Someone in CHCH to make fork spacers

[Les]

I'm going to try some fork spacers in my 2003 SV650 (crap springs, dives a lot, etc. and can't afford a proper upgrade ) and was wondering if anybody could recommend a CHCH outfit who could manufacture some for me, or anyone here who can make them for me (for which I'll pay for, naturally)? I've posted on the SVDownunder website to get the dimensions, etc., so just gathering info at this early stage. Cheers.

[Robert Taylor]

I'm going to try some fork spacers in my 2003 SV650 (crap springs, dives a lot, etc. and can't afford a proper upgrade ) and was wondering if anybody could recommend a CHCH outfit who could manufacture some for me, or anyone here who can make them for me (for which I'll pay for, naturally)? I've posted on the SVDownunder website to get the dimensions, etc., so just gathering info at this early stage. Cheers.

Overpreloading of oversoft springs delivers an overly bad result. It will make them harsh at the top of the stroke due to too much pre-energy, but they will still act like oversoft springs when you ride over something abrupt!

They will top out too readily when accelerating off tighter corners in lower gears, reducing or even losing mechanical grip. Further. so much preload increases internal friction because the springs are rubbing harder against the internal wall of the fork tubes.

I accept that this is costly and that you cannot afford to upgrade correctly. This is just one of many reasons why I have so much contempt for a system that underpays and overtaxes the average Kiwi!

[FROSTY:Me]

Dude slightly longer spacers arent very vard to make--its only tube cut to lenth.
Ignoring all the reasons not to do it I'd lift the front of the bike up and undoo ONE fork cap and remove a spacer. You wont believe how uncomplicated they are and how easy they are to make.
Another option worth concidering is to see if your local wrecker has some springs that are slightly longer and slightly heavier wire.

[Robert Taylor]

Dude slightly longer spacers arent very vard to make--its only tube cut to lenth.
Ignoring all the reasons not to do it I'd lift the front of the bike up and undoo ONE fork cap and remove a spacer. You wont believe how uncomplicated they are and how easy they are to make.
Another option worth concidering is to see if your local wrecker has some springs that are slightly longer and slightly heavier wire.

And this is exactly the bad HEATH ROBINSON advice you should NOT be following. HECK, there is probably also no reason for the preload spacer tubes to be cut square in the book of ''Experts for all seasons and all the wrong reasons''.

Whilst agreeably sourcing some second hand springs in appropriate dimensions and rate from a wrecker is okay advice, in practice the chances of being sold something that is correct is akin to winning the big prize in lotto.

We always fit MUCH SHORTER springs that still have the required stroke integrity, in conjunction with much longer spacer tubes, squared off at each end in a lathe. This ( primarily )to minimise the number of coil sides rubbing against the inner walls of the fork tubes.

You have been given correct advice from a base of knowledge, training and experience. You have also been given some dodgy advice. It is your call.

[NZsarge]

Overpreloading of oversoft springs delivers
I accept that this is costly and that you cannot afford to upgrade correctly. This is just one of many reasons why I have so much contempt for a system that underpays and overtaxes the average Kiwi!

Here here....well said!

[laRIKin]

What I have done is cut the spring and this makes it stiffer and make a longer spacer and the pre-load can stay the same.

And that is if it is your spring that is to soft/weak for you and not something else.

I have done this and it works.

This is shown on the rear spring, but it is basically the same for the front.
And because there are more coils it is harder to get it wrong.
http://dirtbike.off-road.com/dirtbik....jsp?id=332656

You could go see Linton at Dirt Action and he will do it for you.

If you are keen to do it your self.
You will need this part to work out want you have and help you know how much to cut.
http://www.kreuzotter.de/english/efeder.htm (Helical Spring: Calculator just past 1/2 way down the page)

This site and others can give you an idea what spring rating you should be aiming for.
http://www.racetech.com/

One step at a time and it is best to start soft and work up to the harder setting as it is hard to uncut the spring.

I work at a Plumbing firm so may be able to find pipe you can use as a spacer, I use Fusatherm plastic pipe as it has a thick wall and is strong.

