Author Topic: Pumping out air  (Read 6889 times)

léo woodland

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Pumping out air
« on: October 14, 2013, 10:45:26 AM »
Hi

  Every time I change the oil, I dutifully follow the instruction to pump out a quantity of air. And every time I do it, I wonder why.

  If I pump out air, it will only get back in as soon as I detach the syringe. So what does it achieve?

happy days

léo

wheezy

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Re: Pumping out air
« Reply #1 on: October 14, 2013, 10:47:17 AM »
Stop asking awkward questions.

geocycle

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Re: Pumping out air
« Reply #2 on: October 14, 2013, 11:45:55 AM »
No idea!  I did the oil change this weekend and also noted that point.  The pressure will equilibriate very quickly as soon as you disconnect the syringe.  I follow the method to the letter including the 15min cup of tea but have never understood that bit.
 

Dave Whittle Thorn Workshop

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Re: Pumping out air
« Reply #3 on: October 14, 2013, 12:15:16 PM »
If you dont and you unscrew the syringe it spits oil out, your basicly equalising the pressure before you remove the syringe.

Hope this helps, Dave.

Andre Jute

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Re: Pumping out air
« Reply #4 on: October 14, 2013, 02:01:17 PM »
I follow the method to the letter including the 15min cup of tea but have never understood that bit.

Next to their house and their car, their bike is probably the most expensive mechanical thing most people own. Well, John Saxby has his motorbike and I have some watches more expensive than my bike, but the difference is that I don't mess with the gubbins of those watches. People, probably rightly, get a bit nervous at messing with the most expensive bit of their bike, the Rohloff gearbox. It is a wonderful piece of psychology by Herr Rohloff, probably inspired by Frau Rohloff,  to tell cyclists to take a break for a restorative cup of tea. That is, dispassionately considering the remoteness of the chance that you can do damage to the gearbox merely in the process of changing the oil, by far the most important instruction: take a break, drink a cup of tea until your hands stop shaking.

energyman

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Re: Pumping out air
« Reply #5 on: October 14, 2013, 04:43:59 PM »
.............but it doesn't specify which type/flavour of tea.

Andre Jute

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Re: Pumping out air
« Reply #6 on: October 14, 2013, 07:37:51 PM »
.............but it doesn't specify which type/flavour of tea.

That choice of the tea is the bit left to you so you feel in charge (more psychology).

But I'll tell you a big secret that I discovered at this by-invitation bash in Germany where Bernd Rohloff was the guest of honour. Lady Grey tea, with extra lemon, is what real Rohloff oil-change experts drink. They all earnestly assured me so as they filched the last of the teabags I brought from home, while they changed my oil. Fortunately there was a branch of my fave supermarket in a nearby town, where I found some Rooibos, which I brewed up and hugged protectively to me, earnestly assuring them that it is the tea of men who don't get their own hands dirty at oil-change time. I must say though, my bike ran very smoothly for the year after those German experts changed my oil. There could be something in Lady Grey...

geocycle

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Re: Pumping out air
« Reply #7 on: October 14, 2013, 07:51:47 PM »
Fantastic information Andre. The lack of detail in specifying the type of tea was another major worry.  I wonder if that was the British contribution to our European friend's instructions? When writing such instructions it must be tempting to put in something utterly ludicrous to see if folk follow...!
 

moodymac

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Re: Pumping out air
« Reply #8 on: October 14, 2013, 08:53:09 PM »
As a coffee drinker I now feel intimidated!  One would wonder what impact on karma would be if a purchase of a rohloff were made?

By the way Andre, wasn't Rooibos what the newly elected official in Australia tossing around.  Are you sure that it is safe to drink?

Tom

John Saxby

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Re: Pumping out air
« Reply #9 on: October 15, 2013, 01:34:20 AM »
Tea and an oil change, and the proper kind of tea, too!  Oi, oi, oi -- getting a wee bit apprehensive about the web of ritual that seems to surround the Rohloff, until now sitting quiet and innocent (or so I thought) in my basement, waiting to assume its Rightful Place in the Scheme of Things later this winter, tucked in between the chainstays of a New Raven frame...

But Andre's story brings to mind a similar account of the discipline and order which Daily Ritual ensures in our lives:  Some years ago, a friend was living in a small country town in southern Zambia. His domestic worker, a kindly older gent named Samuel, was an ace at baking bread.  My friend, mightily impressed by the calm regularity with which Samuel produced a couple of really good loaves each week, thought that he should bring the recipe back to Canada.  So, he asked Samuel if he could write down his recipe for his superb bread. Samuel was surprised and delighted, and only too happy to oblige.

His recipe went like this:  Put flour and yeast and a little salt into a bowl.  Mix mix mix.  Add water.  Mix mix mix.  Put bowl in window in sun and cover with towel.  Take bike to town, have a cold drink, get newspaper, come home.  Punch bread, punch punch punch.  Make tea and turn on cooker to heat up oven.  After one cup of tea, punch bread, punch, punch, punch.  (Etc...)

It was a wonderful recipe, but turned out it didn't travel so well to Toronto -- my friend could never match Samuel's masterpieces. I reckon he never quite nailed the rituals.

Danneaux

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Re: Pumping out air
« Reply #10 on: October 15, 2013, 01:44:58 AM »
Quote
It was a wonderful recipe, but turned out it didn't travel so well to Toronto -- my friend could never match Samuel's masterpieces. I reckon he never quite nailed the rituals.
Humph! Obviously, it was down to the difference in distance for the bike ride to/from town...

 ;)

Wonderful story, John!

Best,

Dan.

moodymac

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Re: Pumping out air
« Reply #11 on: October 15, 2013, 01:49:50 AM »
John,

As an old and retired cop, it is obvious to me that Samuel deliberately led you poor friend awry.  Not telling him the brand of beer, or the name of the news paper doomed the recipe.
« Last Edit: October 15, 2013, 01:53:34 AM by moodymac »

Andre Jute

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Re: Pumping out air
« Reply #12 on: October 15, 2013, 02:29:02 PM »
The adrenalin pumped into my system by sitting at my desk laughing aloud probably added three months to my life. Thank you, gentlemen. You are priceless.

Off for a ride while the energy boost lasts.

mickeg

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Re: Pumping out air
« Reply #13 on: October 16, 2013, 03:26:46 PM »
I rarely drink tea but have a large cup of coffee next to my keyboard right now.  Does that mean I should have bought a different brand of hub instead of Rohloff?

geocycle

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Re: Pumping out air
« Reply #14 on: October 16, 2013, 04:22:07 PM »
No, but you will probably void your guarantee if you try an oil change!