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Offline Robo

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Re: Fork oil Refresh with a slight Modification.
« Reply #20 on: 15 February, 2016, 07:03:41 PM »
*Originally Posted by Bifferman [+]
Robo

By adding your 23mm spacer + 2mm washer the fork spring will be compressed another one inch which in turn I guess would make the front suspension a good bit stiffer.Correct  Apart from the fact that 25mm = 1 inch was there any other 'science' that led you to compress the spring by that further amount.  Before aftermarket springs and air the old school trick was to add an inch and go from there,if you think I'm pulling your leg , phone Alf Hagon's shop and pick their brain.

Secondly, does your modification make a noticeable difference to the front forks i.e. is there slightly less dive when you brake or what ?Yes , it depends what you want

Lastly, to make life easier when I come to reassemble the innards I was to reduce the spacer to say 18mm (+2mm for the washer) whould this IYO reduce the stiffness noticeable or, put another way, would it still be worth doing a revised modification.you can mess around reducing oil also, but the more oil you add the chance you will blow a fork seal, the same as adding a bigger spacer, but if you add a bigger spacer/oil/ it will stiffen up to much/go hard and be unridable.
1 inch is a good base line ,you can always reduce it to suit.


Another lastly :015:, Are there any other bits that you would suggest are replaced when changing the oil i.e. the bush guide and/or the oil seal stop/ring (item 12 on the Lings exploded diagram).not with the miles you have put on it.

I intend either buying the extension collar and washer or scrounging from someone - you haven't got a spare one have you :164:.
I have spare tube the correct diameter but no washers, a guy on Ebay laser cut me a pair for a few ££ , or buy the washers from Honda. 

When I do this I will be replacing the steering race bearings for the tapered 'All Balls' ones sitting in my spares bin.

Thanks in advance.

Andy
If theres a gap i can get through it !!!

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Offline bbatarelo

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Re: Fork oil Refresh with a slight Modification.
« Reply #21 on: 16 August, 2016, 01:18:07 PM »
*Originally Posted by Bifferman [+]
Robo

By adding your 23mm spacer + 2mm washer the fork spring will be compressed another one inch which in turn I guess would make the front suspension a good bit stiffer.  Apart from the fact that 25mm = 1 inch was there any other 'science' that led you to compress the spring by that further amount. 

Secondly, does your modification make a noticeable difference to the front forks i.e. is there slightly less dive when you brake or what ?

Lastly, to make life easier when I come to reassemble the innards I was to reduce the spacer to say 18mm (+2mm for the washer) whould this IYO reduce the stiffness noticeable or, put another way, would it still be worth doing a revised modification.


As Robo mentionend, it depends on what you want. 25mm is IMO the maximum preload you should add. It almost binds "progressive" section of springs leaving you very soon in compression cycle with stiffer springs. By preloading spring, you are permanently storing more energy in it and on a rebound stroke suspension will resist less then before. That can cause instability that can be addressed in several ways. Popular way is adding thicker oil which will also affect compression stroke. You might or might not like it, or even feel it. Also there's a possible suspension wear in the long run if you thicken the oil too much. This is a "poor man's" modification which might work OK if you don't exaggerate and if you know what you want to achieve.
In the end, nothing can replace properly tuned suspension according to rider's weight and needs, but we are talking about orders of magnitude rise in costs compared to the solution above.

Bruno

Offline Markytp

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Re: Fork oil Refresh with a slight Modification.
« Reply #22 on: 16 August, 2016, 06:28:47 PM »
Silly question that I'm surprised hasn't been asked before........

Why don't we do a poll of things / jobs we would like to learn to do, then all chip in, pay Robo for a weekend of his time and we all meet up and have a weekend of "How to.....", a few sherberts, food and a bloody good laugh??  :001:

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Offline Robo

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Re: Fork oil Refresh with a slight Modification.
« Reply #23 on: 16 August, 2016, 07:58:44 PM »
 :031: :031: :031: :028:
If theres a gap i can get through it !!!

Some people pay for an IAM... I am mad.....

Offline Biker Mike

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Re: Fork oil Refresh with a slight Modification.
« Reply #24 on: 16 August, 2016, 08:20:31 PM »
*Originally Posted by Markytp [+]
Silly question that I'm surprised hasn't been asked before........

Why don't we do a poll of things / jobs we would like to learn to do, then all chip in, pay Robo for a weekend of his time and we all meet up and have a weekend of "How to.....", a few sherberts, food and a bloody good laugh??  :001:
There's always this:
https://www.cbf1000.com/index.php?action=articles;cat=1

Offline Markytp

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Re: Fork oil Refresh with a slight Modification.
« Reply #25 on: 16 August, 2016, 08:23:26 PM »
*Originally Posted by Biker Mike [+]

Yup, there is that, but much prefer the craic of a meet, a few beers and some good grub than sat at the kitchen table in me underkecks reading off a screen.  :001:
2013 BMW R1200GS Adventure with all the toys.

Offline J-man

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Re: Fork oil Refresh with a slight Modification.
« Reply #26 on: 17 August, 2016, 06:32:43 AM »
http://www.racetech.com/page/title/Suspension%20Bible
Really cuts trough a lot of issues involved but it requires some study time while they came to a ton of effort to make it addressable for the mortal soul. This is the basics covered in a way you cant find it better Imho.

Offline alan sh

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Re: Fork oil Refresh with a slight Modification.
« Reply #27 on: 17 August, 2016, 08:50:30 AM »
*Originally Posted by Markytp [+]
Silly question that I'm surprised hasn't been asked before........

Why don't we do a poll of things / jobs we would like to learn to do, then all chip in, pay Robo for a weekend of his time and we all meet up and have a weekend of "How to.....", a few sherberts, food and a bloody good laugh??  :001:

Because he lives f'in miles away from me  :430:
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https://mybikinghistory.wordpress.com/

Offline SaturnV

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Re: Fork oil Refresh with a slight Modification.
« Reply #28 on: 17 August, 2016, 09:25:48 AM »
Good job Robo  :152:

Looks like you also resprayed the corroded fork ends while you had it apart??  Need to do that on mine too  :087:

Offline Markytp

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Re: Fork oil Refresh with a slight Modification.
« Reply #29 on: 17 August, 2016, 07:39:13 PM »
*Originally Posted by alan sh [+]
Because he lives f'in miles away from me  :430:

He's already said he'll travel if we cover diesel costs  :028:
2013 BMW R1200GS Adventure with all the toys.