27 1/4 to 700C (Old Miyata)

[raff]

Hi everyone,
Im fixing an old Miyata road bike (1982 I think), I really want to change the wheels and put some 700C wheels, I know that some challenges might come, specially when it come to the brakes, has anyone done something like this on a Miyata? should I keep the old 27's (there not a lot in the market for this size) suggestions please!!
Thanks in advance!

[DaveM]

700 wheels will sit 4 mm lower than the 27's. If there's enough adjustment available on your brakes to move the pads down 4mm, there shouldn't be any problem. If not, you have to get new brakes which may or may not be an issue depending on what you have now, how long a "reach" you would need.

The other thing you need to figure out is the rear spacing on your frame (between the rear dropouts). Probably 127 mm, but you should check before buying anything. Next is if you have a freewheel or cassette. You would need to get the new wheel to match or think about changing over your drive train.

The selection of 27" wheels and tires is definitely less than for 700, but there's quite a bit of stuff out there. Are you looking to get something specific, or just a good quality replacement wheel. Why are you changing the wheels?

[raff]

I want to get a better quality wheels and also i want to get a 9 speed cassette, also I want to go with black rims, the bike is an oldie and has silver rims, i want to make it look more Slick and a better bike! I really like the frame!! Thanks a lot for taking the time to reply to my question.
Im going to pay a visit to my mechanic and see what can he offer me.
any suggestions are more than welcome!!

(06-08-2012, 01:43 PM)DaveM Wrote:  700 wheels will sit 4 mm lower than the 27's. If there's enough adjustment available on your brakes to move the pads down 4mm, there shouldn't be any problem. If not, you have to get new brakes which may or may not be an issue depending on what you have now, how long a "reach" you would need.

The other thing you need to figure out is the rear spacing on your frame (between the rear dropouts). Probably 127 mm, but you should check before buying anything. Next is if you have a freewheel or cassette. You would need to get the new wheel to match or think about changing over your drive train.

The selection of 27" wheels and tires is definitely less than for 700, but there's quite a bit of stuff out there. Are you looking to get something specific, or just a good quality replacement wheel. Why are you changing the wheels?

[Joe_W]

Well, the quality of the wheel depends first and foremost on the build. You can build a decent wheel even from lower end components (well, non-racing stuff, which should also last longer). So if 27" wheels are not available in the specs you are looking for, a competent mechanic can build such a wheel. They are usually not [i]that[7i] expensive considering the parts they use (higher end) and the amount of work it is. Check
http://www.slowtwitch.com/Tech/Bearing_Breakdown_2822.html
for a discussion of bearings and what makes sense for most of us...

Before you upgrade to 9speed, check the rear frame spacing, the distance between the dropouts / the over locknut distance (OLD) of your old wheel. If this is less than 130mm: bummer, your frame is too narrow. If (and only if) you have a steel frame you could adjust it (carefully bend it open a couple of mm on each side). I probably wouldn't try that on very high end frames...

[nfmisso]

If your Miyata has the original brakes, definitely change to modern dual pivots - like Tektro. Measure 'brake reach', and read about brake mounting: http://www.sheldonbrown.com/calipers.html

See also my project 310: http://forums.bikeride.com/thread-3598.html

The Tektro 536 brakes I went with allow either 700c (ISO 622) or 27 (ISO 630) rims.

The frame is flexible enough to bend a couple of millimeters on each side, but will be tight for a 130mm OLD hub (required for 9 speed).

[Joe_W]

... basically not only 9 speed but also any new(ish) road hub, no matter what's the number of gears. Mountain bike hubs are 135 mm wide, no way you can fit one of those, so watch out!

[1FJEF]

Depends how much you weigh too. You can look here for 27" wheelsets. They offer final tension & true here. An employee told me 200lbs absolute max rider weight with about a 30lb bike. A purchaser told me the Quando sealed bearings lasted only 2 months. Here's another place. All of these wheelsets will fit your frame.