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I am new to my 2000 rc and was wondering if it is normal for these bikes to have the clutch engage at the very far end of the lever travel. I bleed the system and cant seem to change it...thanks
 

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If you are absolutely sure that there's no air in the system and still the lever engages far from the grip, apart from adjusting your lever to wherever work better for you, you should open the clutch cover, take out the friction and metal clutch disks and measure them for recommended thickness according to the Service Manual.

Would also be very good is you took the clutch's slave cylinder apart and check the piston and it's seal for wear.
 

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If you are absolutely sure that there's no air in the system and still the lever engages far from the grip, apart from adjusting your lever to wherever work better for you, you should open the clutch cover, take out the friction and metal clutch disks and measure them for recommended thickness according to the Service Manual.

Would also be very good is you took the clutch's slave cylinder apart and check the piston and it's seal for wear.
Being a 2000, this is sage advice the clutch could be at the end of its service limit. As well, the clutch master cylinder has a spring and rubber parts that deteriorate with age.

This isn't bad news just turning out to be more maintenance that you may have expected.:cool:
 

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I recently changed my slave cylinder's seal kit & piston and the improvement was dramatic.

I had installed new OEM friction and metal plates in the engine back in 2008 when I bought the bike and they have been used for 25.000km so far with no signs of wear at all.
 

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Nature of the beast with a hydraulic clutch.
Play with it all you want. It's self adjusting so you'll end up where you started.
Plates might be worn.
Air will give opposite effect because it acts like spring in itself.
SP2 judder spring will give more feel & is the best way forward.
Conversion to cable is the ultimate improvement without a doubt.
 

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I haven't tried cable & feel no need to, but if the clutch system is working correctly it should be adjustable to have clutch bike earlier if you want it. I've fitted a larger bore M/C and it releases earlier still, with plenty of disengagement for finding neutral, etc. when I want.
 

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You can only adjust where the lever sits on the mount relative to the master cylinder, same as your brakes?
You don't adjust your brake lever to compensate for pad wear do you.
So hydraulic systems are self adjusting.

Larger bore M/C will displace more fluid. I'de expect that to give less feel unless the pivot is shorter.
 

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Yes, that's right, but it also means the clutch releases less if you adjust the lever so it's closer to the grip - which in effect means it'll bite earlier as there's less release.
 

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Yes, that's right, but it also means the clutch releases less if you adjust the lever so it's closer to the grip - which in effect means it'll bite earlier as there's less release.
No shit Sherlock!

I think the point here is the feel when engaging/disengaging the clutch.
The majority of this is countering the force the clutch springs are exerting on the plates. As soon as the force on the release bearing is the same as the springs, then the clutch is effectively released.
Nothing has moved at this point. Just applied pressure.
Fluid is non compressable so doesnt contribute to "feel" the same way a cable does. As a cable will stretch slightly as it's tensioned.
This ignores the effect of the oil in the multiplate system. But it does back up the theory of fitting the judder spring fitted to the SP2.
 

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pbc0, I appreciate you've developed a cable operated system for the RC51 from parts off a Honda Varadero and feel that for you it's the best solution, but l think there's no need to go into how a hydraulic clutch system works compared to a cable operated one, unless we really want to compare the pros and cons of them...(I guess it might be interesting to, though - so I'll discuss below)?

What I'm saying is that there's nothing really so bad about the standard SP2 hydraulic clutch if it's in good working order. At least I never felt anything wrong with mine over a period of 7 years. It didn't grab too early, nor late or feel as if it needed improvement. Perhaps SP1's are different? - I don't know as I've never ridden one. Perhaps someone else can chime in and let us know their thoughts on the SP1 system. :)

TBH I changed my clutch master only because a good used billet master came up at a good price the same time I bought my forks and it's looks would match my Brembo m/c better so I went for it. It's slightly larger bore and yes it requires slightly more effort to release the clutch as a result & yes the effect is reduced "feel" but even in traffic where I need to slip the clutch accurately I find it doesn't really bother me. I wouldn't have minded at all keeping the standard bore size either.

Personally I prefer a hydraulic clutch release system since it's less troublesome & requires less maintenance over the long term. I've had plenty of bikes over the years with cable operated clutches. Cables stretch over time, need lubrication and if the adjuster at the lever isn't properly set it can cause the cable to chaff and begin to break. If you ever run out of adjustment on a cable system (Because the cable wasn't 100% right to begin with) then it becomes another problem to resolve. Also the OEM lever mechanisms on cable clutch are of typically of lesser quality (They come from cheaper to manufacture bikes after all).

There are pros & cons to both types. Hydraulic system components combined are slightly heavier and may feel a little different at the lever, but generally they're smoother to use since there isn't the friction of a cable inside a sleeve and pistons inside cylinders are effectively always lubricated...

Let's look at the simpler form of brakes on a bike. Would you prefer the precision of a hydraulic system to operate the brakes over a cable operated one?
Me - I'd go for the hydraulic one every time. Because there's usually less "play" and less wasted effort.

For a clutch on every down change I'm pulling in the clutch lever and rev-matching, so why would I want to introduce play & added friction into the system when it would only make the system less efficient & quite probably more trouble prone?

