'Gold valves'?

[gatch]

Are all gold valves the same ? If not what are the major differences ? the little springs on them would vary yes ? Port sizes ?

I ask because I have access to a pair (unsure of what bike they come from) and have considered trying to make my own to suit my forks (I'm sure they are showa ky6 - 89 honda spada).

Am I barking up completely the wrong tree or is this doable ? I've got a project I'm working on and I would like to fabricate as much of the bits I can as possible, mostly to keep the cost down..

Any help would be great.
Cheers
Gatch

[cowpoos]

You need to talk to Robert Taylor...

[CookMySock]

[...] have considered trying to make my own to suit my forks [....] Am I barking up completely the wrong tree or is this doable ?Do it. The technology is 50 years old, and is perfectly straight forward. Sure there are ultra modern versions of it, but a digressive valve is a digressive valve is a digressive valve.

I think you will have to buy the shims.

I found a NZ company making these valves some time ago. It occurred to me to write some CNC to make boxes of them for a dollar each, but someone else had done it already.

Steve

[gatch]

Do it. The technology is 50 years old, and is perfectly straight forward. Sure there are ultra modern versions of it, but a digressive valve is a digressive valve is a digressive valve.

I think you will have to buy the shims.

I found a NZ company making these valves some time ago. It occurred to me to write some CNC to make boxes of them for a dollar each, but someone else had done it already.

Steve

I don't know what the shims look like, although I have access to a surface grinder and a full catalog of drill sizes if need be.

[Pussy]

Are all gold valves the same ? If not what are the major differences ? the little springs on them would vary yes ? Port sizes ?

Yes, there are differing port sizes, diameters of units, spring preload tensions etc etc.
Cowpoos gives the best advice... talk to Robert Taylor. He knows about this sort of thing

[CookMySock]

I don't know what the shims look like, although I have access to a surface grinder and a full catalog of drill sizes if need be.A shim looks like a thin flexible round disc with a hole in it. It's made of the same sort of steel the fingers on a feeler gauge is. The steel is apparantly quite special.

Steve

[gatch]

Right on, depending on the thickness I could probably punch some out, we've got a bunch of different size shim stock I could pinch, fuck its good being an engineer huh..

In saying that it'd probably be easier to buy them..

[Robert Taylor]

8% or more of the world economy is piracy. And in NZ making a fair and reasonable profit is something that many frown upon. Having respect for intellectual property is also something that many dont take seriously.
Yes there are many different designs and whilst some of it may look simple there is more than meets the eye, especially with the settings. Send me an image of the set you are looking at to my regular e-mail address.

[gatch]

Guilt.. The worst kind of trip..

Will try get a photo of said valves, however if they are unsuitable I will probably ask more questions about your retail pricing. Despite the cost I would rather get it right first time than fuck around with a home built item that may or may not do the job..

[CookMySock]

8% or more of the world economy is piracy.Citroën cars had shim stack digressive suspension in 1954. My old Dad used to add and remove shims in his workshop 35 years ago. It was interesting telling him about Ohlins - he wandered off to his workshop and came back with a little digressive valve and asked "like this?" I wish I had taken a photo of it.

Search for the word "leaf" on this page - http://en.wikipedia.org/wiki/Hydropneumatic_suspension

Steve

[gatch]

Citroën cars had shim stack digressive suspension in 1954.

You mean the cv ?

[CookMySock]

You mean the cv ?Actually it looks like it was 1955. The <a href="http://en.wikipedia.org/wiki/Citroën_DS">DS</a> was the first car to fully utilise it. Dad had a number of them. Standard, they float around like a boat, but with a few extra shims in the shim stack, and a little more pressure in the spheres, and they went real good.

Steve

[gatch]

A dude that used to belong to our gun club had a cv, he'd charge in the gate at the rifle range and straight off the road across the paddock, I don't think a hover craft would have had a smoother ride across the grass.

