I'm going to fit a 2005 case to my 2002 Pro.

Do I need to change the seal in the master cylinder or just clean the brake fluid out and flush the hose out before filling with mineral oil?

The case comes complete with slave piston, seals etc.so that will be OK.

Thanks

A new seal kit for mineral oil is needed or the new master cylinder as it is smaller.

 Just thinking, you cannot just replace the case. The 2002 was different shape. The gasket was different.

You can replace the 2002 case with the 2005. Pretty sure the master cylinder from the 2002 bike was a standard 9.5mm bore, so a later model mineral oil kit would be all that is needed and as Lineaway says, the clutch hose would need cleaning out. You can't use the original master piston kit as the seals would swell with mineral oil. You should be able to get a metal type cover gasket from BVM if you need one. The only gasket difference between the 2002 and later Pro's was the crankcase gasket, which is specific for the 02 model only. The gearbox casing was "deepened" to allow for more oil in the gearbox and had 1 screw fixing hole set differently. Bye, Peter B.

The center cases were different, but I thought the clutch case was different too. I never got a 2002 parts listing.

Thanks for the replies,

Think I've got there.

There was a tech sheet somewhere that listed a part no for the upgrade. It was the later casing, slave seals, piston and spring and mentions the master cylinder seal kit. I now realize that there is different seal material for mineral and Dot 4. 

I note that the o rings on the slave cylinder are the same for both mineral and Dot4.

I've had an 03 pro that uses Dot4 and that has never been a problem. The 02, even with new o rings has always needed bleeding if left more than a week due to fluid leaking past the slave seals.

Hi Lineaway, correct with the crank cases, and to a point with the clutch case for the 2002, this casing did not have any webbing to support the slave piston action and would flex slightly when using the clutch, creating a dragging clutch. The later year casings had an interior web to strengthen the slave piston and prevent casing flex.

Hi eddie1, the slave O rings are teflon coated something, which I can't remember and may well be ok for either synthetic or mineral oil, but......you mentioned fitting a 2005 case, this has an O ring plus a cup seal in the slave cylinder, if green then the cup seal is for mineral, if black then this is suited for DOT4. Bye, Peter B.