gearing mods

[visionset]

I've got a Tiagra groupee 52/39 12-23. Although I'm getting much
fitter, I'm not sure the lowest is low enough, for the 1 in 4 & 5
Derbyshire hills I seem to be frequenting. I have to get out of the
saddle, and can't really do that for the length of some of the hills.
Ideally I reckon going to a more compact set up would be best, but I'm
guessing that's a new crank for the less than 39 tooth ring. I still
want to maintain the 'out and out' road racer. I guess the other
option is to maintain the same 8 speeds of the 9 speed cassette and
swap the 23 out for a 25. But then I'm guessing we're in realms of
esoteric cassettes or DIY pin removal? Any decent discussions on
this? Links?

Cheers,
Mike W

 

[rothers]

On Sun, 1 Jun 2008 02:51:54 -0700 (PDT), visionset <[email protected]> wrote:

>I've got a Tiagra groupee 52/39 12-23. Although I'm getting much
>fitter, I'm not sure the lowest is low enough, for the 1 in 4 & 5
>Derbyshire hills I seem to be frequenting. I have to get out of the
>saddle, and can't really do that for the length of some of the hills.
>Ideally I reckon going to a more compact set up would be best, but I'm
>guessing that's a new crank for the less than 39 tooth ring. I still
>want to maintain the 'out and out' road racer. I guess the other
>option is to maintain the same 8 speeds of the 9 speed cassette and
>swap the 23 out for a 25. But then I'm guessing we're in realms of
>esoteric cassettes or DIY pin removal? Any decent discussions on
>this? Links?

On my hybrid I run 105/Ultegra 50/36 12-27 which is about the most I can squeeze
out of the lower end without going to a triple and long throw rear.

Neil

 

[visionset]

On 1 Jun, 11:30, rothers <[email protected]> wrote:
> On Sun, 1 Jun 2008 02:51:54 -0700 (PDT), visionset <[email protected]> wrote:
> >I've got a Tiagra groupee 52/39 12-23. Although I'm getting much
> >fitter, I'm not sure the lowest is low enough, for the 1 in 4 & 5
> >Derbyshire hills I seem to be frequenting. I have to get out of the
> >saddle, and can't really do that for the length of some of the hills.
> >Ideally I reckon going to a more compact set up would be best, but I'm
> >guessing that's a new crank for the less than 39 tooth ring. I still
> >want to maintain the 'out and out' road racer. I guess the other
> >option is to maintain the same 8 speeds of the 9 speed cassette and
> >swap the 23 out for a 25. But then I'm guessing we're in realms of
> >esoteric cassettes or DIY pin removal? Any decent discussions on
> >this? Links?
>
> On my hybrid I run 105/Ultegra 50/36 12-27 which is about the most I can squeeze
> out of the lower end without going to a triple and long throw rear.
>
> Neil

You can get down to 36 on a standard 130mm PCD crank?, what chainrings
are these?

 

[Pete Biggs]

visionset wrote:
> I've got a Tiagra groupee 52/39 12-23. Although I'm getting much
> fitter, I'm not sure the lowest is low enough, for the 1 in 4 & 5
> Derbyshire hills I seem to be frequenting. I have to get out of the
> saddle, and can't really do that for the length of some of the hills.
> Ideally I reckon going to a more compact set up would be best, but I'm
> guessing that's a new crank for the less than 39 tooth ring.

38t is the minimum for 130mm.

I think you would be happier with a compact chainset AND a cassette with a
bigger big end.

~PB

 

[rothers]

On Sun, 1 Jun 2008 04:19:10 -0700 (PDT), visionset <[email protected]> wrote:

>On 1 Jun, 11:30, rothers <[email protected]> wrote:
>> On Sun, 1 Jun 2008 02:51:54 -0700 (PDT), visionset <[email protected]> wrote:
>> >I've got a Tiagra groupee 52/39 12-23. Although I'm getting much
>> >fitter, I'm not sure the lowest is low enough, for the 1 in 4 & 5
>> >Derbyshire hills I seem to be frequenting. I have to get out of the
>> >saddle, and can't really do that for the length of some of the hills.
>> >Ideally I reckon going to a more compact set up would be best, but I'm
>> >guessing that's a new crank for the less than 39 tooth ring. I still
>> >want to maintain the 'out and out' road racer. I guess the other
>> >option is to maintain the same 8 speeds of the 9 speed cassette and
>> >swap the 23 out for a 25. But then I'm guessing we're in realms of
>> >esoteric cassettes or DIY pin removal? Any decent discussions on
>> >this? Links?
>>
>> On my hybrid I run 105/Ultegra 50/36 12-27 which is about the most I can squeeze
>> out of the lower end without going to a triple and long throw rear.
>>
>> Neil
>
>You can get down to 36 on a standard 130mm PCD crank?, what chainrings
>are these?

Sorry, should have been clearer. I've got 105 derailleurs front and back,
cassette is a Ultegra 12-27 but the chainset is a Truvative Touro 50/36 compact
double with 110mm PCD.

I can just about grind my way up Blaze Hill / Pym Chair with this without
standing up

Neil

 

[Phil Cook]

Pete Biggs wrote:

>visionset wrote:

>> I've got a Tiagra groupee 52/39 12-23. Although I'm getting much
>> fitter, I'm not sure the lowest is low enough, for the 1 in 4 & 5
>> Derbyshire hills I seem to be frequenting. I have to get out of the
>> saddle, and can't really do that for the length of some of the hills.
>> Ideally I reckon going to a more compact set up would be best, but I'm
>> guessing that's a new crank for the less than 39 tooth ring.
>
>38t is the minimum for 130mm.

For some 130mm BCD cranks yes. I have a 7400 Dura Ace crank that had
to be modified to take the chain over a 38 by filing chamfers on the
inside of the arms to let the plates of the chain run low enough to
fully engage the rollers on the teeth.

>I think you would be happier with a compact chainset AND a cassette with a
>bigger big end.

Going for a 13-25 would be a good initial step. A quick look at Wiggle
et al suggests plenty of choice in the 12/13-25/26 range. What these
will tend to do is replace the second lowest with a 23 and then have a
25/26 as lowest rather than have a big jump to the lowest a la
megarange touring setups.
--
Phil Cook looking north over the park to the "Westminster Gasworks"