You would have thought the boxes of ammo and various rifles would have flown all over the place, but no, safe as houses, safe as citreons in this case eh..

[CookMySock]

Yeah we used to scare hell out of people. Hitting traffic humps at about 90k/hr was our favourite. They nearly lept out the window, but nooooo the car flew over them without even a blink. We just looked at their white face and pissed ourselves laughing. Do that in a vehicle with progressive suspension and be prepared to launch into space.. :killingme

Steve

[Robert Taylor]

Yeah we used to scare hell out of people. Hitting traffic humps at about 90k/hr was our favourite. They nearly lept out the window, but nooooo the car flew over them without even a blink. We just looked at their white face and pissed ourselves laughing. Do that in a vehicle with progressive suspension and be prepared to launch into space.. :killingme

Steve

Yes indeed Citroen were very much the pioneers in this. Now 50 odd years on it rather proves a point that manufacture and performance owes more to price than it does to the fact that technology exists that would give us much better ride quality and control.
Because everything is price driven that is why we have so many makes and models with appallingly bad suspension.

[Robert Taylor]

Guilt.. The worst kind of trip..

Will try get a photo of said valves, however if they are unsuitable I will probably ask more questions about your retail pricing. Despite the cost I would rather get it right first time than fuck around with a home built item that may or may not do the job..

We do have a handful of kits at present at pre- increase prices.

[Robert Taylor]

Citroën cars had shim stack digressive suspension in 1954. My old Dad used to add and remove shims in his workshop 35 years ago. It was interesting telling him about Ohlins - he wandered off to his workshop and came back with a little digressive valve and asked "like this?" I wish I had taken a photo of it.

Search for the word "leaf" on this page - http://en.wikipedia.org/wiki/Hydropneumatic_suspension

Steve

Some digressivity is good, on bumpy ''g'' out surfaces you also often have to have a little progressivity to ''catch'' longer stroke movements to afford some decent pitch control.

[gatch]

We do have a handful of kits at present at pre- increase prices.

Excellent, I asked about getting hold of said valves and they have already been put back in the H2.. Probably could find something a little more suitable yes..

I'm not entirely certain about the model of fork on my spada as there is no stamps or stickers, working on it right now.. The rear however is showa ky6, height adjustable only, nitrogen filled.

[gatch]

I emailed showa support yesterday asking what model number fork was installed on the spada, haven't got a reply yet.

If they are hoping that by not replying to my correspondence I will give up they have another thing coming..

Edit - for some reason my email service reckons I am spamming showa with junk mail.. Bastards

[Robert Taylor]

are all gold valves the same ? If not what are the major differences ? The little springs on them would vary yes ? Port sizes ?

I ask because i have access to a pair (unsure of what bike they come from) and have considered trying to make my own to suit my forks (i'm sure they are showa ky6 - 89 honda spada).

Am i barking up completely the wrong tree or is this doable ? I've got a project i'm working on and i would like to fabricate as much of the bits i can as possible, mostly to keep the cost down..

Any help would be great.
Cheers
gatch

what is the exact model designation and engine capacity of that bike, all suffixes / prefixes etc?

[gatch]

89 honda spada, mc20, vt250j

engine capacity is 249cc

[Robert Taylor]

89 honda spada, mc20, vt250j

engine capacity is 249cc

99% that its damper rod type and therefore requires emulators, the size required can be determined by the od of the fork springs.
If it has no external adjusters and the initial feel is very ''mushy'' then its damper rod type, almost completely unlikely that a bike of that capacity and vintage has cartridges.

[gatch]

Yes sounds about right, the front end is about as solid as a water bed..

As its a one year only model its hard to find any relevant info, I have a service manual (and soon a book with part numbers hopefully) but at the moment I can't tell you any other numbers/figures.

