smallest tire on a 700x27 rim?

chuck wrote:
>
> I know a 28c tire is too small. I'm wondering if a 32 or 35 will also be
> too small. I'm running 42c now, but things aren't as muddy as they were
> and I'd like to go a little smaller.

Is that 27mm inside the bead hooks, per ISO spec, or 27mm outside
width? I've had OK luck with tires that are just a couple of
millimeters wider overall than the rims they mount on. It seems to
diminish their cushioning qualities, though.

Chalo

On 2006-04-26, Chalo <[email protected]> wrote:
> chuck wrote:
>>
>> I know a 28c tire is too small. I'm wondering if a 32 or 35 will also be
>> too small. I'm running 42c now, but things aren't as muddy as they were
>> and I'd like to go a little smaller.
>
> Is that 27mm inside the bead hooks, per ISO spec, or 27mm outside
> width? I've had OK luck with tires that are just a couple of
> millimeters wider overall than the rims they mount on. It seems to
> diminish their cushioning qualities, though.
>
>

I'm not sure and I have no metric ruler. They're Sun Rhyno Lites if that
tells you anything. I guess it doesn't matter. I'm probably better off
using my narrower rims when I go smaller than 35c.

My bigger concern is getting a new rear deraileur since I busted mine
off on a ride today. Bent the hangar bad too. Can one get this aligned
close enough by eyeball or is an alignment tool of some sort needed?

Another question I have is about a SRAM X-7 deraileur. Will it be a
decent replacement for the 105 that broke?

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In article <fSS3g.25704$HC3.3723@trnddc07>,
chuck <[email protected]> wrote:
>On 2006-04-26, Chalo <[email protected]> wrote:
>> chuck wrote:
>>>
>>> I know a 28c tire is too small. I'm wondering if a 32 or 35 will also be
>>> too small. I'm running 42c now, but things aren't as muddy as they were
>>> and I'd like to go a little smaller.
>>
>> Is that 27mm inside the bead hooks, per ISO spec, or 27mm outside
>> width? I've had OK luck with tires that are just a couple of
>> millimeters wider overall than the rims they mount on. It seems to
>> diminish their cushioning qualities, though.
>>
>>
>
>I'm not sure and I have no metric ruler. They're Sun Rhyno Lites if that
>tells you anything. I guess it doesn't matter. I'm probably better off
>using my narrower rims when I go smaller than 35c.

_ I think you could run 30mm tires on those rims if you wanted,
but maybe not at as low a PSI as you might like. Peter White
says 35mm is the minimum.

http://www.peterwhitecycles.com/tourtand.asp

>
>My bigger concern is getting a new rear deraileur since I busted mine
>off on a ride today. Bent the hangar bad too. Can one get this aligned
>close enough by eyeball or is an alignment tool of some sort needed?
>
>Another question I have is about a SRAM X-7 deraileur. Will it be a
>decent replacement for the 105 that broke?

Newer SRAM's and Shimano use different cable pull lengths for
indexed shifting. You're probably better off sticking with
Shimano Deraillers if you have Shimano Shifters. You can use
an "MTB" rear derailler with road shifters if you want.

_ Booker C. Bense


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Booker C. Bense wrote:
>
> _ I think you could run 30mm tires on those rims if you wanted,
> but maybe not at as low a PSI as you might like. Peter White
> says 35mm is the minimum.

30mm _actual size_ might work, but that would more than likely be a
nominally "35mm" tire. Most 35s measure about 32mm on appropriate
rims, but they vary a lot. I have never seen a 700x30 or 700x32 tire
that measured anywhere near its nominal width.

Chalo

chuck wrote:
>
> They're Sun Rhyno Lites if that
> tells you anything. I guess it doesn't matter. I'm probably better off
> using my narrower rims when I go smaller than 35c.

Those measure 27.5mm outside width. You'll get the most satisfactory
results if you use tires of at least 32mm inflated width. That means
700x35 or wider.

You'd be better off trying to find a nice lightweight and supple tire
in the right size range than trying to use a tire that's too small for
the rim.

I highly recommend the Panaracer Pasela 700x35. It's the narrowest
tire I use, and the fastest as far as I can tell. It measures 32.5mm
on my 23.5mm wide rims. It has thin flexible sidewalls, a relatively
thin tread, and it doesn't cost much.

> My bigger concern is getting a new rear deraileur since I busted mine
> off on a ride today. Bent the hangar bad too. Can one get this aligned
> close enough by eyeball or is an alignment tool of some sort needed?

You should let a bike shop take care of that. You can probably get it
close enough to work, but a shop can align it better than new. They'll
also be able to diagnose whether more serious repair is necessary.

> Another question I have is about a SRAM X-7 deraileur. Will it be a
> decent replacement for the 105 that broke?

The X-7 won't work at all with your shifter. The SX-5 will work, and
costs a little bit less.

