Crankshaft end float
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Crankshaft end float
The original publications recommend .002" end float. Dragonfly is recommending .005". Why the change?
- Roger Gwynn
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Re: Crankshaft end float
Which bike would be involved here, it makes answering your question a little easier.
Roger Gwynn, Membership Secretary, curator of the Machine Register and the works drawings. Director of Draganfly Motorcycles, Craven Equipment and Supreme Motorcycles mostly retired.
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Re: Crankshaft end float
I am restoring a 1958 Ariel Square 4..
- Roger Gwynn
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Re: Crankshaft end float
The Draganfly web site says "The crankshaft end float should be .003” to .004” on the front crank and .005” to .006” on the rear. Ariels only ever listed shims to increase the end float, not to decrease it; these may occasionally be found fitted outside the timing side main bush." This is what is quoted in the Waller book. Checking the later 1956 owner's guide I see that Ariel say .002-.004 for both cranks. It should be a small amount to ensure that the cranks are not nipped up but as little as possible.
Roger Gwynn, Membership Secretary, curator of the Machine Register and the works drawings. Director of Draganfly Motorcycles, Craven Equipment and Supreme Motorcycles mostly retired.
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Re: Crankshaft end float
My concern stems from twin cylinder BSAs who's oiling system is similar to the Ariel's; .006" is way too much, starves the left hand rod.
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Re: Crankshaft end float
Big difference between BSA (including Huntmasters) and Ariel 500s and Fours is that the
former have decent sludge traps which the latter don't and the latter have oil seal washers
on the outside of the timing side bushes which the former don't. BSA didn't get round to
fitting them until the A70 twins. 6 thou end float on a roller bearing A65 is indeed an
impatient disaster.
former have decent sludge traps which the latter don't and the latter have oil seal washers
on the outside of the timing side bushes which the former don't. BSA didn't get round to
fitting them until the A70 twins. 6 thou end float on a roller bearing A65 is indeed an
impatient disaster.
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Re: Crankshaft end float
The term oil seal washer is a tad odd; is there supposed to be any rubber on them? Mine, which appear to be original, are just plain steel. Did I mention that this is a bike in a box, disassembled in 1978?
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Re: Crankshaft end float
No rubber. As you say, just plain steel but I think they only fit one way round.
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Re: Crankshaft end float
The inside of the seal is beveled but it will fit either way.
- paul.jameson
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Re: Crankshaft end float
The bevelled side goes inwards, towards the main length of the crank. The bevel is to cope with the tiny radius at the change of crank section.
Paul Jameson
35 LG (project), 37 RH500, 52 ex ISDT KHA, 54 KH(A), 75 Healey 1000/4.
Former Machine Registrar & Archivist, General Secretary and Single Spares Organiser (over a 25 year period).
Now Archivist (but not Machine Registrar), Gauges and Clocks Spares Organiser.
35 LG (project), 37 RH500, 52 ex ISDT KHA, 54 KH(A), 75 Healey 1000/4.
Former Machine Registrar & Archivist, General Secretary and Single Spares Organiser (over a 25 year period).
Now Archivist (but not Machine Registrar), Gauges and Clocks Spares Organiser.
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