Fox 40, Spring Removal/service- (knocking)

Matt- D8

Matt- D8

Likes Dirt
Hey All

A quick Service question. My 40s are expieriences knocking throughout there stoke ( travel). I am quite aware that is the spring in the left staunching/lower thats knocking/taping against the (inner) walls of the lowers/staunchings.
So first up removing the top cap is relativley easy just a ".... spanner size", do i have to watch for any "air born" springs or in the spring under relativley low "load". Plus does the spring simply slide out? or is there an attachnment on the bottom of the lowers?

Second segment- once the spring is out, i have heard of many way to stop this noise: wrapping in electrical tape, condom, heat shrink and finally a road tube.
It seamed most logical slide a road tube over the top, heaverly greased up ofcourse. What do you think?

Is there anything i should watch out for?

and re- installing- same simple process? do i have to re-aline the sping to a particular attachment point in the bottom of the left lower?

I know theres alot of questions, i would appreciate it if you could answer as many as possibe.

Cheers Matt
:cool:
 
chu

chu

Likes Bikes and Dirt
ok so yes it does sound liek it ill be your spring tapping against the side wall of the lowers. the spanner size is 32 mm from memory and it is better to use a socket so that it doesnt leave any marking on the cap. all you have to do is gently undo the top cap and compress the forks. ie. push them down 'slowly' and the spring and the spacers that are on top of it will come out and then just take the spring out and put it on a clean surface. but the fox spring should already have heat shrink on it in the first place unless you have put a new spring in it. i havent heard on anyone putting these other things around the spring (electrical tape, road tube, etc) but i would suggest doing the heat shrink because it is the way they come from factory and it will garuantee to slide easily. before you put the spring back in put some more fork oil on the spring so it has the same amount as before then it is just a simple process of reversing the steps. put spring in. put spacers in (do not have to be ligned up to my knowledge) and then finally put the top cap back on but make sure you slowly do it up because it is a very fine thread and you really dont want to cross thread it. also threading it slowly will make sure you dont scratch the top cap to much.

hope that helps
 
henryg

henryg

Likes Dirt
^^^ good discription. post up a photo of your blue coil drew.

I have 25mm diameter heatshrink, if youre really nice i could send you a 15cm or so length. make sure it will fit round youre coil tho or drew could you measure the diameter of your coil.

Also, as well as doing it up slowly, make sure you do not over tighten the top cap (relativly soft alloy). when i put one on in the past i just turned the socket with my hand (no lever/wrench) and it was lubed to the shit with fork oil. all this equals fuk all torque.

Edit: PM if interested.
 
Matt- D8

Matt- D8

Likes Dirt
Hey fellas, thanks for the info, and detailed description, i will have to have a look and see weather the sping has heat skrink on it or not for it is second hand, it may have had previous modifications. Being labelled as sheat skrink and previously used it, is it necessary to skrink it using a heat gun or is this simply used as a sleeve which covers the entire spring?

i'll keep you posted.

Cheers Matt
 
Tazed

Tazed

Likes Bikes and Dirt
+1 for the most typos and hardest to read posts I've come across on Farkin.
Who said school standards had slipped? :p
 
henryg

henryg

Likes Dirt
Matt- D8 said:
Hey fellas, thanks for the info, and detailed description, i will have to have a look and see weather the sping has heat skrink on it or not for it is second hand, it may have had previous modifications. Being labelled as sheat skrink and previously used it, is it necessary to skrink it using a heat gun or is this simply used as a sleeve which covers the entire spring?

i'll keep you posted.

Cheers Matt
Click to expand...
On the stock springs it has about 15cm in the centre of the spring covered in heatshrink (hence the offer). Yes it has to be shrunk, or it would just slip to the base of the spring. Best discription would be a photo of chu's coil... *hint*

Axela8 said:
+1 for the most typos and hardest to read posts I've come across on Farkin.
Who said school standards had slipped? :p
Click to expand...
Well all those typos and wasted schooling just got Matt a comprehensive answer to his question and the offer of free shit for his bike..