I guess it comes down to preference. I daresay on a race bike where you're shedding the last few grams wherever possible a cable operated system may be preferable (& any decently prepared race bikes will tend to have a quick-shifter & slipper clutch), but on a road bike? With all things considered, I prefer hydraulic.

I think most owners would agree there's really no great need to change the original system as it works fine if in good working order (Makis' experience of changing the slave cylinder seals sounds like good advice). Like anything on a bike, poor maintenance can mean performance can be compromised that's all...it's not necessarily the reason to give up & change a system in it's entirety.
 

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I've lived with cable actuated clutches enough....they are PITA, IMO.

Since the bike's total weight isn't a crucial issue to me cause I don't race it, I'd go for the hydraulic actuated system every time even if that mean I had to add 2 pounds to the bike's total weight.

6 months ago, I helped a friend built a hydraulic actuated clutch on his GSX750R SRAD where Suzuki has a cable actuated clutch as the OEM setting......he still thanks for that!
 

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Shit man!
The precision wanted for braking is different to the feel required on a clutch.
RC723
It sounds like the hydraulic system on your bike is working good. The very short answer to your question is yes.
Air in the system will not result in the clutch releasing right at the end of lever travel. Unless your bike was built in a parallel universe where the laws of physics don't apply. Nor would a faulty slave cylinder.
Your plates might well be worn. But the problems experienced with the SP1 clutch are well documented on here.
I extolled the virtues of a cable clutch as a last resort. After the fitting of a judder spring.
If you are planning on keeping yor bike, upgrading the clutch with the SP2 judder spring is worthwhile. It only involves replacing the inner plate with a modded plate & a cup spring.
Honda call it a judder spring because that is what it counteracts. But it is actually just a counter spring acting a giants the clutch springs through the plates.
 

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Couldn't give a fiddlers fart for what type clutch actuation others use by the way.
Cable works for me & there's nothing wrong with hydraulic if that's your thing.
 

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Shit man!
The precision wanted for braking is different to the feel required on a clutch.
Look at how many modern bikes have clutches operated with a hydraulic system? Somehow I don't think engineers developing these things get it wrong.

Here's a famous race spec. RC51. Food for thought. :)

 

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Look at how many modern bikes have clutches operated with a hydraulic system? Somehow I don't think engineers developing these things get it wrong.

Here's a famous race spec. RC51. Food for thought. :)

Superbikes too



As well as MotoGP



I think I'll stick to the hydraulic for now :rolleyes:
 

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Don't see any with the SP master cylinder.
And there's plenty folk do like cable clutch.

So what's the advice for RC723 then?
If you think you've got to keep bleeding the clutch every time the clutch don't feel right, save yourself the hassle.

PUT A CABLE ON IT!

Or be a sheep & go with the herd.
 

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Assuming clutch plates aren't worn the easy solution is: Change the seals on the slave cylinder, take apart and clean both cylinders then bleed with fresh fluid, adjust the lever as necessary to get the biting point desired and have a clutch that works fine for years without need for further maintenance (just like all the other sheep - mmmmmeeeeehhhh! :D).



...Only this sheep chose to use a bike with a cable clutch! :D
 

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Don't see any with the SP master cylinder.
And there's plenty folk do like cable clutch.
:D :D :D Do you think cheap mass produced Honda master cylinders have any place on some of the most expensive HRC championship winning bikes made in their era?

Yeah, the sheep & her mate above probably like their agricultural cable clutch too. Don't take it too seriously, I'm just pulling your (4th) leg! :p :D:D:D
 

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I bleed the whole clutch system once a year, before the summer kick in and never ever had a problem with it.

I am going with the herd now.....
I probably bleed my clutch every couple of years or so, or when I see the fluid start to change from it's original colour (blue turning to green over time in my case).

Fluid is hydroscopic and eventually for bikes with very poor maintenance corrosion can start to form in cylinders (For my KMX200 which I bought at 20 years old with under 2,000km - which had been stopped for over a decade I used a dremmel with a brass brush to clean behind hydraulic seals for all the hydraulics and they have been working fine since). Usually corrosion is more likely in brake calipers where they're exposed to rain water during use - especially those without dust seals. SRAD GSXR's were notorious for corrosion in seals behind their calipers resulting in poor performance IIRC...

On another subject, but related - on cars I tend to bleed brakes with fresh high boiling point fluid before every trackday or where they'll be used hard, continuously since water collected hydroscopically in older fluid can boil and leave vapour instead of fluid in brakes under extreme conditions. TBH I've only ever seen this happen where people take their cars onto the circuit with very old brake fluid, then be told they were pumping furiously to get pressure back into they brakes at the end of a long straight. I've never seen brake fade on a bike yet because the caliper temperatures typically aren't as high as with car brakes - but then I wouldn't use old fluid on a bike's brakes either. :eek:).

Seals in a clutch slave probably age over the years due to heat... Hasn't been a problem in mine yet but I might change my seals next time. May as well... they're now 12 years old and have covered about 50,000 km of use. I don't think I've bled my clutch more than around 3 times during ownership, the last being when I fitted the new Brembo M/C.
 
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