I am hoping to convert the wheels on a Bridgestone MB-2 to quick release. I have done a bit of research and am thinking the best bet is to buy replacement axels with the cones, spacers etc. A couple of things I am wondering about, and would appreciate feedback on. For this I am presuming I will need to have a smaller axel than what I presently have, as I have been told quick release axel diameter is smaller than my solid axel.

1. How critical is the cone radius, or is it critical at all?
2. Will my freewheel, cassette (shimano 600) move over to a different size axel?
3. Anything else I should be concerned with?

Check to see if you have a 10mm rear axle and a 9mm front axle, which are the standard QR axle diameters. If you don't, the wheels really won't sit that well in the dropouts anyways. They did make 10mm and 9mm nutted axles and I don't think your bike varies from that.

I did this on a '91 Fuji Sandblaster with Shimano GS100 hubs last month that had a stripped axle. Bought a kit that included axle, cones, lock nuts and spacers (https://www.amazon.com/gp/product/B00...?ie=UTF8&psc=1). Hassle free swap and works great.

I've done it in the past. New axel, cones, spacers, locknuts, and a skewer. then time to set it up it what it takes. The bearing my contact the cups in the hubs in a different spot, but if the wheel spins freely, that's no big deal.

1- Cone curvature is important in that both the spot on the cones that the balls contact needs to be between the edges (within the curved surface) as well as the curve is not too tight for the hub's ball diameters. So the balls need to fit on the curve close to it's center and not touch at two points (if the balls were to large for the curve). Front hubs that use 3/8" (9.5mm) axles can have either 3/16" or 1/4" ball diameters, their coves are shaped for the stock ball diameter and ball count.

2- Every FW or cassette I've seen has a center hole with enough clearance for 3/8" or 10mm axles. It's the hub shell/free hub body that really controls the cogs mounting. Now the axle does need the correct amount of extension/spacers so the cogs don't hit the inside of the drop out/seat stay or sit so far away the the rear der can't swing far enough in to the large cog.

3- Yes, Cone OD needs to fit through the hub shell's dust cap. If the cone has a press on dust cap then this needs to fit within the shell's spot for it. The cone's length needs to be enough to have the wrench flats be outside the dust cap, or doing bearing adjustments and cone/lock nut tightening gets REAL frustrating. The easiest way to assure all these issues is to get an axle with the same diameter and thread pitch. Then all the cones, spacers and lock nuts can just transfer over. BTW many classic front nutted/solid axles are a smaller diameter then the QR version. Many rear axles have the same diameter for both. Any changes to the cones or lock nuts will likely mean that the spacers will need playing with. So getting extra 1mm spacers can save a return to the shop. bring in all your parts when you go so their trained eyes can help reduce the challenges by providing the best fits the first time. Andy.

Thanks for all the great advice here, I really appreciate it. Got home from work today and somehow my son lost the rear derailleur riding home from school. That may be material for another thread . . . .

Unless you need to often remove the wheels, such as for transport there is no advantage to q/r wheels. In addition to other factors noted the cone needs to be long enough so that the cone adjustment flats extend beyond the dust caps but no so long that it affects the wheel dishing.

I have found the cost of good, used wheels is as cheap or cheaper than a replacement axle and skewer. And in your case, you are talking old school mtb. Those go really cheap. Heck, I just donated several to my local co-op. I have found nice used six and seven speed mtb wheels cheap, really cheap.