Modestly priced SRAM derailleurs these days are way too plasticky for
my liking. I have messed up a SRAM X-7 shifter when trying to replace
the cable, because some parts were made out of soft plastic that
shouldn't have been. The X-7 derailleur suffers from the same general
problem, but I haven't messed it up yet.

I really wanted to like SRAM derailleurs, since they are the decendants
of Sachs New Success derialleurs (my favorite ever), and since they are
made a company that appears less noxious in its business practices than
Brand S. I regret having to say it, but a Sh*mano derailleur is a
better product at the price point in question.

Chalo

On 2006-04-27, Chalo <[email protected]> wrote:
> chuck wrote:
>>
>> They're Sun Rhyno Lites if that
>> tells you anything. I guess it doesn't matter. I'm probably better off
>> using my narrower rims when I go smaller than 35c.
>
> Those measure 27.5mm outside width. You'll get the most satisfactory
> results if you use tires of at least 32mm inflated width. That means
> 700x35 or wider.
>
> You'd be better off trying to find a nice lightweight and supple tire
> in the right size range than trying to use a tire that's too small for
> the rim.
>

I ended up getting another cassette for my other rims. I figure a brake
adjustment and changing wheels is easier than tire/tubes. Plus, I had a
bunch of Conti TT 2000's 28c laying around to help make me go that
route.

> I highly recommend the Panaracer Pasela 700x35. It's the narrowest
> tire I use, and the fastest as far as I can tell. It measures 32.5mm
> on my 23.5mm wide rims. It has thin flexible sidewalls, a relatively
> thin tread, and it doesn't cost much.
>
>> My bigger concern is getting a new rear deraileur since I busted mine
>> off on a ride today. Bent the hangar bad too. Can one get this aligned
>> close enough by eyeball or is an alignment tool of some sort needed?
>
> You should let a bike shop take care of that. You can probably get it
> close enough to work, but a shop can align it better than new. They'll
> also be able to diagnose whether more serious repair is necessary.

It's a Giant cypress SX with 10K miles on it. All the miles are on a
limestone trail. I'd just like to get through this year. I'm now
interested in a touring bike that I can run 38c or maybe 42c tires on
while staying under $1000. I do want drop bars. I'm interested in any
advice on this.

>
>> Another question I have is about a SRAM X-7 deraileur. Will it be a
>> decent replacement for the 105 that broke?
>
> The X-7 won't work at all with your shifter. The SX-5 will work, and
> costs a little bit less.
>

I don't know if this makes a difference, but the shifters are SRAM.

> Modestly priced SRAM derailleurs these days are way too plasticky for
> my liking. I have messed up a SRAM X-7 shifter when trying to replace
> the cable, because some parts were made out of soft plastic that
> shouldn't have been. The X-7 derailleur suffers from the same general
> problem, but I haven't messed it up yet.
>
> I really wanted to like SRAM derailleurs, since they are the decendants
> of Sachs New Success derialleurs (my favorite ever), and since they are
> made a company that appears less noxious in its business practices than
> Brand S. I regret having to say it, but a Sh*mano derailleur is a
> better product at the price point in question.
>
> Chalo
>

chuck wrote:
>
> Chalo wrote:
> >
> > The X-7 won't work at all with your shifter. The SX-5 will work, and
> > costs a little bit less.
>
> I don't know if this makes a difference, but the shifters are SRAM.

If they worked with a 105 derailleur, they won't work with the X-7
derailleur. But they will work with the SX-5.

Chalo

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In article <eG04g.2857$E41.18@trnddc03>,
chuck <[email protected]> wrote:
>
>It's a Giant cypress SX with 10K miles on it. All the miles are on a
>limestone trail. I'd just like to get through this year. I'm now
>interested in a touring bike that I can run 38c or maybe 42c tires on
>while staying under $1000. I do want drop bars. I'm interested in any
>advice on this.
>

_ There are a lot more choices now than a few years ago, the REI
Randonne is a very nice bike in that price range.

_ Booker C. Bense

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On 2006-04-27, Chalo <[email protected]> wrote:
> chuck wrote:
>>
>> Chalo wrote:
>> >
>> > The X-7 won't work at all with your shifter. The SX-5 will work, and
>> > costs a little bit less.
>>
>> I don't know if this makes a difference, but the shifters are SRAM.
>
> If they worked with a 105 derailleur, they won't work with the X-7
> derailleur. But they will work with the SX-5.
>
> Chalo
>

Thanks for this advice. You saved me a week of waiting for a second
order. My old grip shifter was already worn through the rubber and many
coats of Shoe Goo anyways. Plus, Nashbar had the new one on sale for
$9.95. Its been many miles since this bike has shifted as well as it
does now. I guess $100 worth of parts should do that for a bike. After
replacing the sticky rear brake, the thing pedals a little easier
too...amazing.