View Full Version : Ohlins FGK 132 Cartridges...GSX-R 600/750, K6/K7
Pussy
27th December 2007, 09:33
My sem fiddy got a you beaut Xmas present. Fitted the forks back in on Xmas eve, complete with a set of Ohlins cartridges. I have only done about 400km on them so far, and I'm very impressed. The damping reacts what feels like instantaneously, with very controlled action. RT valved the cartridges to a spec to suit me, as he has a lot of experience knowing what I like, and has pretty well hit the mark first off.
A characteristic that comes to the fore straight away is the response whilst leaned over. I have one off camber/rippled corner I like to use to try different settings, and the bike feels VERY planted on it. The spec RT has given me is a nice combination of being firm but not harsh.
More to follow, folks, going to go out and try them some more......
NZsarge
27th December 2007, 10:02
My sem fiddy got a you beaut Xmas present. Fitted the forks back in on Xmas eve, complete with a set of Ohlins cartridges. I have only done about 400km on them so far, and I'm very impressed. The damping reacts what feels like instantaneously, with very controlled action. RT valved the cartridges to a spec to suit me, as he has a lot of experience knowing what I like, and has pretty well hit the mark first off.
A characteristic that comes to the fore straight away is the response whilst leaned over. I have one off camber/rippled corner I like to use to try different settings, and the bike feels VERY planted on it. The spec RT has given me is a nice combination of being firm but not harsh.
More to follow, folks, going to go out and try them some more......
Interesting....particularly the bit about off camber corners...
Pussy
1st January 2008, 15:05
Done about 1700km on the new front end now. Excellent!! The valving characteristics of these Ohlins cartridges is primo. The forks are held further up the stroke than before. It's amazing how little travel is used to provide very comfortable but controlled damping. You can observe them reacting to each and every little irregularity. The front end is very confidence inspiring even for someone of my lower ability. More to follow.....
Toast
10th January 2008, 14:11
How much?
Pussy
10th January 2008, 14:39
How much?
Approx $2700, would be best to check with RT when he gets back from Phillip Island to confirm
Pussy
10th February 2008, 19:20
Bit of an update... to say that Robert Taylor is a bit pedantic is like saying Attilla the Hun was a bit of a naughty boy. When RT supplied and fitted the new cartridges, he set a valving spec to suit me. After approx 4000km on them now, I identified that the high speed rebound damping was now just a whisker slow (as opposed to stock cartridges, where it's a bit too fast). Not a huge issue at all, but just not quite 100%. Not good enough for Mr Taylor. Out come the forks and a drop off to the surgery. Robert has now done some subtle adjustments to the rebound stack of the Ohlins cartridges, with bloody awesome results. The already very compliant feel has improved more, and the feedback is great. Now I've just got to get myself more skills to realise the potential the bike has...
Pussy
17th February 2008, 21:21
Another update: Just been to Paeroa and back, a good mix of road surfaces to really feel what the forks are like now... BRILLIANT.
It's not a cheap modification, but if you want your K6-K7 GSX-R600/750 to feel absolutely sublime in the front end, I would really suggest getting hold of RT and be prepared to shell out some readys, and go for it.
I'm rapt... :yes:
Pussy
1st March 2008, 07:48
'Nother update: Rode over to Taupo 28/2, Moto TT trackday 29/2, and back to NP same evening. The front end is to me faultless. It is easily the best suspension I have ever ridden on. I haven't found a single road surface that makes me want for any further improvement in the forks' performance, and on the track the feeling of confidence in the front is primo. Now, just have to upskill self...... :confused:
NZsarge
1st March 2008, 09:58
'Nother update: Rode over to Taupo 28/2, Moto TT trackday 29/2, and back to NP same evening. The front end is to me faultless. It is easily the best suspension I have ever ridden on. I haven't found a single road surface that makes me want for any further improvement in the forks' performance, and on the track the feeling of confidence in the front is primo. Now, just have to upskill self...... :confused:
Wow, even though it's an expensive mod it sound to me to be worth the money.....if you have the money that is.:pinch:
Shaun
27th March 2008, 07:31
I Have a USED set, fully serviced by Robert Taylor! @ CKT
I want $2000 for them, can have them fitted for you, approx another $400
Pussy
14th May 2009, 17:55
Another update:
Have tried a few different internal settings on behalf of RT to come up with the ideal road setting.
