Rough Shifting

For some reason many guys neglect clutch bleeding and leave the old DOT4 brake fluid in the clutch hydraulic system year after year. Eventually, corrosion and absorbing water will damage the CSC leading to shifting problems. Neglecting the brake fluid in the ST's brake system will gum up the secondary master cylinder in a shorter period of time than damaging the CSC...which might be why the clutch gets short shrift :biggrin: .
 
I think your right about the fluid neglect, The conditions the slave cylinder is exposed to with hot then cold and damp is a horrible exposure level. As well as the bleeder is at the top of the cylinder.
 
The bleeder needs to be at the top. The problem is that the inlet line is also at the top instead of at the bottom. If the bleeder was anywhere but at the top bleeding would not be very effective at removing the air.
 
Andrew Shadow said:
The introduction of hydraulic clutches are what made it possible to overcome the higher spring forces required of clutches needed for heavier motorcycles with larger displacement high torque engines. Without them there would be the need for ridiculously long lever throw and/or the need to have forearms like Popeye.
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There were lots of large displacement bikes with cable clutches over the years, Goldwings didn't have hydraulic until 1984, and there were numerous 900s/1000s/1100s with cable clutches in the day. However, engines were getting more powerful over time, and large touring bikes were getting heavier, so it was probably inevitable that cable operated systems would be replaced by something more powerful.

Another advantage of hydraulics is they are self-adjusting for wear, rather than having to periodically adjust the slack in the cable.
 
Beajae said:
Thank you all for the responses. It does appear to me that it is an issue with the clutch not disengaging completely. I did previously replace and bleed the fluid as it was pretty dirty and slightly low. Since I changed it, the fluid level has stayed the same. The linkage seems to be pretty smooth operating, but I will clean it all up and lubricate it just to be sure. The clutch lever does seem to be a bit loose so I will definitely take that all apart and check the bushing. And I did just change the oil. Unfortunately, its looking like I may end up having to replace the slave cylinder, as it did have a small leak so there is probably some corrosion in the cylinder. Good to hear its not my riding abilities. The link to how to replace the cylinder didn't work but I can just do a search. Lastly, does anyone have a source for a replacement slave cylinder and gasket.
Thanks again.
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Hi again @Beajae:

The best sources for parts would be: Partzilla.com, Discount Honda Parts and lastly, your friendly local Honda dealer (which will likely be expensive and require a back order). Here is the relevant page from the Partzilla,com website showing the CSC which attaches just to the left of the oil filter. This job is much easier if you remove the oil filter first BTW.

The clutch slave is part #3 (the assembly has a little box drawn around it) and it is in stock at a cost of $86 and the gasket is also in stock and costs around $4.68:
1760622199790.png
3CYLINDER ASSY., CLUTCH SLAVE
22860-MCS-000
In Stock		$111.23
$85.89
4GASKET, SLAVE CYLINDER
22862-MGJ-D00
In Stock		$6.07
$4.63

Also - you will need several (I'd get about a dozen of them) copper crush washers for the banjo fittings. Do NOT reuse the old ones - they might leak and are cheap and easily available.

Pete
 
MaxPete said:
Hi again @Beajae:

The best sources for parts would be: Partzilla.com, Discount Honda Parts and lastly, your friendly local Honda dealer (which will likely be expensive and require a back order). Here is the relevant page from the Partzilla,com website showing the CSC which attaches just to the left of the oil filter. This job is much easier if you remove the oil filter first BTW.

The clutch slave is part #3 (the assembly has a little box drawn around it) and it is in stock at a cost of $86 and the gasket is also in stock and costs around $4.68:
1760622199790.png
3CYLINDER ASSY., CLUTCH SLAVE
22860-MCS-000
In Stock		$111.23
$85.89
4GASKET, SLAVE CYLINDER
22862-MGJ-D00
In Stock		$6.07
$4.63

Also - you will need several (I'd get about a dozen of them) copper crush washers for the banjo fittings. Do NOT reuse the old ones - they might leak and are cheap and easily available.

