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Discussion Starter #1
Hi fellas,
Anyone in the forum has the above dry clutch fixed on their bike?
I've got one fixed on my 2009 GT1000 and I have problems. The guy from Bursi is not very helpful and poor in response to email.
The clutch shifts up ok but runs into all sorts of trouble shifting down.
I) hard to find neutral
II) grabby and lever will suddenly lose pressure
III) gear engaged but bike won't run
IV) bike very snatchy on first gear
Hydraulics are fine, no air bubbles in the clutch line.
TIA and Appreciate it if someone can help.
 

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How long has it been installed and how many miles ridden on it?

Have you verified the correct clutch pack stack height and assembly order?

Have you tried bleeding the clutch slave manually to ensure there is no air pocket in the housing? (i.e., removing and forcing the piston in with slave body tilted forward so any trapped air will be forced out the bleeder at the back).

DO you have aftermarket levers fitted and if so, were they done around the same time and was the clutch lever free play checked?


If up shifting is fine than down shifting should be fine too. The clutch does not care what gear the bike is in. It should either grab, or not.


As for the low speed grabbyness, dry clutches aren't the smoothest as they do not have the oil bath lubrication a wet clutch does.
 

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Discussion Starter #4
Thanks for your reply Danbuc. i had a crash late 2014 so i changed a whole bunch of parts. i'll answer your questions in red

How long has it been installed and how many miles ridden on it? It was installed late 2015 and i think i've got about 1000km on it

Have you verified the correct clutch pack stack height and assembly order? I should think so it was done by a reputable mechanic who preps race bikes

Have you tried bleeding the clutch slave manually to ensure there is no air pocket in the housing? (i.e., removing and forcing the piston in with slave body tilted forward so any trapped air will be forced out the bleeder at the back). Yes this was done and there's good pressure on the lever

DO you have aftermarket levers fitted and if so, were they done around the same time and was the clutch lever free play checked? yes, it's one of the parts i have changed. i got 899 master cylinders on together with aftermarket slave cylinders with 30.5mm inner piston. clutch free play is good


If up shifting is fine than down shifting should be fine too. The clutch does not care what gear the bike is in. It should either grab, or not. this is puzzling to me. like it would be ok then suddenly it would grab or would not engage


As for the low speed grabbyness, dry clutches aren't the smoothest as they do not have the oil bath lubrication a wet clutch does. ok. something that i have to live with. i rode the monster s4r before and i don't remember it to be so jerky
appreciate your help.
 

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As for the low speed grabbyness, dry clutches aren't the smoothest as they do not have the oil bath lubrication a wet clutch does.
Not sure I understand that logic but my stock dry clutch feels fine to me. Same for the dry clutches on my cars.
 

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Air_Cooled_Nut, neither of the dry clutch ducs I have are nearly as smooth off the line as any wet clutch bikes I've ever ridden. They are smooth, but not as smooth as a wet clutch.



OP, did it start after the 899 master and aftermarket lever install install? Or did it just suddendly start happening out of the blue? The hydraulic system should be sealed, so if the lever suddenly just gets spongy or weird out of nowhere then there is either air entering the system, or the fluid is expanding and not being allowed to bleed off back into the reservoir because of insufficient free play in the lever blocking the bleed port.

Does it happen only once you've put a few miles on the bike and it's warmed up or does it happen even on cold start up?
 

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Discussion Starter #7
danbuc,
the 899 MC and dry clutch were installed at the same time. it usually happens after the bike has been running after a while. i don't think there's any air getting into the system.
what i did notice when i was bleeding the bike (bled in reverse first by pressing the piston on the slave cylinder to let the air out thru the MC reservoir, then bled thru the two nipples) that the piston was slow to return to the original position. is this a problem?
the dial on my clutch lever has been dialled in completely so the lever is extended to the max.
feels like there's a lot of free play but what do i know ;-)
 

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The free play in the lever is the amount it can move before acting on the piston. Its this slack that's needed to allow for fluid expansion when it gets hot.

If the slave piston is not reliably returning to it's original position then the D-cup seal may be failing (like when a brake caliper piston gets stuck).

Might be worth dismantling the slave cylinder and checking the piston, seal and bore for any wear to see if it's sticking or binding as well and give it a good clean.
 
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