Tank Slap - Motorcycle Forum

This is the TSR item Duke.

If I knew it would fix things I would buy it but could be an expensive trinket if the problem still exists.

http://m.ebay.com/itm?itemId=271375911626" onclick="window.open(this.href);return false;

Can't find any info on stroke for either Brembo or OEM master cylinder and searched for ages as wanted to check this before the purchase.

Brembo do recommend there mc and others sp2 owners have the same set up with no problems so assuming it's OK.

I changed the springs as originals were worn about 50% (but still within service limit). The new ones are OEM Honda but have 1 mm longer free length as obviously new and not worn.

I'm wondering if this extra preload is the problem as the slave cylinder is weak / worn so can't over come it fully but could just over come it with the old worn springs. Fitted.

Did you try running the bike before changing the clutch springs, Blade?

The tolerances between a clutch working or not are very very small. All my knowledge is Ducati based but i know some run their clutches with some springs missing to reduce the effort required at the lever. Its possible your new springs are too strong and stopping the clutch rod releasing the clutch plates either due to wear or because there is insufficient force in the clutch hydraulics to push the rod far enough out.

I don't know what is easiest to try first but do one thing at a time and test again.

Just to add i popped into the garage and did a quick check on how far my pressure plate moves with full clutch lever actuation and i reckon its about 1.5mm, 2mm at max.

^ thats why a small spacer might make a difference

Cheers for checking the travel Duke really good, useful info and very much appreciated.

I will try the actuation with original springs and see what difference that makes. I think I'm definitely leaning towards too much spring preload or weak slave cylinder now rather than air in the system. Could be a combination of both.

Thanks again mate.

Perkles wrote:^ thats why a small spacer might make a difference

Yes I agree Perkles only problem is I haven't got access to a spacer.

I think changing the slave cylinders seals and spring will possibly have the same effect as if the spring is too weak the piston won't be touching the push rod at the start of clutch lever pull and therefore wasting travel closing the gap before contact is made with the push rod.

It's frustrating that I can't try some of these ideas and have to wait until not minding my youngest.

Gaffer tape the kid to the garage wall. That's one problem solved.

Haha don't give me idea's

Blade wrote:Haha don't give me idea's

Never too young to start training helpers.. Even better if they can read numbers, that way they can get the right spanners for you

He's actual quite good at taking things apart its just most people would see it more as good at breaking things

Just spoke to Neil Spalding and he was very helpful.

He reckons its trapped air and says it can be a real pita to get rid off. Sometimes they remove all the kit and hang it vertically of the bike for days and try to get the air to move upwards and then bleed at the high point.

looks like tomorrow could be a full day of bleeding

Blade wrote:Just spoke to Neil Spalding and he was very helpful.

He reckons its trapped air and says it can be a real pita to get rid off. Sometimes they remove all the kit and hang it vertically of the bike for days and try to get the air to move upwards and then bleed at the high point.

looks like tomorrow could be a full day of bleeding

why dont you buy an easy bleed kit they are cheap as chips

I have just read your original post again, Blade. If your clutch slave only moves .7mm then your problem has to be somewhere between the new RCS And the end of the clutch slave actuator.

Is the RCS below the level of the new Rizoma reservoir? If so it be worth removing the clip on and leave the RCS above the level of the reservoir overnight.

Duke I'm obviously being thick but why would that help ?

Perkles wrote:

Blade wrote:Just spoke to Neil Spalding and he was very helpful.

He reckons its trapped air and says it can be a real pita to get rid off. Sometimes they remove all the kit and hang it vertically of the bike for days and try to get the air to move upwards and then bleed at the high point.

looks like tomorrow could be a full day of bleeding

why dont you buy an easy bleed kit they are cheap as chips

Got a recommendation as a lot of cheap rubbish about as with most things.

Blade wrote:Duke I'm obviously being thick but why would that help ?

Because if the air is trapped between the RCS and the new reservoir, then if you put the lever above the reservoir the air will automatically rise to the top of the RCS and be easier to remove.

edit: or maybe it's me being thick.

If you want a vacuum kit, Blade then i would go for either this one http://www.amazon.co.uk/Sealey-Vacuum-T ... grid_i_0_0

or a Mityvac http://www.amazon.co.uk/MITYVAC-MV8000- ... ds=mityvac.

I have got a Mityvac and my own honest opinion is they are great for drawing new fluid through the system but not any better ( and probably not even as good) for bleeding the system.

Okay made some progress tonight in the fact the bike now goes in gear but not 100% sure everything is perfect so want to do some more tests tomorrow.

After discussing things with Neil Spalding the suggestion was its air in the system so I have bled the entire system again but cannot get any more travel at the clutch plate still 0.7 mm possibly 0.8 mm being optimistic. As I'm 99.9% confident all the air is removed and when the clutch lever is pulled in I can rotate the clutch centre by hand I thought maybe that's all the travel that should exist so I thought lets give it a go,

I started the bike and thought just go for it and try and get her in 1 st gear The good result is the bike now goes into first gear and if I'm totally honest perhaps always did its just when I heard the clunking noise I originally backed off.

However I'm still not convinced everything is 100% correct as A, the bike makes a loud clunking noise when entering 1st gear which I cannot remember it doing previously and B, the clutch bite point is very immediate now as in just out from the lever fully pulled in.

Any suggestions or theorys are welcome or I will just carry on tomorrow and hopefully road test.