+1 for wasting farkin space, at least were achieving something.
 
Matt- D8

Matt- D8

Likes Dirt
henryg said:
On the stock springs it has about 15cm in the centre of the spring covered in heatshrink (hence the offer). Yes it has to be shrunk, or it would just slip to the base of the spring. Best discription would be a photo of chu's coil... *hint*



Well all those typos and wasted schooling just got Matt a comprehensive answer to his question and the offer of free shit for his bike..

+1 for wasting farkin space, at least were achieving something.
Click to expand...
haha quality responce, oh and i believe its a 30mm ( correct me if im wrong), i measured it up, however its a fairly dodgy measuring tool. Is there any particular reason why there is only 15cm of heat skrink at the centre of the coil, would it hurt to cover three quarters or so of the spring? and saying this, is it possible to be knocking on the other two segments of spring ( above and below the heat skrink)thats were my idear came from.

Plus a picture would be greatly appreciated.

cheers Matt:cool:
 
Tazed

Tazed

Likes Bikes and Dirt
henryg said:
On the stock springs it has about 15cm in the centre of the spring covered in heatshrink (hence the offer). Yes it has to be shrunk, or it would just slip to the base of the spring. Best discription would be a photo of chu's coil... *hint*



Well all those typos and wasted schooling just got Matt a comprehensive answer to his question and the offer of free shit for his bike..

+1 for wasting farkin space, at least were achieving something.
Click to expand...
Fair enough - I deserved that! Just stirring... :D

I actually read this thread because, back when I ran coil springs (I've only had air forks in the last few years), I used to do the very same thing - heat shrink the springs.
What I found, though, was that inner tubes broke down in the lubrication/open bath oil.
So I'd suggest heat shrink rather than tube.
The reason you do it in the middle of the spring, BTW, is because when the spring is compressed, it moves most in the centre of the spring (left/right, back/forth) and that's when it hits the inside of the stanchion.
Make the heat shrink about 1/3 the length of the spring, then cut it onto 3 sections and space them apart by several centimetres.
Heat shrink VERY lightly, jsut enough to hold them in place - you don't want them binding in between the coils.
 
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henryg

henryg

Likes Dirt
Axela8 said:
What I found, though, was that inner tubes broke down in the oil. So I'd suggest heat shrink rather than tube.
The reason you do it in the middle of the spring, BTW, is because when the spring is compressed, it moves most in the centre of the spring (left/right, back/forth) and that's when it hits the inside of the stanchion.
Click to expand...
Beat me to it.

I tried to put some of my heatshrink on the coils in my Marzocchi DJ II but it wasnt a large enough diameter, i had to stretch it too much and i couldnt get it on.

still if you think you can get 25mm onto your coils then your more than welcome.

Edit: about using tubes, to my knowledge 40's only have an oil bath in the non coil leg for damping. obviously there is lubrication in the coil leg but it is more like grease. may still break em down though.
 
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chu

chu

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Axela8 said:
+1 for the most typos and hardest to read posts I've come across on Farkin.
Who said school standards had slipped? :p
Click to expand...
+1 for your a douche bag. why would you say that to someone who is making a decent contribution to a thread unlike yourself. if i was having a dig at someone else for there spelling in this thread then that would be fair game or if someone was making a worthless post then it is alright. but to say it to someone who is try to help a fellow farker out just shows how shorter time your stay will be here on farkin.

henryg said:
On the stock springs it has about 15cm in the centre of the spring covered in heatshrink (hence the offer). Yes it has to be shrunk, or it would just slip to the base of the spring. Best discription would be a photo of chu's coil... *hint*



Well all those typos and wasted schooling just got Matt a comprehensive answer to his question and the offer of free shit for his bike..

