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Old 04-18-2013, 09:27 AM   #766
SOLO LOBO OP
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Quote:
Originally Posted by naginalf View Post
but will close by asking if you, Solo, having worked so hard to know your airhead inside and out, can honestly say that you are comfortable not knowing ANYTHING about the inside of your forks?
I am also fine with not knowing how to rebuild my transmission, and head reconditioning, final drive re-shimming, and a number of other things where I feel like spending the $$ to have a specialist do the job right the first time is worth it to me.
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Quote:
Originally Posted by Stagehand
your bike is suitably dirty. Well done.
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Old 04-18-2013, 01:44 PM   #767
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This thread has legs again!
Good points guys, it is an interesting discussion and probably quite an old and beaten out one regarding suspension tuning, shim stacks and the interwebs- we aint going to solve it so there is not point in trying.
I hope we are not dissuading Alex from joining the discussion.


I'll also be shipping things to various places to get some specialist work done that I can't do myself (or don't want to try to learn to do- at least yet)- transmission rebuild, head, piston and cylinder porting, recondition and machining, etc. These are 'do it once right' jobs IMO and ones I am not set up to do- and yes, they are paying for the result not a lesson in how to get there- and very importantly I know exactly where and who I will be sending these to.

For some reason I think of suspension tuning a little differently, not that it is less specialist or anything, nor that it is any less result-oriented, but that it is something that I would rather have done locally or alternatively (with some outside help if possible) take it on as something to learn enough to do it myself.
Not to learn how to be a suspension tuner, but from a given starting point just to learn just enough to start to tweak this one fork on this one bike towards desired outcomes. I think there is a significant difference there.

In the hands of the right expert, the shimming and springing work might be a do it once kind of thing, but the maintenence is ongoing and there are internal wear/replacement parts so I will be in and out of my forks anyway.
If this was a proven application (say for a newish bike that is produced and sold in the many thousands), where a given tuner had done it all before and knew exactly the ground being covered then I might believe it more of a do it once and do it right kind of job- that is if I could find the right tuner... I haven't been able to and from the people I have spoken to if they even agreed to begin discussing taking on the job it seems to be more of a 'we'll just have to start trying things and keep at it until you are happy (or broke) and the results are probably not going to be good' quite a sales pitch.
I found one helpful fellow about 500Km's away who was willing to work on this. I would have to bring the complete running bike to him. He wanted to respring it using off-the-shelf springs from 4860 forks (that by reports rattle around in our forks). He was a seat of the pants guy rather than a dyno guy, and shim stack changes would be tested by actually riding the bike, and though I got the feeling he would be able to improve the forks a lot the sheer logistics of getting this done were insurmountable to me.

For us, compared to the USA, we get significantly screwed with shipping costs, and one certainly doesn't want to be shipping forks (or anything else big and heavy) back and forward across the country or internationally for ongoing tweaks, thus if I have to go down the path of paying some one to do this for me, I would like to be able to drive/ride within an hour or two and actually see them face to face. I deal with a lot of things that might potentially require ongoing service or warranty type stuff this way.

I woud happily buy internationally, with no guarrantees, for a shim kit to get me started. I would happily pay a decent premium for this and for the knowledge it takes to be able to offer such a thing. I would expect this would only be a starting point and would in no way come close to actually handing over the forks or complete bike to the right person. It was the sniff of this possibility a few pages back that got me interested again.

Completely aside from that I just want to hear a pro talk a little or a lot about these forks for this application. Knowing a few of us, and what we have invested in them so far, we'll probably be stuck with them for the next decade or two and by that time the next crop of suspension tuners REALLY won't want to touch them
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Old 04-18-2013, 01:53 PM   #768
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On a related note, there is a set of WP Extreme 50mm's for sale in the flea market right now.... this is the complete kit with forks, triples, axle, wheel, rotor, caliper and master cylinder.

What's cool about these is that they are the earliest version that came on the 1998 620 Adventure's.

http://advrider.com/forums/showthread.php?t=879514
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Quote:
Originally Posted by Stagehand
your bike is suitably dirty. Well done.
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Old 04-18-2013, 02:14 PM   #769
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Quote:
Originally Posted by naginalf View Post
I'm not arguing about the value of the services. The service is very valuable, and I'm willing to pay the price. I'm willing to pay for advice and tips, whatever the cost. But don't give me this horse poo that I can't tell a bad shim from a good one. I'm sure in motocross, knowing the intricate details is important, but we just want general stuff, not the deep dark secrets he has worked so hard for.
Its not only telling a good shim from a bad one. Recognizing what the fork does or does not do is one of the most difficult things. Learn to feel what your damping system is doing when you push a fork one by one with your hand.

The details that you might think only motocross guys need to know might make all the difference for our airheads for road and off road use.

I have been to a few of those suspension classes and it was surprising to see prof racers, life long bike mechanics or MX champions struggling with suspension even with all their experiences.
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Old 04-18-2013, 02:16 PM   #770
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Look what Alex just delivered to me at my office!

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Quote:
Originally Posted by Stagehand
your bike is suitably dirty. Well done.
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Old 04-18-2013, 02:18 PM   #771
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They look perfectly valved and sprung.
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Old 04-18-2013, 02:22 PM   #772
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Quote:
Originally Posted by Airhead Wrangler View Post
They look perfectly valved and sprung.
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Quote:
Originally Posted by Stagehand
your bike is suitably dirty. Well done.
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Old 04-20-2013, 01:14 PM   #773
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Quote:
Originally Posted by Stagehand
your bike is suitably dirty. Well done.

