No tire clearance; thanks for responses

Jim Hultman writes:

> Thanks for your ideas; it looks as if Vittoria, Avocet, IRC &
> Michelin may give clearance, & I'll attach an old touring tire
> sweeper as well. Time to experiment...

"Sweeper" aka tire savers? All those things do is fill your shoes
with dirt on days when the road is slightly damp and road debris
clings to the tire. I didn't know any bicycle shop still carries
those.

> Or.... Sheldon's 650B plan looks good; I'll need long rear brake
> calipers, but I'm not sure about the fork; a normal 700c fork or one
> designed for 650B wheels. Are 650B axles 100mm? I probably can't
> use a 650c time trial fork, as there's be no clearance for that big
> tire.

> Sheldon, if you're there...what brand of brake caliper did you use
> on your 650B bike. The bike looks terrific, by the way!

That's a pretty large difference. I doubt you'll find a brake with
that reach.

Jobst Brandt
[email protected]

Jim Hultman wrote:

> Sheldon's 650B plan looks good; I'll need long rear brake calipers, but I'm
> not sure about the fork; a normal 700c fork or one designed for 650B wheels.

You don't already have a fork? I'd go with one designed for 700c, as I
did on my IRO. Just need longer brake calipers.

> Are 650B axles 100mm?

There's no such thing as a "650B" axle, just tires and rims. All modern
front axles are 100 mm, but the hub doesn't care what size the rim/tire are.

> I probably can't use a 650c time trial fork,

If the bike was made for 700C and you put a shorter fork on it you'll
screw up the geometry.

> there's be no clearance for that big tire.
> Sheldon, if you're there...what brand of brake caliper did you use on your
> 650B bike.

Those are the Dia Compe BMX calipers that used to be on my daughter's
Cinelli BMX bike.

> The bike looks terrific, by the way!

Thanks! I had a very nice ride on it this afternoon, we finally got a
nice warm day, in the 40s (F) and sunny. Went out through Weston and
Sudbury, Glezen Lane and Water Row, for those who know the local roads.
Water Row is the nicest bit of cycling road I know of on this side of
the Atlantic. (Not quite up to the D41 from Port Royal to Chevreuse...)

Sure was glad I had the fenders though, 'cause the roads are all wet
from the melting blizzard. Tomorrow I'll need to put a mud flap on
the front fender, my feet got a bit wetter than I'd have liked.

I was pleasantly surprised how fast I was going on the IRO, found myself
using the top 3 gears (87, 100 & 115 inches) quite a bit more than I
would have expected.

Sheldon "http://sheldonbrown.org/iro" Brown
+-----------------------------------------------------------+
| I rise only to say I do not intend to say anything. |
| I thank you for your kind words and your hearty welcome. |
| --Ulysses S. Grant |
+-----------------------------------------------------------+
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

[email protected] writes:

> Jim Hultman writes:
>
>> Or.... Sheldon's 650B plan looks good; I'll need long rear brake
>> calipers, but I'm not sure about the fork; a normal 700c fork or
>> one designed for 650B wheels. Are 650B axles 100mm? I probably
>> can't use a 650c time trial fork, as there's be no clearance for
>> that big tire.

There are a number of critical measurements including the lateral as
well as radial clearance. There's an article in a Rivendell Reader a
couple of issues back with all the salient measurements.

>> Sheldon, if you're there...what brand of brake caliper did you use
>> on your 650B bike. The bike looks terrific, by the way!
>
> That's a pretty large difference. I doubt you'll find a brake with
> that reach.

Thdere's a whole subculture going on of converting tight-clearance
700C bikes to se 650B wheels, rather smaller than the singlespeed
subculture or the 29" subculture.

The increase in brake reach is about 19 mm, which can be covered on
many bikes with a Weinmann 750 centerpull brake. There are several
Web sites with pictures of several such conversions, although Google
didn't pull them when I tried just now. Might not be one of the 8
trillion Web pages they claim to have in their search engine.

Sheldon Brown wrote:

> All modern
> front axles are 100 mm, but the hub doesn't care what size the rim/tire
> are.
>
<pedant> unless it's a dynamo hub </pedant>

Zog The Undeniable <[email protected]> writes:

> Sheldon Brown wrote:
>
>> All modern front axles are 100 mm, but the hub doesn't care what
>> size the rim/tire are.
>>
> <pedant> unless it's a dynamo hub </pedant>

Eh? My SON is 100 mm OLN, Shimano generator hubs are 100 mm OLN.
What hubs did you have in mind?