+1 for wasting farkin space, at least were achieving something.
Click to expand...


there you go for a photo of my coil as where you can see the shrink wrap. hope your happy had to go out and take my fox 40's apart to get you that:p

+1 for henry for PM
 
Matt- D8

Matt- D8

Likes Dirt
no worrys, its alright i will just purchase some heatshrink at the local hobbie store.
Is is compleley necessary to cut the 1/3 spring length heat shrink tube into 3 even sections, my only concern is what if the knocking sections occur and the several centermetre gaps between eat heatshrink section?

Is there anything else i need to worry about?
Have you heard of a similar problem with any other forks or 40s in particular?
Plus if there is heat skrink on there and it seams in good condition then what do you reakon the problem could be? do you recommend heat shrinking more of the spring instead of the centre?

Cheers Matt
 
henryg

henryg

Likes Dirt
Matt- D8 said:
no worrys, its alright i will just purchase some heatshrink at the local hobbie store.
Is is compleley necessary to cut the 1/3 spring length heat shrink tube into 3 even sections, my only concern is what if the knocking sections occur and the several centermetre gaps between eat heatshrink section?

Is there anything else i need to worry about?
Have you heard of a similar problem with any other forks or 40s in particular?
Plus if there is heat skrink on there and it seams in good condition then what do you reakon the problem could be? do you recommend heat shrinking more of the spring instead of the centre?

Cheers Matt
Click to expand...
I have never heard of the three section technique, i have the same concerns about it as you.

I would double up the original section before doing the whole thing. might just be wearing through.
 
Matt- D8

Matt- D8

Likes Dirt
henryg said:
I have never heard of the three section technique, i have the same concerns about it as you.

I would double up the original section before doing the whole thing. might just be wearing through.
Click to expand...
No worrys thanks for clearing that up for me.

Im sure i may be able to see any wear marks on the spring so that could half the time of this service.

i will attempt this tomorrow.

Cheers for all your help!:cool:
 
henryg

henryg

Likes Dirt
when you do it make sure you get photos in case you have questions, itll make things alot easier.
 
Tazed

Tazed

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chu said:
+1 for your a douche bag. why would you say that to someone who is making a decent contribution to a thread unlike yourself. if i was having a dig at someone else for there spelling in this thread then that would be fair game or if someone was making a worthless post then it is alright. but to say it to someone who is try to help a fellow farker out just shows how shorter time your stay will be here on farkin.
Click to expand...
Thanks for supporting my initial point...!

There was nothing personal nor directed at any individual in my post, just a statement about quality the posts (spelling, grammar, etc, not content).
You're right, it didn't contribute - but neither did the bile and vitriol of the responses...
Point was, if a person is to read and understand the posts, they should be of a decent level of literacy, accidental typos aside.

Read my 2nd post (above, or many of my other posts on Farkin) and you might reconsider your point regarding contribution.

I'll leave it at that.
 
Tazed

Tazed

Likes Bikes and Dirt
Matt- D8 said:
...
Is is compleley necessary to cut the 1/3 spring length heat shrink tube into 3 even sections, my only concern is what if the knocking sections occur and the several centermetre gaps between eat heatshrink section?...
Click to expand...
No, it's not. The assumption the spring is only contacting in the middle of the spring's length may not always be the case, though.
There's always some variation in the wind, and I've seen some deflect much closer to the ends.
Just covers the possibility the spring is deflecting somewhere else along its length.
Either method will work, I'm sure, with trial and error.
 
bellto

bellto

Likes Dirt
might be to late but i use glad wrap and as you said heat it on, works as heat shrink but it is thinner and cheap and accesible, no doubt that heat shrink is better though but this system works well with my forks. and you can also do the entire length of the spring. but first i always rinse the glad wrap off in diesle to get any adhesives off it, just in case they have an adverse affect in the fork, also make sure it is done well so no little bits of wrap fall into the fork.



oh yeah and there is a 40ml oil bath in both side of fox 40 forks. you can make this more but not necesary, whenever i swap springs i alway change the oil because it is not much more work. the manual says to use 7.5w oil but i like sikolene rsf 10w, makes the forks smoother.
 
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