27" to 700c only requires 4 mm more brake reach, so your current centerpulls may have enough adjustment. They should work OK with new pads and cables.
That also equates to 4 mm more tire clearance. I did a 27" to 700c conversion as part of an overhaul of my girlfriend's father's 80s Raleigh USA Marathon. It fits a 700 x 32 tire under an SKS P45 fender, although the clearance is pretty tight under the rear brake bridge. Tektro R539 medium-reach calipers had the proper reach. As for the rear hub, you should be able to cram a 126 mm hub in there without cold-setting the stays. But it will be a challenge each time you install or remove the rear wheel. Some folks have luck re-spacing hubs by adjusting and/or removing spacers on the axle, and then re-dishing the rim. You may be able to remove a 5 mm spacer on the non-drive side of the axle. On Wed, Mar 1, 2017 at 12:30 PM, Wayne Naha <w.r.n...@gmail.com> wrote: > I would like to keep this conversion as simple as possible, so changing > out the BB is not a priority. A five speed freewheel plus a triple > chainring crank is plenty enough for me. The existing brakes are CP, > though I was thinking of replacing them with the longer reach Silver side > pulls. I don't think the current CP brakes have sufficient reach. The > brake levers are original, and leave much to be desired. And while the > current headset is not showing any signs of a problem, I do have an Ultegra > headset not doing anything in my parts bin. I may as well throw it on. > > > On Wednesday, March 1, 2017 at 1:09:24 PM UTC-5, George Schick wrote: >> >> If the hub/FW is a five speed that would mean 120mm spacing. There >> should be no need to cold set anything if you can find a 120mm hub. Check >> eBay for NOS. If you want to bump it up to a 6 or 7 speed then you'll need >> to widen the rear spacing a bit (to 126mm) by cold spacing (see Sheldon for >> details on that) for smooth installation and removal of the wheel. >> 'Course, that'll also mean a new FW *and* you may have to change the BB >> cartridge again to get it properly aligned with the wider rear. I don't >> think I'd bother doing that if the existing FW is still in good shape and >> just keep it a five-speed. BTW, what kind of shape is the headset in? You >> didn't mention that being replaced in your OP. If the brakes are CP and >> you want to change to SP, you'll be removing the brake cable hanger so it >> might be a good time to consider a new headset - especially if the existing >> is "indexed." >> >> On Wednesday, March 1, 2017 at 11:54:58 AM UTC-6, Wayne Naha wrote: >>> >>> I had wanted all sparkly new hubs, along with the new rims. But the >>> rear spacing issue had slipped my mind. The freewheel is in decent shape, >>> and it is a five speed, so that means 120mm spacing? What about 'cold >>> setting' the rear triangle? Any downside to that? >> >> -- > You received this message because you are subscribed to the Google Groups > "RBW Owners Bunch" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to rbw-owners-bunch+unsubscr...@googlegroups.com. > To post to this group, send email to rbw-owners-bunch@googlegroups.com. > Visit this group at https://groups.google.com/group/rbw-owners-bunch. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To unsubscribe from this group and stop receiving emails from it, send an email to rbw-owners-bunch+unsubscr...@googlegroups.com. To post to this group, send email to rbw-owners-bunch@googlegroups.com. Visit this group at https://groups.google.com/group/rbw-owners-bunch. For more options, visit https://groups.google.com/d/optout.
