I did not pioneer this set up, Ippytattoo used to sell the Alto 2.5mm friction discs as a drop in 8 plate upgrade and Hugh and a few other did write ups on machining the basket. If you machined the basket with the 2.5mm discs you could probably do a 9 disc set up. But using where Ippytattoo had posted the Alto part number I found out they fit the xs650 ans gs1000. I know the XS stock plates where used is a bunch of yamaha bikes, but for this to work you need the 2.5mm discs. This means finding the "extra plate" clutch kit.
So I started my 8 disc conversion by ordering APE kit CKGS1000. This is their extra plate kit that has the 2.5mm discs. The kit has 9 discs, but unless you machine the basket you only need 8. The stack height ends up being .4mm more than stock, so you might need to adjust your clutch after. But you just stack it in like doing a stock replacement, with an extra steel and friction disc. No machining, no fuss, took about 1/2hr to do.
I haven't ridden enough yet to do a full report, but it doesn't shudder and grab like the stock plates did cold. Seems to grab nice and linear, and no slip I can notice and I tried to make it slip.
Here are pics of it installed. You can also see I drilled out the stock screws for the clutch to take allen bolts.
So I started my 8 disc conversion by ordering APE kit CKGS1000. This is their extra plate kit that has the 2.5mm discs. The kit has 9 discs, but unless you machine the basket you only need 8. The stack height ends up being .4mm more than stock, so you might need to adjust your clutch after. But you just stack it in like doing a stock replacement, with an extra steel and friction disc. No machining, no fuss, took about 1/2hr to do.
I haven't ridden enough yet to do a full report, but it doesn't shudder and grab like the stock plates did cold. Seems to grab nice and linear, and no slip I can notice and I tried to make it slip.
Here are pics of it installed. You can also see I drilled out the stock screws for the clutch to take allen bolts.