Citykid

Need to replace the rear wheel on my '91 Schwinn Voyageur. I replaced the bearings and regreased hub but realized the cones are scarred and can feel significant drag on the rear wheel.

Looking to take the opportunity to set up a dynamo hub system on the front wheel sp my question is: are there any reasonably-priced pre-built 27" dynamo hub wheelsets out there??

I am concerned with the idea of moving to 700c wheels because of the canti-brake post placement but also because of compatibility with my current 7-speed set up. I believe the rear wheel is spaced at 126mm.

Secondary question: are these concerns unfounded? I have no real reason to move from 27" besides the increased tire selection...

bikemig 

It can be tough to move from 27 inch to 700c on a bike with cantilever posts. The fact that the bike has 126 mm really doesn't matter. The canti posts on vintage bikes tend to be narrower than modern bikes which can make finding a modern canti difficult and not all have the needed adjustability for a 700c wheel.

As you said, the real difference to think about a 700c wheel is greater tire/rim availability.

Have you thought about going with a quality sidewall dynamo? Dymotec

jpaschall

Will probably just have to build it up custom with your LBS.

mstateglfr 

any chance you have a bike with a 700c wheel? or a neighbor with one? Just toss the front wheel on your Voyageur and mess with the cant brake to see if it will line up.
'91 may be new enough where the posts arent as close as they were in the 80s. Total guess there, admittedly.

If you are getting a new front wheel, and adding a dynamo hub- no reason to skimp and not just get a new wheelset entirely.

...or build a wheel.

Narhay

I think there are some cantilever brakes that allow more downward adjustment than others for a 27 to 700 conversion. Someone will chime in with which they are.

Otherwise you can learn to build a wheel. No time like the present to learn.

The Golden Boy 

The easy ones are Shimano BR-MC70, M732, MT-60 and the Suntour XC Pro. I don't know if the Suntour XCE brakes have the same adjustability.


I'm still sorta OK with 27" wheels/tires- but now I opened that box- I've got secret plans to get 10 speed 700c wheels for all my bikes!!!

52telecaster

i build dyno wheels all the time. look on ebay for 36 hole dynohubs and you'll find a buy it now for 40.00 or so. then do your spoke calculator and call, yes call dan's comp(888-888-3267) for your spokes. for double butted they will be .40/each with about 5.00 shipping. this is of course predicated on having a rim. you could even use your current front rim if its in decent shape. as for quality of hubs, just let me say i havnt run into a bad one of any brand yet and i have built at least 10 dyno wheels. all of mine were cheaper shimanos, panasonics or sanyos. i've put many miles on all of the brands.

machinist42

Months ago I swapped in 622 wheels for the 630s on my Lotus Odyssey, simply to see if there would be compatibility issues with the brazed on cantis.

Without any adjustment they worked perfectly. Yup. I thought to myself, "What manner of sorcery is this?" and "Have I gone insane?" and "How can this be?" and "This Lotus Odyssey is truly a magical bicycle!"

Took me a few hours, but I sussed it out with images in my head like a benzene snake eating its own tail. The 622s sported a much narrower rim width.

Now the Redline Tee-Ex was stolen in December, so I no longer have those wheels and can't measure them. The 630s are here but have no markings save for 630x15DIN and 27x1 1/4 ERTA. (I guess I could get out the calipers, but I am really busy today, and lazy always.)

I'm sure there is a loss of braking efficiency in this equation, but one may be able to compensate for that with a shorter yoke?

Anyway, I don't think I've seen rim width brought up as a variable in this conversion, so...

ThermionicScott 

That's an excellent point, and thank you for the Cormac McCarthy article.

My fixed-gear MTB has a canti brake in front, and a few years ago I bought a spare 26" front wheel so that I wouldn't need to mount/dismount the studded tires on both wheels each year. The winter wheel has a narrower rim, so the brake pads hit a little lower.

Citykid

Threw a very narrow 700c Mavic rim in this afternoon, and while close, the brakes were a little too high. Glad I tried before impulsively buying a wheelset and hoping for the best.

Citykid

The original brakes on the bike were Suntour XCE but I recently swapped them out for Tektros. Unfortunately the Tektros are just a little short on the downward adjustment for a conversion.

Citykid

Thanks for your input. You've inspired me to bid on a new Shutter Precision going far below its retail price. Unfortunately without a truing stand I think I may be better served taking this one to the LBS.

The Golden Boy 

Lords of Light!

Ariel! Ookla! Ride!!!

Lascauxcaveman 

You could save them some time (your money) and try to lace the new wheels up and get them "close" by doing a rough truing with new wheel mounted on your bike. That was my plan on my first wheel build and ended up getting the thing pretty much perfect, so it never made to the LBS. The process seems pretty complicated at first, and I did have to go back and undo things once, but it was relatively easy to see it through to the end.

jimmuller 

What @Lascauxcaveman said. You can true and dish a wheel on your bike. Yeah, it's inconvenient to keep flipping it over to check the dish, but it can be done. Building and truing takes patience anyway, might as well enjoy the process.

I built a front wheel with a Shutter Precision SV-8 and I can tell you, it works really well. Start riding, the lights come on, end of story.

One caution about building a wheel, triple check your spoke lengths. Check your rim's ERD, and be aware that ERD is misnamed - it should be Effect Spoke Head Diameter. You can measure ERD several different ways, do all of them at several different point around the rim. The reason for being compulsive about it is that not all the data in the various databases are correct. Even measure your hub dimensions if you feel so inclined, even though the hub has a smaller effect on spoke length.

Of course, by the time you buy the hub and spokes and maybe the rim it won't be so cheap anymore, but knowing you just rode 1000 miles on your own wheel is pretty satisfying.

Citykid

That's a great idea. Did you buy your rim, spokes and nipples online? I would use my old rim but its the commuter so I can't have it out of commision for more than a couple of days. Someone above posted about Dan's Comp as a source spokes and nipples. Should I just use one of these online spoke length calculators?

Lascauxcaveman 

That sounds like a good way to go. Everyone seems to recommend Danscomp, and the online calculators work fine.

I used one to verify that the collection misc spokes I had (from several dead wheels) would work with the hub I had (from the Box o' Crap game) and the rim I had (a badly tacoed Weinmann RM19 that I re-flattened using the flat table top method). I had the advantage of all this old junk sitting around, so I didn't actually have to buy anything to try my first wheel build. Front wheel, so no dishing, everything symmetrical and simple.

First ride on the newly built wheel was intentionally abusive; 5 miles of fast back-alley running with very rough pavement, unpaved sections, hopping down from curbs, etc. It came a little out of true, but still well within the usable range. No hop. I haven't tried re-tensioning yet.

seedsbelize 

It's a front wheel. Use your fork for a truing stand.