It may well be frowned on.
But if you are on a budget, it works fine.
I did it slowly, that is a few coils at the start to get it close and one coil at a time after that and the third time I was happy.

I think you should not rush in to cutting to much and let the springs settle between cutting's.

This may help as well.
http://www.strappe.com/suspension.html
http://www.ntnoa.org/suspension_preload.htm

[Robert Taylor]

What I have done is cut the spring and this makes it stiffer and make a longer spacer and the pre-load can stay the same.

And that is if it is your spring that is to soft/weak for you and not something else.

I have done this and it works.

This is shown on the rear spring, but it is basically the same for the front.
And because there are more coils it is harder to get it wrong.
http://dirtbike.off-road.com/dirtbik....jsp?id=332656

You could go see Linton at Dirt Action and we will do it for you.

If you are keen to do it your self.
You will need this part to work out want you have and help you know how much to cut.
http://www.kreuzotter.de/english/efeder.htm (Helical Spring: Calculator just past 1/2 way down the page)

This site and others can give you an idea what spring rating you should be aiming for.
http://www.racetech.com/

One step at a time and it is best to start soft and work up to the harder setting as it is hard to uncut the spring.

I work at a Plumbing firm so may be able to find pipe you can use as a spacer, I use Fusatherm plastic pipe as it has a thick wall and is strong.

It may well be frowned on.
But if you are on a budget, it works fine.
I did it slowly, that is a few coils at the start to get it close and one coil at a time after that and the third time I was happy.

I think you should not rush in to cutting to much and let the springs settle between cutting's.

This may help as well.
http://www.strappe.com/suspension.html
http://www.ntnoa.org/suspension_preload.htm

For those of us who like to do things properly this is indeed frowned upon and used as an absolute last resort only. Especially when suitable springs and precut spacers are available at ( in real terms ) pretty realistic prices.

So its a choice of a straight no hassle drop in or being prepared to laboriously mess around, with no guarantee that the result will be as good as it should be.

Cutting spring ends square is something that many people struggle to achieve, especially as I have even witnessed dealer efforts at failing to even cut preload spacers square! The cut ends of manually shortened springs are never a ''complete'' seating surface as per original. And even if they are only very very slightly off square that initiates internal spring rubbing somewhat sooner than it should.

It is surprising how little need to be cut off the coils to significantly increase the rate. Whilst calculus is available to determine the new rate there are variables, also dependent on how pedantic the person involved is at measuring accurately. If the springs are progressive in rate that throws in another variable....

Every time you shorten the spring that requires another set of preload spacers made. Thats okay if you have heaps of time and patience...

The theory is always fine until you try and apply in practice, many will have patience and diligence, many wont. You have to weigh that up.

Maybe better to work those hours you would otherwise expend to save money to do the job properly.

A good thing I think that many posts I have randomnly viewed are ( most hopefully ) not from people that work on aircraft.

[laRIKin]

To be honest Robert, if you said anything else I would have been surprised.

And you are right, but it can been done and MY time cost me nothing and I have the gear to do it, so it cost me nothing to do it, apart from fork oil.
So I do.

The only reason I answered is because Les said in his first post.

"can't afford a proper upgrade"

PS:
I wrote:
"You could go see Linton at Dirt Action and we will do it for you."

It should of said:
"You could go see Linton at Dirt Action and he will do it for you.

As I do not work there.

Now where is that other bit of number 8 wire?

[laRIKin]

Well after a lot searching I found this.
A fork spring work sheet.

http://motorcycleinfo.calsci.com/Sus...aseForkSprings

I new I had it some where.

And this in one of the site I have already posted.
http://www.strappe.com/spring_rate.html

[Robert Taylor]

To be honest Robert, if you said anything else I would have been surprised.

And you are right, but it can been done and MY time cost me nothing and I have the gear to do it, so it cost me nothing to do it, apart from fork oil.
So I do.

The only reason I answered is because Les said in his first post.

"can't afford a proper upgrade"

PS:
I wrote:
"You could go see Linton at Dirt Action and we will do it for you."

