Author Topic: Left hand thread axles  (Read 4440 times)

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Offline cardan

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Left hand thread axles
« on: 02 May 2015 at 10:15 »

What a bizarre thing the Douglas left-hand-thread-at-each-end draw-out axle is. I've just come across one in nice order, complete with nuts and thick flat washers. What models used this setup? What were they thinking?

Leon

Offline eddie

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Re: Left hand thread axles
« Reply #1 on: 02 May 2015 at 12:07 »
Leon,
         I once mentioned to Bill Douglas that his great grandfather must have been a cantankerous so and so - fitting his bikes with all those odd threads. Bill's reply was - "No, he wasn't cantankerous - he was a canny scot who knew he couldn't make much profit from the bikes, so made sure owners had to go back to him for their spares!"

  Regards,
               Eddie.

Offline cardan

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Re: Left hand thread axles
« Reply #2 on: 02 May 2015 at 23:41 »

Thanks Eddie. That's an excellent explanation! I wonder how many restored bikes still use the left/left axle, and how many use something more "normal". If anyone wants to ensure that the next owner of their bike will go purple trying to remove the wheel nuts (or better still wants to secretly swap axles on a friend's bike then drive a nail though the tyre), let me know as I have no use for the axle, other than as a marvellous oddity from times long gone.

Leon

Offline Alan Cun

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Re: Left hand thread axles
« Reply #3 on: 03 May 2015 at 09:28 »
Hello All,
The left hand thread appeared on the EW Doug mainly because the 8 in brake is on the left side of the bike and the dust cap on the right side actually adjusts the axle tapered bearings. The theory is that if the bearing locks up the left hand thread unwinds against the fork and doesnt lock up the front wheel. This is what I have seen somewhere in my docs. In Aust if you have access to Dodge Valiants from years ago they had 20 TPI wheel nuts that go perfectly on the axle. From my experience the EW 350 and 600 both had 7/16 LH axles. Though 29 600 had 1/2 LH axles.

Now if we look at the OHV models they had the input to the gearbox on the left and the output on the right. If you study the OHV models you will see the 8 in brake on the R of the machine. Now my OHV models have RH thread axles mostly 1/2 dia.

Thats the way I have noticed anyway.
regards Alan

Offline Hutch

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Re: Left hand thread axles
« Reply #4 on: 04 May 2015 at 06:59 »
Hi all,
Of course that would be the left handed wheel nuts on the left hand side of the Chrysler Valiant - the ones on the right hand side are right handed! I seem to remember this from the days when my dad had an AP5 Valiant!

-Ian

Offline cardan

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Re: Left hand thread axles
« Reply #5 on: 04 May 2015 at 09:42 »

Silly me, the axles are not draw-out as I said in the first post, but are 1/2" in the centre section, stepped down to 7/16 for a plain section then the LH threads.

I say axles because I found another today. The same detail for centre section, but about an inch longer in the threads.

Alan you make a good point, but as Ian points out the best setup would possibly be LH on one side and RH on the other. I wonder how many owners struggled to get the wheel nuts off their Douglases, or indeed the left side of their Valiants!

Cheers

Leon

Offline Doug

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Re: Left hand thread axles
« Reply #6 on: 04 May 2015 at 15:04 »
There are numerous permutations of axles. Beside different lengths (sometimes the variation is just on one end) there are 7/16 and 1/2 inch diameters. Generally they moved towards the more robust 1/2 inch axle, but then regressed on the 600 Aero models by going back to a 7/16 axle at the front.

When I say robust, I mean that only as a relative term! Though made of a nickle alloy steel, I reckon the flexible axles were the ruination of many a taper roller bearing.

-Doug

 

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