Tim McNamara wrote:

> Zog The Undeniable <[email protected]> writes:
>
>
>>Sheldon Brown wrote:
>>
>>
>>>All modern front axles are 100 mm, but the hub doesn't care what
>>>size the rim/tire are.
>>>
>>
>><pedant> unless it's a dynamo hub </pedant>
>
>
> Eh? My SON is 100 mm OLN, Shimano generator hubs are 100 mm OLN.
> What hubs did you have in mind?

From Peter White's webpage [1]:

"The hub has a five year warrantee. I stock the hub in 24, 28, 32, 36,
40 and 48 hole versions. It can be safely used with both 26" and 700c
wheels (SON28), and is suitable for use on tandems. I also stock a
version for 16" and 20" rims (SON20) with 28, 32 or 36 holes. As of fall
2004, there are two new versions of the SON; the SONXS for Brompton
folding bikes, and SONXS for Dahon folding bikes. These folding bikes
use narrower front axles than on standard bicycles. The SONXS is
available in 28 hole drilling only. All SON hubs are rated at 6 volts
and 3 watts. Prices for hubs, lights and parts are toward the bottom of
this page."

So not only are there two different versions of the SON, the SON20 for
properly sized wheels, and the SON28 for large wheels, but versions with
73-mm and 74-mm OLN for Brompton and Dahon folders, respectively.

[1] <http://www.peterwhitecycles.com/schmidt-lumotec.asp>.

--
Tom Sherman - Earth

Tom Sherman <[email protected]> writes:

> Tim McNamara wrote:
>
>> Zog The Undeniable <[email protected]> writes:
>>
>>>Sheldon Brown wrote:
>>>
>>>>All modern front axles are 100 mm, but the hub doesn't care what
>>>>size the rim/tire are.
>>>
>>><pedant> unless it's a dynamo hub </pedant>
>>
>> Eh? My SON is 100 mm OLN, Shimano generator hubs are 100 mm OLN.
>> What hubs did you have in mind?
>
> From Peter White's webpage [1]:

<snip>

> So not only are there two different versions of the SON, the SON20
> for properly sized wheels, and the SON28 for large wheels, but
> versions with 73-mm and 74-mm OLN for Brompton and Dahon folders,
> respectively.

I was actually aware of those, as I am interested in folding bikes and
even own one, but being as these hubs are not intended for the bicycle
in question they are irrelevant, even to any but the most obsessive
pedant. And to pedant the pedant, his phrasing suggests that he
believes that all dynamo hubs use an OLN other than 100 mm, which
would be in error.

> Jim Hultman writes:
>>Thanks for your ideas; it looks as if Vittoria, Avocet, IRC &
>>Michelin may give clearance, & I'll attach an old touring tire
>>sweeper as well. Time to experiment...

[email protected] wrote:
> "Sweeper" aka tire savers? All those things do is fill your shoes
> with dirt on days when the road is slightly damp and road debris
> clings to the tire. I didn't know any bicycle shop still carries
> those.

(jh)>>Or.... Sheldon's 650B plan looks good; I'll need long
rear brake
>>calipers, but I'm not sure about the fork; a normal 700c fork or one
>>designed for 650B wheels. Are 650B axles 100mm? I probably can't
>>use a 650c time trial fork, as there's be no clearance for that big
>>tire.
>>Sheldon, if you're there...what brand of brake caliper did you use
>>on your 650B bike. The bike looks terrific, by the way!

(JB)> That's a pretty large difference. I doubt you'll find
a brake with
> that reach.

About 16~18mm so if your bike has 450 brakes now, skip the
next size, 500 and go to 730(in Shimano, 720). 810 are too
long.

"Tire wipers" or "sweepers" have their rabidly loyal
adherents (with some overlap to the tied/soldered clique).
Mere logic won't dissuade them.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971

>>>Sheldon Brown wrote:
>>>All modern front axles are 100 mm, but the hub doesn't care what
>>>size the rim/tire are.

>> Zog The Undeniable <[email protected]> writes:
>> <pedant> unless it's a dynamo hub </pedant>

Tim McNamara wrote:
> Eh? My SON is 100 mm OLN, Shimano generator hubs are 100 mm OLN.
> What hubs did you have in mind?

I paused fo that, too. I think he meant some dynamo hubs do
care what rim you use - the small wheel version is wound
differently.

--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971