Hi, here we go,
I have been wanting to try this for quite a while now, here's how I am going about it. So far so good.
Firstly, the dimensions I am looking for are disc to disc (outer) spacing of 130mm & 296mm disc diameter. These measurements are essential.
I have purchased a CBR 1100 blackbird front wheel from a 1998 model; casting number 61R. The original blackbird bearings fit the varadero spindle & Varadero spacers perfect.
The CBR Blackbird 61R wheel uses a 310mm diameter disc & they are of no use at all for this application as the varadero uses/needs 296mm diameter discs.
The disc rotor register/locator for a 61R wheel is 58mm & Disc mounting hole PCD is 74mm.
296mm discs that will fit the 61R wheel are.
CB 600 HORNET 2000-2006
VFR 750 F 1994-1997
CBR 600 F3 1995-1998
CBR 900 RR 94-97
VTR 1000 F FIRESTORM / SUPERHAWK 1997-2006
CB 250 HORNET 1996-now
RS 125 R 1991-2005
RS 250 R 1990-1997
TSR 250 1999-NOW
CBR400R NC23 1986-1987
CBR400RR NC23 1988-1989
CBR 400RR NC29 1990-1994
VFR 400 R (NC30) 1989-1992
CB 400N 1982-1988
But these all have a 17mm offset.
It is essential that I have an outer disc to outer disc measurment of130mm, for the discs to fit into the Varadero brake calliper spacing as normal.
The discs listed are the correct 296mm diameter and will locate on the 61R Blackbird wheel register & the mounting bolts line up. BUT, they have a 17mm offset. But this gives me 134mm = 2mm closer to the fork leg either side!
I needed to machine 2mm off either side of the standard 100mm wheel disc mounting faces. 96mm was the required hub width to get the correct 130mm disc spacing!
I mounted the wheel in the lathe, firstly holding it on the longer of the two side’s disc register collars. The collars are different lengths;I held it with the longer of the two collars firstly & machined 2mm off the shorter, opposite disc mounting face taking care not to touch the register/locator. Now the (newly machined) shorter of the two registers had an extra (new) 2mm of register/collar to grip in the lathe chuck, so when machining the other side it was safer to hold in the chuck to machine 2mm off the other side disc mounting face, again making sure not to touch the disc register collar.
Sorry, if it sounds complicated but it took me less time to machine than typing this out!!! If you get hold of a 61R wheel you will see what I mean about the different collar lengths etc.
Back home I deburred the machined faces, cleaned the disc mounting bolt threads then mounted the newly acquired Honda NC30 discs.
I measured up the discs and finally had the 130mm spacing as required. Spoton!
To fit the (new) wheel, both the callipers now need to be removed (like a normal sport bike) due to lack of space from the 17” wheel.
Bolted everything up & checked all was in order, all was good apart from the tyre missing…
Next, the wheel needs to be painted up to match the 5.5”rear in Halfords dark metallic grey.
Will update when tyres fitted, crossed fingers.