Rubber boot isn't the right term, it's called a diaphragm I think, takes up the free space below the master cylinder cap. Anyway this part will react badly with dot 4 and deform.

I changed to dot 4 as I already had a large dot 4 master cylinder. The large cylinder made the clutch action softer. I don't think that the dot 4 made any difference

The fluid is going to have zero effect in changing the mechanical advantage (the force required to pull the clutch). My GG uses the usual mineral oil... it's got the lightest clutch pull I've ever felt in my life, and I haven't felt it slip. I have no idea what Stu did to it, but it's pretty sweet...

Actually heffergm, ask about the original Jack. He had the first light spring made for the Pro clutch.

So, can anybody recall how look his clutch under top-hat? (My post #15).

Thanks.

In my opinion you dont need it. It was not on mine (new), now I got a s3 one which only has O rings.

Lian did you solve your problem?

I'd like to know if he solved the problem too as I have a similar problem.

I have a 2007 txt 280 and my brother has a 2010 txt 300. I only mention this as it is easy for me to compare one against the other and my problem is with the 280. 

 I have the same issue with clutch slipping as Liam describes, and have been through all the same procedures as him trying to resolve the cause, . Did Liam ever resolve his issue with a new pressure ring? It feels like the clutch does not engage quickly, when I pull the lever it feels like there is a tiny delay when released. The slip is only very slight, but having put brand new steels and fibres in (DP) it is exactly the same. Should I suspect the master cyclinder? Has anyone had this problem as resolved it?

I have a 2007 txt 250 that I bought almost new. This year the clutch seemed slow and when I rode a different bike it was really apparent. There is a fine line between having the clutch pack too thick (stiff pull) or too thin (soft pull, slow clutch). I bought one of these and my clutch is snappy again.

https://www.splatshop.co.uk/xiu-rdi-adjustable-spring-clutch-support-plate.html

Looks like what should be a standard fitment given the messing about that seems to be needed with these clutches.

Yes, its lucky for me that I can compare from the two gg's here. There is a lot of information here, with contradictions on the best oil, pressure plate going flat, I ordered another one but I don't think it is that. The previous owner put a new clutch in it as I made that a condition of its purchase, so he has been through all sorts trying to suss it out. I am all you-tubed up and beginning to suspect the master. I have a new set of plates and steels to go in and they are slightly thinner than the current set,  It is a lot of messing about I have the correct measurement for pack and it slips when dumping the clutch in any gear, then slowly bites to a stall, so baffling. Anyway, will persevere until I get it sorted out.

17 hours ago, sectionone said:

I have a 2007 txt 250 that I bought almost new. This year the clutch seemed slow and when I rode a different bike it was really apparent. There is a fine line between having the clutch pack too thick (stiff pull) or too thin (soft pull, slow clutch). I bought one of these and my clutch is snappy again.

https://www.splatshop.co.uk/xiu-rdi-adjustable-spring-clutch-support-plate.html

So I have just ordered one of these as well, thanks for your input .oh, and I thought I was being SOOOO individual with my user name, ha ha