Pete
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Thanks Pete. Already have the parts rdered.
 
motornut said:
Air does rise doesn't it
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Of course, which is why the bleeder needs to be at the top.
motornut said:
I think your right about the fluid neglect, The conditions the slave cylinder is exposed to with hot then cold and damp is a horrible exposure level. As well as the bleeder is at the top of the cylinder.
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Including As well as the bleeder is at the top of the cylinder in a statement that is detailing factors believed to contribute to slave cylinder failures gave me the impression that the bleeder's location at the top of the cylinder was also being considered a contributing factor. I was pointing out that it needs to be located at the top to be effective. The same is not true of the inlet. Having the inlet at the top contributes to ineffective flushing and it would allow that process to be more effective if the inlet was at the bottom.

If I have misunderstood and this statement was not intended to be included as one of the contributing factors listed, when taken as a separate and stand-alone statement its message eludes me.
 
Not even offended, I think that even if the hose was attached at the bottom the fluid would channel to the top when bleeding it. I think that periodically it needs to be disassembled and cleaned.
Although bleeding (flushing) makes those intervals extended a lot and is part of maintenance.
The fluid being hydroscopic, the slave cylinder being where it is, all of it together makes it something that needs to be monitored.
Most motorcycles don't load the mileage like the ST owners do, so they take a pass on the difficulties that are frequently seen by us.
Most of the bikes I see are in the back of the garage and working towards the back side of the lean to in back at a third of the mileage we see as normal, then become hand me downs to the younger relatives.
 
The fluid entering at the bottom and traveling through the cylinder to the exit at the top is why it would be more efficient at flushing the system. The fluid would have to flow through the cylinder and exit at the top carrying more of the old fluid and contaminants with it. The way it is designed with both the inlet and outlet at the top the fluid flows in the top and travels over to the bleeder right beside it and out without displacing very much of the old fluid or carrying out very much of the contaminants with it. Having the inlet at the bottom wouldn't be a cure all by any means but it would at least allow a better flush to be done.
 
- thread bump -

I seem to be having the same rough shift issue, going between 1-2 and 2-1

Clutch fluid looks new & clear, level is to the top of the window mark when the bars are turned to the right.

No leaks at the slave cylinder

Engine oil looks ok, about 3000 miles on it

Have not inspected the shifter linkage.

Any thoughts or recommendations?
 
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discoganya said:
Clutch fluid looks new & clear
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Do you know when the last flush was? If not, most would suggest doing one, so you're sure when it was last done.

Fluid in the master cylinder can look a lot different than fluid in the system as there's not a lot of swapping going on during activation in either the brake or clutch systems; the fluid doing the work is already in place except for the upper part interacting with the master piston. One recommendation is regular flushes (which reminds me, I still need to do mine this winter!) Take a look at what comes out vs what's in the master and let us know if you see anything different between the two.
 
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discoganya said:
- thread bump -

I seem to be having the same rough shift issue, going between 1-2 and 2-1

Clutch fluid looks new & clear, level is to the top of the window mark when the bars are turned to the right.

No leaks at the slave cylinder

Engine oil looks ok, about 3000 miles on it

Have not inspected the shifter linkage.

Any thoughts or recommendations?
Click to expand...
I had the same issue, cleaning and re-lubing the shift linkage fixed the problem. Since the bike is new to me, I also noticed that there is a decent amount of "play" for the shift lever before it actually changes the gear, so "preloading" the shifter helps as well.
 
discoganya said:
Thanks, what does that mean exactly? Push down twice, kinda like the trigger button on a camera?
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Apply upward or downward* pressure** to the shift pedal in advance of making a shift. When you are ready to pull the clutch lever and make the shift you increase the pressure to the amount that you would normally use to effect a shift.

* Upward or downward dependent on whether you are up-shifting or down-shifting.
** Enough pressure to engage the shifter mechanism without causing an unintended shift or forcing the linkage. Every motorcycle will react a little differently so a little experimentation is needed to determine what level of preload works best for you if it helps at all.

This is a procedure more commonly used for up-shifting than down-shifting, and one that you will need to try to see if it yields any benefits to you.

I would recommend first making sure that there is not something wrong with the shifter linkage, clutch hydraulic system, clutch, etc., before I would adopt a change in shifting protocol that may cover up an existing defect.
 
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