I realise that the best you've ridden on is the best you know... but I reckon we've got the settings VERY good.
Robert modified the compression pistons for more sharp bump compliance ( I found a deficiency on one particularly gnarly pothole), so that is sorted.
Because these cartridges are made to very fine tolerances, there is very little internal friction within the cartridge. This has enabled me to run heavier springs without discomfort, with the advantage of later/heavier braking capability and not having fully compressed forks.
The bending shim stack mid-valve keeps the forks higher in the stroke whilst providing excellent comfort/feedback/control/compliance.
Soooo, you road riders, if you get the oppurtunity to get hold of a set of FGK cartridges for your bike... go for it!
There have been some great deals (eg. Tony OK has/had a set for sale for a blade, Choppa for the ZX10 etc), and it is a VERY worthwhile mod for a road bike.
RT and myself have done the hard work to develop road settings, so a call to RT will sort you. You'll be very happy with them!
Ascott
26th June 2009, 18:17
Have just ordered a set of these from R.T. today through my local Sweesuki dealer along with the ttx36 so no doubt will have the same set-up as you have sorted! will be about 3 weeks to arrive, will let you know the results!:soon:
Al
Pussy
26th June 2009, 18:19
You ain't going to be disappointed, Ascott!
JD Racing
27th June 2009, 16:00
Another update:
Because these cartridges are made to very fine tolerances, there is very little internal friction within the cartridge. This has enabled me to run heavier springs without discomfort, with the advantage of later/heavier braking capability and not having fully compressed forks.
So how much internal friction were your original cartridges contributing to the spring rate 0.25n/mm, 0.5n/mm? How did you verify that it was friction that was contributing to the overall spring rate of the fork?
Robert Taylor
27th June 2009, 18:30
So how much internal friction were your original cartridges contributing to the spring rate 0.25n/mm, 0.5n/mm? How did you verify that it was friction that was contributing to the overall spring rate of the fork?
Unscientifically but effectively. The standard cartridges have a lot of piston ring friction and will not ''drop'' so readily when fully extended, they also dont clock into the forks exactly on centreline. Re-engineerable yes but the 25mm Ohlins system is a total engineering package and we have road settings that are working really well. We modify the pistons and have our own extensively tested valving specs. I am happy to forward these to you in confidence if you have customers with these and wish to try something different.
Pussy has done an enormous amount of road testing with both stock and Ohlins cartridges for me over the years and is VERY fussy. His feedback has been proven to be on the money time and again when we have set other customers bikes up with his road settings. To that end I totally respect his judgement and he is very valuable to me in developing road settings for both stock and aftermarket cartridges.
Pussy
27th June 2009, 19:15
So how much internal friction were your original cartridges contributing to the spring rate 0.25n/mm, 0.5n/mm? How did you verify that it was friction that was contributing to the overall spring rate of the fork?
It's VERY noticeable even when statically bouncing on the forks.
With the latest compression valving spec, I've gone from .95 to 1.00 kg/mm springs, and am experiencing a superbly comfortable ride.
JD Racing
27th June 2009, 23:10
Unscientifically but effectively. The standard cartridges have a lot of piston ring friction and will not ''drop'' so readily when fully extended, they also dont clock into the forks exactly on centreline. Re-engineerable yes but the 25mm Ohlins system is a total engineering package and we have road settings that are working really well. We modify the pistons and have our own extensively tested valving specs. I am happy to forward these to you in confidence if you have customers with these and wish to try something different.
Pussy has done an enormous amount of road testing with both stock and Ohlins cartridges for me over the years and is VERY fussy. His feedback has been proven to be on the money time and again when we have set other customers bikes up with his road settings. To that end I totally respect his judgement and he is very valuable to me in developing road settings for both stock and aftermarket cartridges.
I've yet to see any standard GSXR600/750 rods that do not drop into the cartridge of their own accord and that's when they've been thoroughly cleaned to remove all lubrication. I've seen aftermarket piston kits whose piston bands stopped the rod dropping but not to the extent of adding 0.5kg spring force. An Ohlins rod will always drop into a cartridge easier because it's a far heavier assembly.
The biggest friction forces in a fork come from the bushes on the outer tubes, the friction associated with 41mm bushes, seals and dust seals is going to far outweigh that created by the cartridge. A fork fitted with an Ohlins cartridge kit should feel very different to a standard fork, as good as Pussy is, if he can push on the two forks and determine that the difference between the two forks is down to cartridge friction then you should have him on the payroll, the guy is a genious.
I'm interested in the fact that you constantly come across forks with off centre cartridges, is there a particular bike that suffers from this, how far out of they? Since I first read you say this I've been measuring for it and not found any.
I've tried threading piece a 10mm ground bar into the bottom of the base valve then rotated the cartridge in V blocks with a dial gauge on the ground bar, I get next to no runout. I've not found a good way yet to measure the concentricity of the centre of the cartridge relative to the outer tube. I tried a bore gauge between the stanchion and spring seat, but the spring seat being pressed tin is not ideal, and is not necessarily concentric to the inside of the cartridge.
I also machined a base valve holder to allow a long 10mm ground bar to be threaded into the top of it when the cartridge body is mounted in the fork. Measuring between the stanchion wall and rod is difficult due to the free play in the cartridge bush being amplified by the length of the rod, how do you measure the concentricity?
Pussy
27th June 2009, 23:58
I'm no genius, JD.
But I can pick cartridge friction.... and the FGK cartridges have next to none
suzuki21
28th June 2009, 03:15
I'm no genius, JD.
But I can pick cartridge friction.... and the FGK cartridges have next to none
Tried to get hold of you last weekend beatch to visit you and the other half that does more miles on a ike than you lol. You were obviously hammering your forks on some road!
Robert Taylor
28th June 2009, 16:43
I've yet to see any standard GSXR600/750 rods that do not drop into the cartridge of their own accord and that's when they've been thoroughly cleaned to remove all lubrication. I've seen aftermarket piston kits whose piston bands stopped the rod dropping but not to the extent of adding 0.5kg spring force. An Ohlins rod will always drop into a cartridge easier because it's a far heavier assembly.
The biggest friction forces in a fork come from the bushes on the outer tubes, the friction associated with 41mm bushes, seals and dust seals is going to far outweigh that created by the cartridge. A fork fitted with an Ohlins cartridge kit should feel very different to a standard fork, as good as Pussy is, if he can push on the two forks and determine that the difference between the two forks is down to cartridge friction then you should have him on the payroll, the guy is a genious.
I'm interested in the fact that you constantly come across forks with off centre cartridges, is there a particular bike that suffers from this, how far out of they? Since I first read you say this I've been measuring for it and not found any.
I've tried threading piece a 10mm ground bar into the bottom of the base valve then rotated the cartridge in V blocks with a dial gauge on the ground bar, I get next to no runout. I've not found a good way yet to measure the concentricity of the centre of the cartridge relative to the outer tube. I tried a bore gauge between the stanchion and spring seat, but the spring seat being pressed tin is not ideal, and is not necessarily concentric to the inside of the cartridge.
I also machined a base valve holder to allow a long 10mm ground bar to be threaded into the top of it when the cartridge body is mounted in the fork. Measuring between the stanchion wall and rod is difficult due to the free play in the cartridge bush being amplified by the length of the rod, how do you measure the concentricity?
Yes I totally agree that main bushing friction and especially main seal friction are the biggest single causes of friction. We are ( unashamedly ) incredibly pedantic about seal friction. We only use genuine seals on sportbikes as frankly all of the aftermarket seals ( that at least are in this market ) are very dissapointing. Some, like those terrible red coloured 3 lip ''All Bollocks" seals increase friction enormously and would likely wear off microscopically thin low friction fork coatings at a massively increased rate. And they have the temerity to market them as low friction seals!!!
We re-lube main and dust seals frequently with seal grease, especially after riding / racing in wet conditions. I dont need to tell you how seal drag increases enormously once they are ''dried out'' We also often put a 5mm long cut in the dust seals to relieve friction and are also very pedantic about fork alignment and front wheel installation. The indicator of stiction is of course measuring the the static sag in two ways, 1) pushing down on the forks and letting them settle back upwards and 2) Pulling up on the forks and letting them settle back downwards. Then seeing what the difference is in readings.
Pussy has a GSXR750 with the said Ohlins cartidges. His other half also has the same model GSXR750 with stock cartridges that we have carefully set up. We have pedantically followed all the processes described so we are not fooling ourselves and its as plain as day that the Ohlins equipped forks are smoother in action, from the standpoint of friction. Both bikes are using very slippery Ohlins fork oil.
When you compare the stock and Ohlins cartridges out of these bikes its also very plain, the stock cartridges feel ''rough'' in comparison. Sure the rod is heavier in the Ohlins cartridge but the tolerancing and concenticity is superb, the polished steel rod is very low friction and there is very little drag on the split ( rather than one piece ) piston ring. The machining in the piston ring groove is also barrelled and backcut to further minimise friction as the fork is deflected, its all in the detail.The very latest production has now gone to an alloy rod with a very very low friction coating.
We see not only many sportbike forks but also lower grade cartridge forks such as in Hornets, Bandits, FZ1 / 6 etc. Its not uncommon to lift the lid and spy non concentricity just with the naked eye. Of course we see this all the time with damper rod forks.
The worst sportbike example is GSXR1000 K1 through to about K5. We have seen up to 0.3mm runout on the cartridge top cap relative to turning the tube in v blocks. You dont need a dti to see that! These are terrible forks ( especially K1, K2 ) and can be improved immensely. Happily we can take away 80 to 90% of that lack of concentricity issue with some careful machining of the seperated components.
JD Racing
28th June 2009, 19:22
Yes I totally agree that main bushing friction and especially main seal friction are the biggest single causes of friction. We are ( unashamedly ) incredibly pedantic about seal friction. We only use genuine seals on sportbikes as frankly all of the aftermarket seals ( that at least are in this market ) are very dissapointing. Some, like those terrible red coloured 3 lip ''All Bollocks" seals increase friction enormously and would likely wear off microscopically thin low friction fork coatings at a massively increased rate. And they have the temerity to market them as low friction seals!!!
We re-lube main and dust seals frequently with seal grease, especially after riding / racing in wet conditions. I dont need to tell you how seal drag increases enormously once they are ''dried out'' We also often put a 5mm long cut in the dust seals to relieve friction and are also very pedantic about fork alignment and front wheel installation. The indicator of stiction is of course measuring the the static sag in two ways, 1) pushing down on the forks and letting them settle back upwards and 2) Pulling up on the forks and letting them settle back downwards. Then seeing what the difference is in readings.
Pussy has a GSXR750 with the said Ohlins cartidges. His other half also has the same model GSXR750 with stock cartridges that we have carefully set up. We have pedantically followed all the processes described so we are not fooling ourselves and its as plain as day that the Ohlins equipped forks are smoother in action, from the standpoint of friction. Both bikes are using very slippery Ohlins fork oil.
When you compare the stock and Ohlins cartridges out of these bikes its also very plain, the stock cartridges feel ''rough'' in comparison. Sure the rod is heavier in the Ohlins cartridge but the tolerancing and concenticity is superb, the polished steel rod is very low friction and there is very little drag on the split ( rather than one piece ) piston ring. The machining in the piston ring groove is also barrelled and backcut to further minimise friction as the fork is deflected, its all in the detail.The very latest production has now gone to an alloy rod with a very very low friction coating.
We see not only many sportbike forks but also lower grade cartridge forks such as in Hornets, Bandits, FZ1 / 6 etc. Its not uncommon to lift the lid and spy non concentricity just with the naked eye. Of course we see this all the time with damper rod forks.
The worst sportbike example is GSXR1000 K1 through to about K5. We have seen up to 0.3mm runout on the cartridge top cap relative to turning the tube in v blocks. You dont need a dti to see that! These are terrible forks ( especially K1, K2 ) and can be improved immensely. Happily we can take away 80 to 90% of that lack of concentricity issue with some careful machining of the seperated components.
I'm not for one second disputing that Ohlins cartridges are a superior build quality, what I am disputing is that Ohlins cartriges allow you to run 0.5kg stiffer springs. You seem to be suggesting that when you ride a bike with a 25mm cartridge and a 20mm cartridge you can completely filter out the differences in hydraulic action and determine that the differences between the two is down to the friction.
What I was trying to establish was the concentricity of the centre line of the cartridge bush relative to the centreline on the stanchion, the outside of the top cap could quite easily be 0.3mm out relative to the tube as many are unmachined die cast, it's only function being a spring seat, it doesn't need to be true. On the cartridges I've measured so far the bush centre line is concentric as is the base valve. If the machining of the fork foot is causing the lack of concentricity or angularity of the cartridge then there is nothing much you can do about that.
Robert Taylor
28th June 2009, 20:26
I'm not for one second disputing that Ohlins cartridges are a superior build quality, what I am disputing is that Ohlins cartriges allow you to run 0.5kg stiffer springs. You seem to be suggesting that when you ride a bike with a 25mm cartridge and a 20mm cartridge you can completely filter out the differences in hydraulic action and determine that the differences between the two is down to the friction.
What I was trying to establish was the concentricity of the centre line of the cartridge bush relative to the centreline on the stanchion, the outside of the top cap could quite easily be 0.3mm out relative to the tube as many are unmachined die cast, it's only function being a spring seat, it doesn't need to be true. On the cartridges I've measured so far the bush centre line is concentric as is the base valve. If the machining of the fork foot is causing the lack of concentricity or angularity of the cartridge then there is nothing much you can do about that.
Thats Pussys assertion which he seems to be happy with and its probably indeed stretching the point a little but I dont think for one moment there was any attempt on his part to define a hard and fast figure. He is very happy and I like happy customers.
Im not going to read through all this entire thread again in an attempt to split hairs nor am I going to lose a wink of sleep about it. But it would be my reasonable understanding if you reduce friction, all else being equal you could run more preload or an incremental change in spring rate and get away with it. Enough said.
To clarify further on that top cap its 0.3mm runout at the end of the body cap, thats less at the bush but nonetheless there is enough at the bush to significantly magnify friction.
And I totally disagree, spring seats should be as true as possible to end up being perpendicular to the centreline of the fork tube, otherwise you are creating further unwanted side thrust of the springs against the inner walls of the fork tube. Of course the Ohlins internal spring guide system ( also WP, Traxxion, K-Tech and most MX forks ) minimises that issue.
Pussy
28th June 2009, 21:43
RT and JD.... you guys have forgotten more than I'll know about the technicalities.
I can tell you both, though, that the present valving spec in my bike has allowed me to run heavier springs to give a characteristic that I like, and am very happy with.
And, JD, I have tried several specs in this machine
Ascott
2nd July 2009, 16:44
Just a couple of questions, Pussy, are these 25mm cartridges? and what sort of road riding do you do? without giving anything away, do you "push the envelope" you can pm me if you wish. I have got a three week wait, it's like forever! I am fizzing a bit believe me!
Al
Robert Taylor
2nd July 2009, 19:36
Just a couple of questions, Pussy, are these 25mm cartridges? and what sort of road riding do you do? without giving anything away, do you "push the envelope" you can pm me if you wish. I have got a three week wait, it's like forever! I am fizzing a bit believe me!
Al
Ill answer for Pussy, they are indeed 25mm and they have settings in them that we have spent a LOT of time developing. The bump compliance on the road is superb and when you push the envelope they are very composed / controlled, such as at a track day.
You wont be dissapointed!
robertydog
2nd July 2009, 19:38
Just a couple of questions, Pussy, are these 25mm cartridges? and what sort of road riding do you do? without giving anything away, do you "push the envelope" you can pm me if you wish. I have got a three week wait, it's like forever! I am fizzing a bit believe me!
Al
Crikey im having enough trouble keeping up with the gixxer:crybaby:
Pussy
2nd July 2009, 20:43
Ill answer for Pussy, they are indeed 25mm and they have settings in them that we have spent a LOT of time developing. The bump compliance on the road is superb and when you push the envelope they are very composed / controlled, such as at a track day.
You wont be dissapointed!
Answered by PM earlier, RT!
Ascott
3rd July 2009, 18:51
Thanks R.T. and Pussy, I'm sure I will be thrilled!
Alvin
Pussy
4th July 2009, 11:10
Thanks R.T. and Pussy, I'm sure I will be thrilled!
Alvin
No doubt about it!
Pussy
7th December 2009, 20:44
Another brief update...
I'm not getting ANYTHING changed as far as internal settings go in these cartridges.
I'm not a fast track rider by any stretch of the imagination, but today was at the Manfeild trackday where we used the entire track.