SOLO LOBO screwed with this post 04-21-2013 at 07:15 AM
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Old 04-20-2013, 01:33 PM   #774
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well......did you ride the damn thing???
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Old 04-20-2013, 02:09 PM   #775
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Originally Posted by hardwaregrrl View Post
well......did you ride the damn thing???
Sadly no time today!
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Quote:
Originally Posted by Stagehand
your bike is suitably dirty. Well done.
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Old 04-20-2013, 02:14 PM   #776
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Quote:
Originally Posted by SOLO LOBO View Post
Sadly no time today!
as a quick summary in the meantime:

how much did you cut off the fork length ? Is that a standard length monolever ?

I am sure the info is in the depths of this thread, so apologies
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Old 04-20-2013, 02:23 PM   #777
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I have a set of these forks and they are around 4 inches longer that stock do they shorten them or just run them a few inches higher in the triple clamps?
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Old 04-20-2013, 03:33 PM   #778
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Looking sexy Solo,
how do you like the gaiters? Do you feel you have enough room to compress them- mine feel like they will limit suspension travel- but then I can't slide them down the fork legs due to my fork brace.
Ras and Waco,
here is Solo's buried post dealing with the fork shortening,
and a brief one by me after,
yes they are shortened- very simple to do.

Quote:
Originally Posted by SOLO LOBO View Post
OK, Let's get busy with the fork strip... this is all done following the instructions from the Husaberg WP Extreme manual linked on the first page.

Remove the top:


Here are the innards, the black plastic tube is a 3.5" spacer that I will be removing from the comp side, and replacing with a different spacer on the rebound side to limit the fully extended length. This will be a temporary measure to make the forks similar in length to the stop forks until I extend the swing arm and go back to full length. I haven't made any calculation and haven't planned on changing the springs and valving... I will only be shortening the length to do some testing.


And the correct order and orientation of those bits:


610 mL's drained from the tube:


Oops, the lower washer that is below the spring fell out while draining the forks the manual is very specific that the orientation of this washer should be carefully noted!


So here are all the bits:


Next, remove the lower bolt to release the damper. I used the axle to hold the leg while removing the bolt.


Extract the damper mechanism


See that aluminum wheel at the top? It has to be unthreaded to allow access to the return spring where the new extension limiting spacer is going to go... the manual shows this fancy tool that I don't have and am not going to buy.

The first attempt to make a adjustable pin spanner involved an old crescent wrench and two drill bits, stolen from last month's Classic Bike magazine:




After dulling and sharpening a number of bits, a number of times and not making any headway (use, I used copious oil to cool the bit) I changed it up and used an old rear shock spanner


That quickly bent


I didn't want to clamp the tube in the vice, so here is what I did, I ended up using another c-clamp on the other end of the screwdriver with a small block of wood to hold everything in place


Version three... another shock spanner, but twice as thick as the version 2 version


That with some heat did the trick! The spacer is going to go below that spring and will reduce to total length the forks can extend to.


So, now I need two sections of tube that have an OD less than 21mm (edit - 20.0mm to 20.3mm fits well, closer to 21mm does not) and an ID larger than 12mm. The closest thing I could find at the local hardware store is 1/2" schedule 40 pipe. It is a starting ID of ~15.3mm and an OD of ~21.4mm


Now, I am trying to figure out the easiest way to turn down the OD of the schd 40 to 21mm without a lathe.... more later need to eat some lunch.


Quote:
Originally Posted by ontic View Post

First I set about shortening my forks.
Nothing new to show here that Solo hasn't already. Thanks to his write up and PM's it was pretty easy. I have shortened them by the full length of that black spacer. I'm not sure if this is exactly spot on for G/S measurements, but it feels pretty close.

here are the 'special tools' I improvised.
Protaper bar risers with two layers of leather around the cartridge tubes and clamped in the woodworking vice.



worked great.

next, that damn triple pin thing- I just found some rollers from an old needle bearing from my 4x4 that fitted perfectly and then a couple of vice grips and some heat applied around the thread, and it turned and cracked the the thread easily enough.




Some time soon I'll have to go to the trouble to actually make that special tool- I just didn't have the patience tonight (as it is going to have to be a pretty good fit to work well). At the least, next time I'll find my other set of vice grips so that I can use three pins instead of two.

Not much different here to Solo aside from the colour of the PVC pipe I used for my new spacers. Well, they are KTM forks aren't they
As you can see, new spacer same length as the black spacer that is being removed.





Did both forks, put it all back together, and we now have a much shorter front end- suddenly the side and center stands work again.
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Old 04-21-2013, 07:18 AM   #779
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Quote:
Originally Posted by ontic View Post
Looking sexy Solo,
how do you like the gaiters? Do you feel you have enough room to compress them- mine feel like they will limit suspension travel- but then I can't slide them down the fork legs due to my fork brace.
Ras and Waco,
here is Solo's buried post dealing with the fork shortening,
and a brief one by me after,
yes they are shortened- very simple to do.
Thanks Ontic for the shortening info...

I have my boots pushed about 10-12cm below the fork slider tops, so no issues with limiting the travel.
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Quote:
Originally Posted by Stagehand
your bike is suitably dirty. Well done.
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Old 04-24-2013, 08:12 AM   #780
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Added six gallons to my almost empty tank and rode in today ~15 miles.

My initial impressions are.... WOW!

It's much better (thanks Alex !)

Compliant, planted, firm and feel right about where they need to be. Previously they were bouncy, a bit weird.

For sure I need to adjust my rear shock as I had backed off the comp and rebound to compensate for the forks... I need to add some comp back in for sure to start.

I did hit every pot hole from home to work but there's no dirt between here and there. Now I need to get out ride more miles.
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Quote:
Originally Posted by Stagehand
your bike is suitably dirty. Well done.
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