Author Topic: 53' plunger front forks  (Read 353 times)

Offline Tone

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53' plunger front forks
« on: 17.03. 2017 13:56 »
Hi all, I'm going to fit a fork upgrade kit to my plunger forks, ie, double damper, springs etc, my question is about the amount of oil in each fork? because the amount stated for a plunger a10 is a lot less than for the later swing arm ones, and I'm wondering if the double damping will work with such little oil! Your thoughts will be very much appreciated, cheers Tone.

Online JulianS

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Re: 53' plunger front forks
« Reply #1 on: 17.03. 2017 16:54 »
Tone

The 1952 on  forks should take 3/8 pint or 212cc of oil, same as the later models.

With the damper rods you do need to make sure that they are in the oil or you will not get the full effect of the damping and when riding you will sense a slap as oil and underside of damper valve meet as forks compress.

You may find that the damping on extension not as effective as damping on compression. I think this is because on compression only the oil is confined between fork bottom and damper valve but on extension the oil plus all the compressable air in the fork leg is confined between damper valve and underside of the fork top nut.


Online muskrat

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Re: 53' plunger front forks
« Reply #2 on: 17.03. 2017 19:53 »
G'day Tone
I have them in my 51 plunger. I can't remember how much oil but as JulianS states the oil must be over the valve at full extension. I measured the height of the std amount of oil, then made the rod length to just submerge the valve. Works great.
Cheers
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
Australia
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Offline Tone

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Re: 53' plunger front forks
« Reply #3 on: 18.03. 2017 08:21 »
Thanks guys, anything will be better than it is a the moment, cheers, Tony