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Discussion Starter #1
I am about to move to a 15/42 sprocket setup and am a little confused about what to do with the clutch lever. Doesn’t seem to make sense to follow the workshop manual and ziplock it fully engaged when removing the slave. I would have thought this will fully extend the piston when the slave is disengaged from the shaft making the installation difficult, am I missing something here?
 

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the reason the manual says to zip tie it is to close the system. when the lever is pulled the ports to the reservoir are blocked. this means that the system is of fixed volume and the piston in the slave cylinder cannot move.

if you do not zip tie it, the piston in the slave will creep out (there's a spring inside that will push it out) and will draw fluid from the reservoir and potentially pull air into the system. this is the cause of all the "i changed sprockets and now much clutch doesn't work" posts. there are thousands of them because people didn't follow procedure.


to make installation easier, zip tie the lever, then crack the bleed nipple at the slave to bleed the pressure off. this will keep the piston in a resting position where it can't creep out, but it will also keep it at the retracted position, not the extended position, so putting the cover back on will be easy as you don't have to disengage the clutch with the cover going on.


then when you are done, before you release the lever, open the reservoir and carefully watch the level as you slowly release the lever. if the level goes too low simply top it up. (when you release the lever you must fill the master from the reservoir as the slave has been bled off)



simple as that really.
 

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Discussion Starter #3
Thank you Wibbly, this is the clearest explanation I have seen! There are a myriad of posts on this but none that I could find give a technical explanation. Do you have an opinion on the “Nicky” modification ?
 

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I think it's stupid. It's one of those things people do to say they've done it and put it on a mods list. It has nothing to do with Nicky Hayden anyway.

It's way easier to remove the cover to change sprockets. And you should remove the cover to clean inside anyway.
 

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Discussion Starter #7
the reason the manual says to zip tie it is to close the system. when the lever is pulled the ports to the reservoir are blocked. this means that the system is of fixed volume and the piston in the slave cylinder cannot move.

if you do not zip tie it, the piston in the slave will creep out (there's a spring inside that will push it out) and will draw fluid from the reservoir and potentially pull air into the system. this is the cause of all the "i changed sprockets and now much clutch doesn't work" posts. there are thousands of them because people didn't follow procedure.


to make installation easier, zip tie the lever, then crack the bleed nipple at the slave to bleed the pressure off. this will keep the piston in a resting position where it can't creep out, but it will also keep it at the retracted position, not the extended position, so putting the cover back on will be easy as you don't have to disengage the clutch with the cover going on.


then when you are done, before you release the lever, open the reservoir and carefully watch the level as you slowly release the lever. if the level goes too low simply top it up. (when you release the lever you must fill the master from the reservoir as the slave has been bled off)



simple as that really.
Hi Wibbly,
Apologies for being so anal but as part of my web surfing i came across a youtube video where no bleeding was done prior to the casing removal I asked the question as to why and have received this reply , does leaving the slave attached to the case change the need to bleed?
cheers
ps i think he is referring to the Rogue site
"@alan If you watch my video you see I only removed 2 of the 3 bolts holding the slave cylinder in place. What I generally did was remove the sprocket cover leaving the slave attached. Their was a little hydraulic (brake) fluid leakage but you have to bleed the system when its reassembled. I found this suggestion on the Roug RC51 forums and it worked. decompressing the cylinder is what was stated in the shop manual (I have one)"
 

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just remove the slave and cover together. you can leave the slave cylinder bolt that doesn't land on the perimeter of the cover.


if you bleed the pressure off (not bleed the whole system, just crack the bleeder at the slave after tying the lever to let the pressure off) then there is no force from the clutch springs against the slave during removal or installation.


the guy in the video did it wrong if there is any fluid exiting the system. you do not have to bleed after reassembly.


youtube is a cesspool of idiots trying to get attention. there are so many terrible how-tos on there. just like anywhere on the internet, people are free to say what they want, and unfortunately the loudest are often the ones we should pay not attention to.
 

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Discussion Starter #9
Thank you , there is as you say so much information out there most of it not peer reviewed and often containing a lot of "half truths" ---makes it difficult to get to the heart of the issue. I will be sticking to this site for advice from now on. YouTube has some use as you can view the topic, just need to be careful and cross reference to a reliable source ----like yourself!
 

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none of this is rocket science. you can do it any way you like.

i suggest taking the pressure off the system so you aren't disengaging the clutch when you put the cover back on. it makes things easier

honda says to tie the lever and then let the cover disengage the clutch because eliminates any messing around with the fluid.


either way is fine, but it IS important to close the system before you remove the slave. that's all.
 

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Discussion Starter #11
All done without much drama but the piston moved despite zipping and cracking which meant I had to open the slave bleeder to get the cover back on and a quick bleed to finish the job. Would like to know how to avoid this if I change sprockets again.
 

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Maybe you didn't open it long enough for the piston to fully retract. You didn't have to open it again you could have just used the cover bolts to disengage the clutch as you tighten them.
 

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Discussion Starter #13
Unfortunately the bolts would not reach in order to get them started until I opened the slave. Not too worry the bike feels great with the 15/41 ( not 42) setup and I have booked a track day at Phillip Island in September for its first serious tryout since getting it up and running
 

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I had a problem trying to change my front sprocket. All went as planned and was able to remove the front sprocket bolt without a problem. I loosened the adjustment at the back tire as much as possible and moved the tire as far as it would go. Unfortunately could not create enough "slack" in the chain to remove the 16 tooth front sprocket. The rear 180 size tire was hitting the swingarm. Considered letting air of out of the tire to provide a little more slack. Did not want to "break" the chain right now to make the swap. The chain also seemed too tight to remove the rear wheel and have not taken it off yet. I know this is probably a stupid question but will chain have to be "broken" to get the rear tire off? Even if I remove the rear axle bolt it looks like tire will still be hitting the swing arm making the removal difficult. I recently had the chain replaced at a repair facility. I also loosened the bleed valve to relieve the pressure on the clutch after zip-tying the lever but had a minor problem getting the clutch bolts to engage when putting it back together but was able to get that worked out.
 

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robert, this is how you do it.


put bike on rear stand, remove rear axle nut

slide axle out (not all the way out, only far enough out for the adjuster block to come out past the adjuster bolt)

push wheel forward

roll chain off



do what you have to do, then reverse the process.




i don't believe what you are describing is even possible (where there isn't enough room to remove the chain from a sprocket)


IF the shop really did set the wheel so far forward that you can't remove the chain from the rear sprocket, you'll have to remove the rear sprocket in situ and then work from there.
 

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Ok. Understood. I was surprised as well how close the tire was to the swingarm. A quick solution would be to "break" the chain but did not want to do that. After reading previous posts and watching videos on how simple this was supposed to be was surprised I had the problems I did. Lots of cussing and a few beers later just decided to leave the 16 tooth. I am out of town working for several days but may try that process of partially removing the rear axle when I get back. Thanks for your response and suggestions.
 
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