Overall, this mod presented fewer problems than I had originally anticipated. So with the benefit of hindsight, the conversion is no problem at all provided you have access to a metal lathe and some one who knows how to operate it.
I did some thinking on how to avoid a complete custom job and to make sure that I can use as many OEM parts as possible whenever needed, especially with the bearings.
So here is what I did.
This is really easy: take out the Drifter wheel and put on the Meanstreak wheel! Same axle, same spacers, same disc rotor all a perfect fit!
Regarding the tire - there are a few comments on which tire size fits and should be used. The original Meanstreak tire, which is 170 wide, fits just nicely with a couple of millimetres to spare between the final drive housing and the swingarm on the right side.
This requires some thinking and exact working.
These things need doing:
#1) This is easy and straight forward enough. Best would be to hand over both discs and tell the shop to make the larger Meanstreak disc the same size as the smaller Drifter disc. This way you don't need to worry about measuring and if the shop stuffs up – well at least it is not your fault.
(Mind you don't be surprised if you realise the holes in the disc are not evenly spaced. The holes in my Meanstreak disc weren't evenly spaced at all and some of the punched holes remained complete and some are only left "halved". I guess this is what's called manufacturing tolerances)
#2) Axle adapters are easy but have one added issue (see D) which will have an impact on point 3!
Simply get a "spacer" done where the outside diameter fits the Meanstreak and the inside diameter fits the Drifter. The length can be such that when inserted into the wheel that they meet half way inside the hub. I did leave half an inch gap though which I fill up with grease. This little "reservoir" should (?) make the grease inside distribute itself evenly over time – well I hope anyway. Besides it doesn't cost anything anyway.
Have a look at the sketch for a better understanding
3) The spacers are a little dicy though. To get them done you should really have points 1 and 2 finished!
Put the front wheel back on with the brake disc mounted and position it such that it rotates freely as can be expected between the brake disc pads. Because of the manufacturing tolerances and every bike NOT being identical, the spacers MUST be measured for each bike anew, especially considering the thickness of the axle spacer "D" (refer sketch).
Take care that the float rings of the Meanstreak disc do not scrape on the inside of the Drifter brake calliper! There is only 1mm -1.5mm space or so! SO SPACE IS TIGHT! I had some spacers and played around with some very thin washers and figured it out in less then 10mins. I then took the washers and spacers and got some new ones made.
A little hint: Because space is so tight, just 0.5mm can make all the difference, so take the actual spacers you used for either side (don't mix 'em up) and get them micro measured! This is as close as you get to a guarantee to make things work.
I used the Meanstreak OEM tires (130/70 - 17). Even though these are mounted on 17 inch rims, the overall diameter may be up to an inch shorter than with Drifter tires on a 16 inch rim (130/90-16). This will vary by tire manufacturer.