[cowpoos]

99% that its damper rod type and therefore requires emulators, the size required can be determined by the od of the fork springs.
If it has no external adjusters and the initial feel is very ''mushy'' then its damper rod type, almost completely unlikely that a bike of that capacity and vintage has cartridges.
same diameter forks as a MC21 nsr

[gatch]

37mm sound about right ?

thats what my ruler and eye-ometer tell me

[Robert Taylor]

37mm sound about right ?

thats what my ruler and eye-ometer tell me

Remove one fork cap to expose the top of a spring and measure its outer diameter ( you can leave it in place so its not a big deal to do this )

[gatch]

righto, will do tomorrow, don't have the necessary 17mm hex key on hand..

The gold valve emulators are adjusted by a thread in the top of the unit yes ?
might have to turn up some new fork caps so I can fiddle with them externally..

[Shaun]

righto, will do tomorrow, don't have the necessary 17mm hex key on hand..

The gold valve emulators are adjusted by a thread in the top of the unit yes ?
Might have to turn up some new fork caps so i can fiddle with them externally..



no stop weight

[Robert Taylor]

righto, will do tomorrow, don't have the necessary 17mm hex key on hand..

The gold valve emulators are adjusted by a thread in the top of the unit yes ?
might have to turn up some new fork caps so I can fiddle with them externally..

Ok, but you cannot fiddle with them externally, that would take some very elaborate and clever engineering

[cs363]

righto, will do tomorrow, don't have the necessary 17mm hex key on hand..

The gold valve emulators are adjusted by a thread in the top of the unit yes ?
might have to turn up some new fork caps so I can fiddle with them externally..

No, you won't be able to adjust them externally as they sit on top of the damping rod, under the spring (see attached pic). That said if you are getting someone like RT to do the job and give him all the neccessary information about your bike, weight and riding style he has the knowledge to set them up for you. Once set up you shouldn't need to readjust them unless your habits change like perhaps going from road riding to hard out track use.
RT has done an emulator install and suspension tune on two of my bikes and I cannot speak highly enough about the work done, he's not the cheapest but his work is beyond repute - hence the Dr. Bob moniker he is often labelled with.
Bear in mind that to be totally effective you will ideally need to get the correct weight fork springs for your weight/riding style, though I'm sure he will explain all that to you.
One thing I can tell you is that you will not regret spending the money, particularly if you intend keeping the bike for some time.
Suspension tuning is the best bang for buck mod you can make to a bike in my book! :)

[cs363]

Ok, but you cannot fiddle with them externally, that would take some very elaborate and clever engineering

Bugger, slipped in before me I see Mr Taylor! :)

[gatch]

I'm not quite sure if I have the right idea here, does the emulator move in relation to the top of the forks once installed, if it does my plan is foiled..

[xwhatsit]

I'm not quite sure if I have the right idea here, does the emulator move in relation to the top of the forks once installed, if it does my plan is foiled..
Yes, it is indeed the replacement for your damper rod.

[cs363]

Yes, it is indeed the replacement for your damper rod.

Not quite right I'm afraid, it sits atop the original (modified) damper rod.
I trust you meant it replaces the function of the damper rod, rather than the damper rod itself?

[gatch]

Bear in mind that to be totally effective you will ideally need to get the correct weight fork springs for your weight/riding style
Suspension tuning is the best bang for buck mod you can make to a bike in my book! :)

yup gotcha, I've been reading everything I can find about suspension lately (have a looky at my blog to see why), the suspension tech threads on here have been a big help so far..

I don't know how relevant it is at this stage but I found a spring weight calculator that tells me .75kg/mm springs would be about right for the weight of my scoot when assembled..

[cs363]

I'm not quite sure if I have the right idea here, does the emulator move in relation to the top of the forks once installed, if it does my plan is foiled..

I guess it depends on your viewpoint but as the fork tube is fixed in the triple clamps I would describe it as moving with the staunchion (or fork lower). The emulators position is where the red blob is in the attached pic.

