700 wheels onto bike which takes 27"

hi there i have a question, i gave my friend my spare wheelset. later he gave them back to me
because they dont fit. it turns out his bike is a 20 years young bianchi with 105 set ups which
takes 27" wheels. he played around with the brake shoes too..

i wonder what needs to be done for it to work since 27 (686mm) and 700 are very close

best w

 

Depending on the frame, a pair of long-reach brakes should do it. Shimano recently put long-reach
Ultegra and 105-level brakes back on the market, but chances are these would be worth more than the
bike. (http://www.rivendellbicycles.com/webalog/brakes/) The RX100s actually look like a pretty good
value, but I haven't seen them in person.

Cheapest way to solve this problem is with some old Mafac or Diacompe centerpulls--total cost,
probably $25, including the cable hangers you'll have to add. You'll need to make sure your levers
work adequately with that setup, tho.

Cheers Colin Murphy

w e i wrote:

> hi there i have a question, i gave my friend my spare wheelset. later he gave them back to me
> because they dont fit. it turns out his bike is a 20 years young bianchi with 105 set ups which
> takes 27" wheels. he played around with the brake shoes too..
>
> i wonder what needs to be done for it to work since 27 (686mm) and 700 are very close
>
> best w

 

In article <[email protected]>, w e i <[email protected]> wrote:
>hi there i have a question, i gave my friend my spare wheelset. later he gave them back to me
>because they dont fit. it turns out his bike is a 20 years young bianchi with 105 set ups which
>takes 27" wheels. he played around with the brake shoes too..
>
>i wonder what needs to be done for it to work since 27 (686mm) and 700 are very close

If he has short reach brakes then a set of normal-reach calipers would probably make it work.
Shimano and Tektro models are both readily available. Hard to guess what's on the bike now since 105
could not have been original equipment in 1983.

--Paul

 

"w e i" <[email protected]> wrote in message
news:way2xtreme-C8117A.[email protected]...
> hi there i have a question, i gave my friend my spare wheelset.
later he gave
> them back to me because they dont fit. it turns out his
bike is a 20
> years young bianchi with 105 set ups which takes 27"
wheels. he played
> around with the brake shoes too..
>
> i wonder what needs to be done for it to work since 27
(686mm) and 700
> are very close
>
> best w

Try Alfred E. bike - http://aebike.com/ They have Tektro side-pull road calipers in 47-57mm for
$11.99 each, and 53-71mm, and 61-78mm for $9.99 each. Or you could look around for some Tektro dual
pivot long reach calipers - they were about $32 a pair last time I saw them advertised

The Shimano BR-A550 and BR-R600 dual pivots are nice, but a lot more expensive

 

>>... i gave my friend my spare wheelset. later he gave them back to me because they dont fit. it
>>turns out his bike is a 20 years young bianchi with 105 set ups which takes 27" wheels. he played
>>around with the brake shoes too..
>>
>>i wonder what needs to be done for it to work since 27 (686mm) and 700 are very close

You need to compare rim diameters, not the arbitrary traditonal size numbers. "27 inch" rims are
630 mm, while "700c" rims are 622 mm. That 8 mm diameter difference translates into a 4 mm
difference in radius.

Thus, to install 700c wheels in place of 27s, you need to _lower_ the brake shoes by 4 mm.

Someone trying to be helpful wrote:

> If he has short reach brakes then a set of normal-reach calipers would probably make it work.
> Shimano and Tektro models are both readily available. Hard to guess what's on the bike now since
> 105 could not have been original equipment in 1983.

What would today be called "short reach" brakes were very uncommon in the days of 27 inch wheels.

Talking about "normal-reach" is highly counterproductive, since "normality" changes with fashion.
The normal reach brakes seen on most bikes today have a reach range of 39-49 mm. The brakes you're
thinking of are more in the 47-57 range, and older bikes made for centerpulls often require
something longer than that, even for 27 inch wheels.

Sheldon "Numbers, Not Adjectives" Brown +-------------------------------------------------+
| One measurement is worth 50 expert opinions | --Howard Sutherland |
+-------------------------------------------------+ Harris Cyclery, West Newton, Massachusetts Phone
617-244-9772 FAX 617-244-1041 http://harriscyclery.com Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

 

hi guys thanks for the pointers, i even found something from sheldon's site later

this seemed to be a commonly asked question i just didn't know how to search

thanks w

> hi there i have a question, i gave my friend my spare wheelset. later he gave them back to me
> because they dont fit. it turns out his bike is a 20 years young bianchi with 105 set ups which
> takes 27" wheels. he played around with the brake shoes too..
>
> i wonder what needs to be done for it to work since 27 (686mm) and 700 are very close
>
> best w

 

Colin Murphy wrote: "Cheapest way to solve this problem is with some old Mafac or Diacompe
centerpulls--total cost, probably $25, including the cable hangers you'll have to add. You'll need
to make sure your levers work adequately with that setup, tho.

Cheers

Colin Murphy"

Egads, do they still MAKE these brakes? Where would you get them? Without breaking into some
bicycle museum?

Even Third Hand/Loose Screws doesn't have a set that I know of...!