It should of said:
"You could go see Linton at Dirt Action and he will do it for you.

As I do not work there.

Now where is that other bit of number 8 wire?

It was never in dispute that it cant be done, what is in dispute is the very real quality problems that can and do occur.

That said, you have presented an infinitely more credible post than the first reply to this thread. It does concern me that people will ( very often ) all too readily accept ''Heath Robinson'' advice because of the limitations of their pockets. I think that also there is an historical ''kiwi can do'' mentality, too often in real terms actually meaning ''kiwi can bodge''.

I accept that too many peoples pockets are indeed less than bottomless. The sad reason for that is this country is sliding further and further away in real earning power and therefore expendable income. Our taxes are supporting fat living civil servants and politicians in Wellington, of ALL ''persuasions'' These bastards are stealing from us and creating such situations as this. Little wonder 747 people are leaving NZ EVERY week for Australia, or 100 per day. Bloody wonderful....

[Robert Taylor]

It was never in dispute that it cant be done, what is in dispute is the very real quality problems that can and do occur.

That said, you have presented an infinitely more credible post than the first reply to this thread. It does concern me that people will ( very often ) all too readily accept ''Heath Robinson'' advice because of the limitations of their pockets. I think that also there is an historical ''kiwi can do'' mentality, too often in real terms actually meaning ''kiwi can bodge''.

I accept that too many peoples pockets are indeed less than bottomless. The sad reason for that is this country is sliding further and further away in real earning power and therefore expendable income. Our taxes are supporting fat living civil servants and politicians in Wellington, of ALL ''persuasions'' These bastards are stealing from us and creating such situations as this. Little wonder 747 people are leaving NZ EVERY week for Australia, or 100 per day. Bloody wonderful....

Sorry, an embarrassing mistake and I fall on my sword. I should have said ''an infinitely more credible post than the SECOND reply to this thread

[F5 Dave]

. . .
I accept that too many peoples pockets are indeed less than bottomless. The sad reason for that is this country is sliding further and further away in real earning power and therefore expendable income. Our taxes are supporting fat living civil servants and politicians in Wellington, of ALL ''persuasions'' These bastards are stealing from us and creating such situations as this. Little wonder 747 people are leaving NZ EVERY week for Australia, or 100 per day. Bloody wonderful....

While we are both in rant mode I would like to suggest that a lot of the economic slide is to do with the increasing 'needs' of the average person. Apparently we all 'need' to have a cellphone, 'need' to eat takeaways, 'need' sky connection and a million other things our parents somehow frittered their meaningless existence away without.

[Les]

Thanks everybody for an interesting discussion. For sure my preferable option is to put some more suitable springs in there, and I must admit that I haven't even seriously researched that option re. price etc. I could fit them myself anyway. So, any suggestions for new springs for a potential "proper upgrade"? I was keen to try running some small spacers and a heavier oil at a slightly higher level to see how that would work. I have done this mod before to an XT600 that I had and it worked good with reduced dive under braking and firmer "low deflection" springing due to a smaller air volume.

I'm no scientist (but am an NZCE qualified engineer) but I'm definitely NOT interested in bodging something to an unsafe degree, especially since I'd be astride the machine in question! However, I do fully appreciate the qualified comments that have been put forward from people who appear to know a whole lot more about these things than me. Thank you. It's interesting your comments Robert re. these people fixing aircraft, 'cos that's exactly what I do for a living. I do generally prefer the "correct" solution, but you would possibly be surprised how much of an imperfect discipline aero engineering can actually be...

Thanks again everyone, and keep the comments coming!

[F5 Dave]

...
Thanks agai everyone, and keep the comments coming!

ok.

You 'need' to have some stiffer fork springs & maybe a valve kit as well.

So there you have permission

[FROSTY:Me]

Actually Im sick of this shit Robert.
At NO point did I suggest cutting SPRINGS nor did I suggest the tubing be cut by hand or off square.
In what way is this "Heath Robinson??"

MY advice was a plagerisation of advice given to me by people who are actually building and RACING Sv650's both in the united states and the UK and have been doing so for several years.