999 clutch problem
 

Hi can anybody help shed light on the following? I have a 999 biposta 2006 deepsump model and the clutch has no feel to it I.e it bites virtually when the clutch lever is fully out. I have read the various posts regarding 999 clutch woes and none of them seem to mention this problem. The clutch has not been bled to cause any air bubbles in the system. Can anybody help or suggest any solution to this problem.

When was the last time you checked the stack height?

If you take all of the clutch plates (friction and steel) and then measure them all together, you want around 38-39mm in total.

If yours measures less than that then you need a new set of clutch plates!

999 clutch problem
 

Thanks for your reply Antony’s, the clutch wear should be fine as the bike has only done 7.5k miles?

Not neccessarily! It all depends on setup, wear, use, etc.

Probably worth checking regardless!

Thanks for the advice I will strip the clutch and check the dimensions before I do anything else. Will let you know the outcome of the investigation when I have completed the task.

999 clutch problem
 

Just measured clutch stack height and they measure 38.3 to 38.4 so clutch plates are ok. Anybody have any other suggestions as to what the problem may be?

Now you know that the clutch stack height is ok, you can work through the system.

Give the plates a good clean with brake cleaner and then reassemble.

It may be worth bleeding through the clutch fluid and even changing it if it hasn't been done for a while; usually it will be done every 2 years as part of the major service.

Give it a really good bleed to ensure you get all the air (and old fluid if you're changing) out of the system and then reset the span adjusters and try again.

999 clutch problem
 

Thanks for the advice antonye, I will give this a go and hopefully this will work. I have heard dories of where the sometimes you get fluid leaking past the reservoir seals, but will do the fluid change and bleed first as I know that it hasn’t been changed for well over two years.3

999 clutch problem
 

Is there a particular sequence for bleeding the clutch antonye?

Just the same as the brakes -

with the bleeder nipple closed give the lever a good pump to ensure you have pressure
hold the lever under pressure and release the bleed nipple, catching expelled fluid
as the lever hits the bar/max travel, close the bleed nipple tight
now release the lever and pump again

You will want to do both at the slave cylinder AND at the master cylinder (at the lever) to ensure you remove any trapped air/fluid

Keep an eye on the reservoir to make sure it stays topped up.

Keep bleeding until you remove any bubbles and you get a nice clean flow of fluid through.

You may find it easier with the lever's span adjuster at the furthest point (largest span).

Discard used fluid responsibly at your local recycling centre!