[cs363]

yup gotcha, I've been reading everything I can find about suspension lately (have a looky at my blog to see why), the suspension tech threads on here have been a big help so far..

I don't know how relevant it is at this stage but I found a spring weight calculator that tells me .75kg/mm springs would be about right for the weight of my scoot when assembled..

That sounds very light, how much do you weigh in Kg's without your riding gear? And what sort of riding are you doing? (e.g. commuting plus a bit of open road riding moderate to higher speeds etc.)

[gatch]

About 80-85kg with my gear (a guess), bike should be around 150-160kg when its done, tank holds only 12L..

The intention is to put it on the track..

[cs363]

About 80-85kg with my gear (a guess), bike should be around 150-160kg when its done, tank holds only 12L..

The intention is to put it on the track..


:) You must have mis-read me, I actually said without riding gear, but no worries.
Using Race Tech's spring rate calculator and using the bike as a early model VTR250 (as they don't list your particular bike) they recommend 0.85kg/mm springs which is closer to what I thought they would require. Admittedly the early VTR has smaller diameter forks than yours but the bike weight is similar and the dynamics would be similar.

Robert could obviously advise you more accurately (probably worth a PM if he doesn't poke his nose back into this thread) but I would think that is closer to your desired spring rate bearing the intended useage in mind.
There are also other factors like the spring preload and spring weight (they are changeable) on the emulators as well as fork oil level which will also have an effect on the final set up.

Of course then the next thing is the rear end..... :laugh:

[Robert Taylor]

:) You must have mis-read me, I actually said without riding gear, but no worries.
Using Race Tech's spring rate calculator and using the bike as a early model VTR250 (as they don't list your particular bike) they recommend 0.85kg/mm springs which is closer to what I thought they would require. Admittedly the early VTR has smaller diameter forks than yours but the bike weight is similar and the dynamics would be similar.

Robert could obviously advise you more accurately (probably worth a PM if he doesn't poke his nose back into this thread) but I would think that is closer to your desired spring rate bearing the intended useage in mind.
There are also other factors like the spring preload and spring weight (they are changeable) on the emulators as well as fork oil level which will also have an effect on the final set up.

Of course then the next thing is the rear end..... :laugh:


Also, dont be tempted to buy those dodgy Thai copies as you will end up horribly dissappointed. The poppet springs sack out, the low speed flow modulation is all wrong and sloppy and the material is alloy with only a veneer of anodising, so the spring rubbing is going to wear them out fast and send chards of alloy through the forks. The Race Tech emulators are a well proven and reliable piece of kit and we have different settings for road race application.

[gatch]

Rightio, I just got a spring out, measures in at 30mm, the windings aren't all the same, that means its a progressive rate spring yes ?

[cowpoos]

Rightio, I just got a spring out, measures in at 30mm, the windings aren't all the same, that means its a progressive rate spring yes ?
progressive yep! a linear spring might be a good upgrade [weight matched] while your doin the gold valves.

[gatch]

Yeah man thats what I was thinking, I've read over and over from people who are knowledgable on suspension and noone rates them too highly eh..

Haa as such I forsee myself being poor for a long time..

[cs363]

Yeah man thats what I was thinking, I've read over and over from people who are knowledgable on suspension and noone rates them too highly eh..

Haa as such I forsee myself being poor for a long time..


:lol: Poor...but happy! :D

[gatch]

:lol: Poor...but happy! :D

Can't put a price on happiness eh..

[gatch]

The fork springs measure in at 340mm long (30mm OD), I thought they would be longer for some reason..

Also there is a thin tube sitting on top of the spring, this is how the preload is set yes ? Longer tube more preload etc ?

[Robert Taylor]

The fork springs measure in at 340mm long (30mm OD), I thought they would be longer for some reason..

Also there is a thin tube sitting on top of the spring, this is how the preload is set yes ? Longer tube more preload etc ?

Yes there are emulators available and those are preload tubes. PM me for pricing.