May you have the wind at your back. And a really low gear for the hills! Chris

Chris'Z Corner "The Website for the Common Bicyclist": http://www.geocities.com/czcorner

 

On Mon, 14 Apr 2003 12:16:58 +0000, w e i wrote:

> hi there i have a question, i gave my friend my spare wheelset. later he gave them back to me
> because they dont fit. it turns out his bike is a 20 years young bianchi with 105 set ups which
> takes 27" wheels. he played around with the brake shoes too..
>
> i wonder what needs to be done for it to work since 27 (686mm) and 700 are very close

Brake reach is the only question. Older, "standard reach" brakes work best. Older Campy sidepulls
might work, with a bit of tweaking. Sheldon Brown sells "drop bolt" adapters for the rear -- usually
the front fits, but the rear has a bit too much for the newer brakes.

--

David L. Johnson

__o | Arguing with an engineer is like mud wrestling with a pig... You _`\(,_ | soon find out the
pig likes it! (_)/ (_) |

 

"Grenouil" <[email protected]> wrote in message

> Try Alfred E. bike - http://aebike.com/ They have Tektro side-pull road calipers in 47-57mm for
> $11.99 each, and 53-71mm, and 61-78mm for $9.99 each.

Anyone have any experience with these tektro super-long calipers? I'm planning on upgrading my
current cheaper-'n-sh** centerpull, and these are the ones that fit my budget best with the
necessary reach.

however, i cant help but wonder- they are decidedly un-graceful compared to 'normal' brakesets, made
for BMX perhaps? are they stiff? dependable? this would be the one brake on a fixie that sees a LOT
of traffic.

anthony

 

[email protected] (Chris Zacho "The Wheelman") wrote in message
news:<[email protected]>...
> Colin Murphy wrote: "Cheapest way to solve this problem is with some old Mafac or Diacompe
> centerpulls--total cost, probably $25, including the cable hangers you'll have to add. You'll need
> to make sure your levers work adequately with that setup, tho.
...
> Colin Murphy"
>
> Egads, do they still MAKE these brakes? Where would you get them? Without breaking into some
> bicycle museum?

Even cheaper is to keep an eye out on trash day. I frequently see 70's era low-mid range road
bikes in the trash with either Weimann 730 or Mafac centerpulls. Dissassemble, clean, lube, use
some Kool Stop salmon brake shoes and modern cables (see Sheldon Brown's nice article on cable
installation at http://www.sheldonbrown.com/cables.html ) and you'll have adequate brakes even
with the longer reach.

Bill "waste not, want not" Putnam

 

Chris Zacho The Wheelman wrote:

>
> Egads, do they still MAKE [Mafac/Diacompe centerpulls]? Where would you get them? Without breaking
> into some bicycle museum?
>
> Even Third Hand/Loose Screws doesn't have a set that I know of...!

Well, Chicago has two great resources for old stuff like this: a store called Urban Bikes with a
whole annex full of sorted and categorized parts dating back probably fifty years, and an ongoing
recycled bike sale called Working Bikes (http://workingbikes.org/sales.htm), both of which are great
sources for this kind of thing, and cheeep. So I'm probably spoiled with the ease of finding old
fitting parts.

Colin

 

[email protected] (ant) wrote in message
news:<[email protected]>...
> "Grenouil" <[email protected]> wrote in message
>
> > Try Alfred E. bike - http://aebike.com/ They have Tektro side-pull road calipers in 47-57mm for
> > $11.99 each, and 53-71mm, and 61-78mm for $9.99 each.
>
> Anyone have any experience with these tektro super-long calipers? I'm planning on upgrading my
> current cheaper-'n-sh** centerpull, and these are the ones that fit my budget best with the
> necessary reach.
>
> however, i cant help but wonder- they are decidedly un-graceful compared to 'normal' brakesets,
> made for BMX perhaps? are they stiff? dependable?

They are not stiff. They are, in my experience, dependably awful.

There are only two kinds of long reach (60mm+) sidepull brakes I've ever been able to get
sorta-halfway-decent braking out of (with good pads and a lot of fiddling around):

- Dia Compe Big Dog dual-pivot (out of production a long time)
- ACS Boa w/10mm center bolt (requires drilling out the fork crown)

Furthermore, these brakes usually need a high-ratio lever (like an old 4-finger MTB lever or a
motocross lever) to get them to work right. They might do OK with drop bar levers, but I've not
tried that yet.

BMX brakes are, after all, designed for coming to a stop after the sprint race is over. No big hurry
there. Racers aren't even _allowed_ to have one on the front.

If you need stopping power, long reach, and 6mm center-bolt mounting, the best solution is a U-brake
or V-brake adapter plate like one of these:

http://harriscyclery.net/site/page.cfm?PageID=49&Category=319

Both of these examples have arms that can be strapped to the stays or fork legs with hose clamps,
usually included. The resulting arrangement is heavy and ugly as a mud fence, but works quite well.

A tidier but slightly less powerful fix is to use the venerable Odyssey Pitbull bolt-mounted
rollercam brake. Its integral cable hanger can be removed in order to use a stem- or frame-mounted
housing stop (which is often more rigid):

http://shop.store.yahoo.com/penncyclebuy/odpitll.html

Chalo Colina