 and hopefully highest scoring Midland B entrant.  I’m somewhat impatient to see the latest Midland positions!




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