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Offline edger

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Fork oil /air gap
« on: 24 January, 2018, 04:18:04 PM »
2009 MK 1
Is it me or what?
Changing the fork oil today Haynes say 437 cc plus or minus 2.5 cc and 129 mm air gap.
However if I put in 437cc the air gap is 95mm?
To get a gap of 129mm I must remove 30cc of oil
AM I JUST BEING DUMB / Have I missed something?
Have Honda changed the spec's, is it a miss print in the Haynes

Going out to walk the dog now and try chill a bit before resuming.
Any and all suggestions are good (and yes I have searched  :mfrlol:)

Offline jm2

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Re: Fork oil /air gap
« Reply #1 on: 24 January, 2018, 04:26:42 PM »
Air?  Did the level settle at all when pumped?
Only do it right - no bodging please.   Keeper of the failed stator list.   John.

Offline edger

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Re: Fork oil /air gap
« Reply #2 on: 24 January, 2018, 05:43:53 PM »
As far as I know  its all good ..But its still wrong if you get my drift.
I took the dog out for a hoon round the woods to allow time for the oil to settle and air escape  back now still the same.
I will leave it over night and start again tomorrow.

Offline Bifferman

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Re: Fork oil /air gap
« Reply #3 on: 24 January, 2018, 06:21:54 PM »
Edgar

The MKI Honda Service Manual is particularly good at explaining how to drain and reflil the forks.  Worth reading.  I presume you have downloaded a copy.

It does sound as if you had not drained all the old oil out OR you still have air in the refill.  Obvious really because it can't be much else.  Did you use SAE10W grade.  As I said the HSM is VERY good on this.

Andy
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Offline edger

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Re: Fork oil /air gap
« Reply #4 on: 24 January, 2018, 08:33:25 PM »
I am sure all the old oil was out, they were upside down suspended from my work bench for the best part of a week The old oil was 15wt but felt to harsh on anything other than perfect road surfaces  so I reverted to 10wt and was going to fit spring preload spacers
I went daft and treated myself to a Ohlins rear shock  so sorting the front is my aim now without breaking the bank anymore than I  already have.

I have never had a problem changing oil and springs in the past but this has me stumped.
If they haven't settled by tomorrow I will drain them again and start again,
Sometimes its best not to fiddle in the first place :mfrlol: good thing the weather is pants gives me time to get the stove going in the shed and whirl the spanners .
New tyres are waiting for spring fitting.

Offline Ali-bear

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Re: Fork oil /air gap
« Reply #5 on: 25 January, 2018, 10:24:50 AM »
*Originally Posted by edger [+]
Changing the fork oil today Haynes say 437 cc plus or minus 2.5 cc and 129 mm air gap.
However if I put in 437cc the air gap is 95mm?
To get a gap of 129mm I must remove 30cc of oil

129-95=34mm.
30cc is a slightly generous single spirits measure.

I would ignore that part of the Haynes instructions. Having said that you can modify the effective spring rate by adjusting the amount of air. My Hyperpro springs came with a recommended air gap smaller than standard.
Designed in Japan, assembled in Italy, fiddled with in Britain

Offline edger

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Re: Fork oil /air gap
« Reply #6 on: 25 January, 2018, 01:47:46 PM »
OK so I have put it all together again and measured off the top of the tube to the surface of the oil 129mm (near as spit)
I knew I should have left well alone!
Just got to stick the wheel back in and we're good to go.

Offline DCSF

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Re: Fork oil /air gap
« Reply #7 on: 07 August, 2018, 04:32:26 PM »
Hi
I am fitting wilbers progressive springs on my 2008 Mk1...any idea what air gap I would need?

Offline richardcbf

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Re: Fork oil /air gap
« Reply #8 on: 07 August, 2018, 07:55:11 PM »
(No one ever said on their deathbed, "Gee, I wish I had spent more time alone with my computer." Danielle Berry.) http://hmpg.net/

Offline DCSF

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Re: Fork oil /air gap
« Reply #9 on: 07 August, 2018, 10:38:34 PM »
Ah that's excellent...many thanks.
Instructions don't mention it...never thought of looking at website  :164: