See the other thread, KS34. A friend with a K7 750 is having a similar problem. I suspect it is an alignment problem. Your average K6/K7 sem fiddy handles like a dream, especially with the mod Robert has come up withOriginally Posted by KS34
sem fiddy pilot
See the other thread, KS34. A friend with a K7 750 is having a similar problem. I suspect it is an alignment problem. Your average K6/K7 sem fiddy handles like a dream, especially with the mod Robert has come up with
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sem fiddy pilot
The modded cartridges have done about 5500km now. Another added bonus is showing up... markedly reduced front tyre wear. Mind you, if it is being kept in proper contact with the road, ie the suspension doing the work and not so much the tyre, it makes sense.
Waiting for Kendog to chime in with his impression of the mod...
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Eyes that shine burning red
I hated it.................Waiting for Kendog to chime in with his impression of the mod...
Cause it made me think about spending more money on my bike
If I had the money I would love to put Ohlins on my bike, it really did feel so confidence inspiring riding yours.
Damn you Mr Ohlins.
sem fiddy pilot
RT is fitting a slighly different valving spec in the Ohlins front end 750. I will report in the other thread when I get the forks back. Give RT a holler regarding the modified stock cartridges, Kendog. You know you want to...
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Forum whore
I thought it timely to bring this up again because we have recently done a lot of dyno work with 20mm fork cartridges. With these particular Showa type forks they use a bending shim stack mid valve, the paricular mix of components is also used in the current model CBR600RR. This technology works very well but as JD has correctly pointed out elsewhere you have to be very careful about pressure balance. Get it wrong and the forks readily cavitate, that means the pistons are passing through ''froth'' and there is no damping / delayed damping.
The K6 on GSXR600/750 is notorious for woefully fast high speed rebound damping and as we discovered today on our dyno so is the CBR600RR. The instinct of the rider/tuner is to close in the rebound clicker to as little as only 1/4 to 1/2 turn out to give it more return control. That delivers at least three very negative by products 1) you may get an increase in high speed rebound damping but you also get more low speed damping which you very definitely do not want 2) As the rebound bypass cross talks / flows both ways you also get an appreciable increase in compression damping which again you do not want 3) The forks cavitate like mad with very very pronounced hysterisis / damping delay.You not only see this on a dyno, you feel it when you bleed the fork and it just feels horrible on the road / track. It also screws tyres. ( 25mm cartridges are a lot less susceptible and more ''forgiving'' re this issue )
The only soultion is to revalve the cartridges so that the high speed rebound damping provides the appropriate amount of damping force and also allows the rebound clicker to operate within a window of around 2 to 2 and 1/2 turns out to prevent this hysterisis problem.
''Fully adjustable suspension'' ( via external clickers ) is as big a lie as ''I didnt sleep with that woman''
Weekend cruiser
A good informative post Robert, the external adjusters are also partially disabled by the increasing use by manufacturers of bleed holes in the pistons, the cavitation you see is visible witha crank dyno, imagine what it would be like if you could spike them as in real use with an EMA dyno.
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Yes Id love an electromagnetic or a hydraulic dyno but the market here is just not big enough to justify spending telephone numbers on such a piece of equipment. I hear what you are saying, indeed when you are hand bleeding the rods you can hand dyno / spike it to feel for cavitation. Its also interesting to evidence the variations in bleed hole sizes / slots for different makes and models.
The average owner / rider would be horrified to realise just how ineffective those ''fully adjustable'' ( bollocks! ) clickers are and how easy it is to introduce cavitation. There is so much deliberate misinformation out there it is unbelievable.
sem fiddy pilot
I've just been communicating with another KBer regarding this mod.
One of the symptoms of the stock shortcomings is a feeling of "vagueness" from the front when the forks become "unloaded" rapidly (say over a brow, or off camber or rapid change of direction), and a pattering effect on corrugated corners. These are caused, in MY opinion, by the weak high speed rebound.
The "Gassit Girl" mod fixes it! It is the same mod that Toot Toot had done to his K8 sem fiddy
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"vagueness" is putting it mildly. Felt like the front momentarily lost traction.!
Hardcore Biker
You got it in one
I fear the day technology will surpass our human interaction. The world will have a generation of idiots! ALBERT EINSTEIN
sem fiddy pilot
The above mod puts decent oil in the forks, too, dipshit.
We have found the 15 centistoke oil works great for a road application
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Well dropped my forks out and sent them off to RT last week for this mod.
...Holy crap! I wasn't expecting this much difference in the feel of the bike after putting them back in!
The 600 steers and holds its line so much better now.
Before sometimes the 600 would feel like it wanted to run wide if you weren't fully on the game or was going through a corner on a trailing or neutral throttle. Gassing it mid-corner would suddenly tighten its line.
But now after sending the forks off to CKT the 600 is transformed!
Responds and goes exactly where you point it and holds its line no matter what you do with the throttle. Exactly how I like it.
I wasn't expecting this relatively simple fork re-valve to address those issues. I thought that's just the way the bike is and/or was my lack of riding skills for a modern performance based bike.
Very pleased with the handling and the feel of the ride of my GSXR now.
sem fiddy pilot
Good one, dipshit.... I knew you'd be rapt!
Amazing, eh, how such a relatively inexpensive mod and some decent oil can make such a difference.
Annie is still VERY happy with the way the forks on her sem fiddy perform.
I've still got the "leave the bloody things alone" mandate to adhere to!
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Forum whore
Hell yeah.
I got the 600 with the idea of making a sweet handling bike.
Two bikes I had ridden in the past really made quite an impression on me because of the way they handled.
An RZ 350 that had lots of suspension work done on it. It was very easy to change direction on yet still very stable and sure footed. Great fun to ride!
And a friend's 998 S. Point it in any direction and it would hold its line, bumps or not. Sweet.
Now my 600 starting to feel like this.
Forum whore
Anywho... so how dependent is this rebound fork mod on the 5 wt Ohlins oil..???
If I was to get a fork oil change, would any 7.5 wt fork oil be still be within working range?
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