I tried several different lines on the long left hand sweeper on the extension part of the track. There is a roughish repair on this corner. No matter which part of the repair I rode over, the bike was 100% composed. It just felt awesome!
If you can stretch your budget, I would strongly recommend chucking a set of FGK 132s at your K6 onwards six hundy or sem fiddy....
Yankee Doodle Dandy
8th December 2009, 01:08
I've seen aftermarket piston kits whose piston bands stopped the rod dropping but not to the extent of adding 0.5kg spring force.
I have seen this too. I have also seen aftermarket piston kits that fit so loose I was afraid they would not seal.
I know of one factory level team that was having fork problems and after trying several different things he felt way too much fluid was bypassing the rebound valve assembly.
I wish someone would produce a rebound piston with an o-ring behind the piston band just like a shock piston. You would have to play around with the o-ring size, groove dimensions, and the band thickness to get it right but I think once everything was sorted you would have a good seal without any noticeable friction.
Robert Taylor
8th December 2009, 07:59
I have seen this too. I have also seen aftermarket piston kits that fit so loose I was afraid they would not seal.
I know of one factory level team that was having fork problems and after trying several different things he felt way too much fluid was bypassing the rebound valve assembly.
I wish someone would produce a rebound piston with an o-ring behind the piston band just like a shock piston. You would have to play around with the o-ring size, groove dimensions, and the band with to get it right but I think once everything was sorted you would have a good seal without any noticeable friction.
I think also that a lot of oem cartridge tubes are not exactly round and true...and then theres the issue of them often not sitting concentric to the centreline of the fork when locked into place. Sidethrust, uncontrolled bypass leakage etc.
This is one reason so many suspension proffessionals have a cynical view of self instal. The success of the job can be so dependent on attention to detail and ACTUALLY KNOWING what you are looking for. There are very pedantic people out there, there are also many that have the mechanical finesse of an elephant.
Toast
8th December 2009, 10:43
Just like to add my experience of this product to the thread: My R6 race bike has Ohlins FGK 25mm cartridges up front
Yeah they feel amazing and let me get away with ham-fisted murder, but it wasn’t until I came to sell the set of Metzeler Racetecs that had done about 90 laps of track duty (about 35 Manfeild and 55 Taupo) that really showed me how well they have been working:
The greatest degradation in tread depth that I could find was about 80% of brand spanking new!! That was on the left shoulder which Taupo hammers when you’re braking hard in to turn 1 and the corner on to the main straight
I’m not a super fast fella and am not pushing the absolute limits of bike or tyres, but got to within about 3% of 600cc lap record at Taupo so, and compared to my old bike where I was destroying fronts at a slightly slower pace there this tyre wear came as a rather pleasant surprise!
Obviously I’d better man up and start pushing the bike!
(Not wanting to blow the Ohlins trumpet too hard here but the TTX36 rear has kept the rear tyre in even better nick than the front during that time!)
Yankee Doodle Dandy
8th December 2009, 12:30
I think also that a lot of oem cartridge tubes are not exactly round and true...and then theres the issue of them often not sitting concentric to the centreline of the fork when locked into place. Sidethrust, uncontrolled bypass leakage etc.
This is one reason so many suspension proffessionals have a cynical view of self instal. The success of the job can be so dependent on attention to detail and ACTUALLY KNOWING what you are looking for. There are very pedantic people out there, there are also many that have the mechanical finesse of an elephant.
One of my FAVORITE things is to come across a thread in which someone wants get their forks valved and someone else tells them to buy such and such parts because it is easy and then proceeds to tell them "I didn't even have to take the forks all the way apart, I just left them on the bike and took the cartridges out". They only did part of the job.
Shaun
8th December 2009, 13:41
They only did part of the job.[/QUOTE]
Exactually mate, where does all the old rubbish go then:gob:
Robert Taylor
8th December 2009, 16:18
One of my FAVORITE things is to come across a thread in which someone wants get their forks valved and someone else tells them to buy such and such parts because it is easy and then proceeds to tell them "I didn't even have to take the forks all the way apart, I just left them on the bike and took the cartridges out". They only did part of the job.
Yes its amazing how many different perceptions there are of what is a good job!
Yankee Doodle Dandy
14th December 2009, 14:09
Yes its amazing how many different perceptions there are of what is a good job!
You know what they say, ignorance is bliss.
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