Can you put 700c wheels on a 27" old bike ??

[Joe Potter]

Hello all,

I am looking to fix up an old road bike. As I got it, the bike has a 27"
wheelset on the back of the bike and a 700c on the front with brakes that
"sorta match" the 700c front rim. (27" is what came with it)

Is it even possible to convert to 700c wheels? If so, what all needs to be
replaced or adjusted?

If not, what is the best bet to replace the 700c front wheelset?



Also, can you change a 5 speed cassette to a 6 or 7 on this bike?
(it has 3 in the front)



Thanks.

--
Regards, Joe

[RG]

"Joe Potter" > wrote in message
. com...
> Hello all,
>
> I am looking to fix up an old road bike. As I got it, the bike has a 27"
> wheelset on the back of the bike and a 700c on the front with brakes that
> "sorta match" the 700c front rim. (27" is what came with it)
>
> Is it even possible to convert to 700c wheels? If so, what all needs to
be
> replaced or adjusted?

Yes, assuming that there is sufficient width between the rear fork blades
for the width of 700 rim and tyre you want to use - a couple of issues
though :

1 Brakes may need replacing to get the reach for the blocks to line up with
the rims

2 The rear stays may need opening out a little to handle the slightly wider
axle normally found on "modern" 700 wheels - assuming the frame is steel
(probably is if the bike started out with 27 wheels) then Sheldon Brown has
an intriguing method to open the stays, see his site. [The method seems
pretty frightening but if you take it slowly and gently it does work ....
I've done a couple of frames without any problem)

>
> If not, what is the best bet to replace the 700c front wheelset?
>
>
>
> Also, can you change a 5 speed cassette to a 6 or 7 on this bike?
> (it has 3 in the front)

Shouldn't be a problem - again I changed a 1970s 27 inch wheel bike with 2
on the front nnd 5 on the back to 700 rims with 7 on the back using all the
original componentry (I'm just about to chnage the front to a triple and
that will need a longer BB axle but the changer should still work OK)


Best of luck

Rob


>
>
>
> Thanks.
>
> --
> Regards, Joe
>
>

[David L. Johnson]

On Mon, 28 Jul 2003 13:45:53 +0000, Joe Potter wrote:

> Hello all,
>
> I am looking to fix up an old road bike. As I got it, the bike has a 27"
> wheelset on the back of the bike and a 700c on the front with brakes that
> "sorta match" the 700c front rim. (27" is what came with it)

Well, a lot of bikes back then could handle either size (tubulars are the
same size as 700c, and 27" were the only clinchers widely available in the
US, which explains why). You will have to lower your brake blocks 4mm.
If there is that much room, you are good. If not, you may need to get new
long-reach brakes, or a "drop bolt", a special attaching bolt with a
displacement.

For the rear wheel you may have to spread the dropouts to fit in a
standard 130mm cassette hub. A good bike shop can do this for you cheaply
if you don't trust yourself to use Sheldon's method.

You can use your old hub, and just replace the rim, if you can handle
building a wheel.

> Also, can you change a 5 speed cassette to a 6 or 7 on this bike? (it has
> 3 in the front)
>
This would force you into the spreading of the rear. It is no big deal,
since you only need eitehr 4 or 10mm extra, depending on what you have.
Then you can go 9 in the rear, or even 10 if you want Campy, but that is
pretty pricey for an old bike.

--

David L. Johnson

__o | If all economists were laid end to end, they would not reach a
_`\(,_ | conclusion. -- George Bernard Shaw
(_)/ (_) |

[Joe Potter]

David L. Johnson wrote:

> On Mon, 28 Jul 2003 13:45:53 +0000, Joe Potter wrote:
>
>> Hello all,
>>
>> I am looking to fix up an old road bike. As I got it, the bike has a 27"
>> wheelset on the back of the bike and a 700c on the front with brakes that
>> "sorta match" the 700c front rim. (27" is what came with it)
>
> Well, a lot of bikes back then could handle either size (tubulars are the
> same size as 700c, and 27" were the only clinchers widely available in the
> US, which explains why). You will have to lower your brake blocks 4mm.
> If there is that much room, you are good. If not, you may need to get new
> long-reach brakes, or a "drop bolt", a special attaching bolt with a
> displacement.
>

I think the brakes are "long-reach", perhaps a simple adjustment will do the
trick. If I can get them freed up with WD-40 I'll give it a try.



> For the rear wheel you may have to spread the dropouts to fit in a
> standard 130mm cassette hub. A good bike shop can do this for you cheaply
> if you don't trust yourself to use Sheldon's method.
>
> You can use your old hub, and just replace the rim, if you can handle
> building a wheel.
>
>> Also, can you change a 5 speed cassette to a 6 or 7 on this bike? (it has
>> 3 in the front)
>>
> This would force you into the spreading of the rear. It is no big deal,
> since you only need eitehr 4 or 10mm extra, depending on what you have.
> Then you can go 9 in the rear, or even 10 if you want Campy, but that is
> pretty pricey for an old bike.
>

I do not really need more gears. Here in Orlando we do darn few hard climbs!

Thanks much for your information.



--
Regards, Joe

[Pete Biggs]

Joe Potter wrote:

>> 1 Brakes may need replacing to get the reach for the blocks to line
>> up with the rims

> A fellow at the LBS seemed to think that old 80's road bikes would not
> accept new brakes becuase of where the mounting holes are. Anything to
> that?

Not really. There are modern brakes available to fit. Fenders or extra
long reach can complicate matters but these problems can be overcome.
Also, allen key type brakes can be used by enlargening the holes to accept
the recessed nuts - this will increase your choice of calipers although
may not be necessary as some old-style "nutted" brakes are still
available. The drilling is an easy job though.

Note. The brake pads will only need lowering by 4mm. This may already be
possible as is, or if caliper slots are filed.

I've done all this (700c wheel with old brakes, and new brakes, and
respread frame to 130mm) myself with a 1985 bike that took 27" wheels.

~PB

[David L. Johnson]

On Mon, 28 Jul 2003 23:20:32 +0000, Joe Potter wrote:

> A fellow at the LBS seemed to think that old 80's road bikes would not
> accept new brakes becuase of where the mounting holes are. Anything to
> that?

Well, sort of. Modern brakes -- most of them, are very short-reach, and
older frames expect a longer reach in order to accomodate old-fashioned
ideas like fenders, fat tires, and even 27" wheels. No longer do we worry
about any of that. But it has brakes already, right?

--

David L. Johnson

__o | Let's not escape into mathematics. Let's stay with reality. --
_`\(,_ | Michael Crichton
(_)/ (_) |

[David L. Johnson]

On Tue, 29 Jul 2003 01:11:33 +0100, Pete Biggs wrote:

>> A fellow at the LBS seemed to think that old 80's road bikes would not
>> accept new brakes becuase of where the mounting holes are. Anything to
>> that?
>
> Not really. There are modern brakes available to fit.

True

> Also, allen key type brakes can be used by enlargening the holes to accept
> the recessed nuts - this will increase your choice of calipers although
> may not be necessary as some old-style "nutted" brakes are still
> available. The drilling is an easy job though.

Well, most 1980s bikes did use allen-key brake bolts, at least the
high-end ones did. It was the 1960s and early 70s when you often had to
drill out the brake bolt hole. I did this on a couple of bikes. The
front is no problem. The rear is.

--

David L. Johnson

__o | It doesn't get any easier, you just go faster. --Greg LeMond
_`\(,_ |
(_)/ (_) |

[Joe Potter]

David L. Johnson wrote:

> On Mon, 28 Jul 2003 23:20:32 +0000, Joe Potter wrote:
>
>> A fellow at the LBS seemed to think that old 80's road bikes would not
>> accept new brakes becuase of where the mounting holes are. Anything to
>> that?
>
> Well, sort of. Modern brakes -- most of them, are very short-reach, and
> older frames expect a longer reach in order to accomodate old-fashioned
> ideas like fenders, fat tires, and even 27" wheels. No longer do we worry
> about any of that. But it has brakes already, right?
>

Yes, it has brakes. The ones on the front do work and I have ridden the
bike. The brakes have a real long arm compared to my 1999 cannondale. But
they do touch the tire a bit and do not look "straight" to me.

I am afraid the brakes will need to be soaked in WD-40 before any more
adjustments are made.




--
Regards, Joe