Limitations on triple chainring combinations with STI?



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Rosco

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I'm planning to redo (new paint job + components) an older touring bike that is currently setup with
Suntour 7spd (28-38-48 front 13-30 rear). The bike is used for a variety of things, including having
a Burley Picollo trailer cycle + a 40 lb human ballast attached (they only seem to help pedal when
going downhill). Sometimes a BOB trailer with ~40 lbs of gear are pulled as well. The bike isn't
used for multi-day loaded touring.

After spending too much time looking at gear charts, I'm beginning to believe that a front triple
such as a 24-34-46 in combination with a 9 spd rear 12-23 or 13-25 would allow for a wide range of
usable gears and still give nice close gear ratios. Having a cassette that includes a 16 tooth
sproket seems to make this combination particularly useful. Of course, the rear could be changed to
an 11-32 if I ever needed real low gears as well.

My concern is with the front triple deraileur with STI. Peter White's website suggests that an
Ultegra triple is optimized for a 10 tooth difference between the outer and middle chainrings. In a
similar fashion, he says that Dura-Ace triple is optimized for a 14 tooth difference. His words
suggest there isn't much leaway if STI is desired.

Does anyone have experience breaking these "rules" with success?
 
"rosco" <reverse-the-following"ocsor_g"@hotmail.com> writes:

> I'm planning to redo (new paint job + components) an older touring bike that is currently setup
> with Suntour 7spd (28-38-48 front 13-30 rear). The bike is used for a variety of things, including
> having a Burley Picollo trailer cycle + a 40 lb human ballast attached (they only seem to help
> pedal when going downhill). Sometimes a BOB trailer with ~40 lbs of gear are pulled as well. The
> bike isn't used for multi-day loaded touring.

While we're on it, I'm in a similar situation with my partners beloved old roadster, which has a
Stronglight 48-36 at the front and a Suntour six speed 14-34 at the back. We've already arranged to
have the frame cold set to take a nine speed rear, so I'm not that worried about the rear end.
There's nothing really wrong with the Stronglight that new rings won't cure, but the mech does need
to be replaced, and if we're getting a groupset anyway there's a temptation to replace the lot.

But reading around on the Web I can't seem to find a current, high-quality double-wheel crankset
that will take a 48-36. What am I missing? Can anyone recommend one?

--
[email protected] (Simon Brooke) http://www.jasmine.org.uk/~simon/

Due to financial constraints, the light at the end of the tunnel has been switched off.
 
Originally posted by Rosco
I'm planning to redo (new paint job + components) an older touring bike that is currently setup with
Suntour 7spd (28-38-48 front 13-30 rear). The bike is used for a variety of things, including having
a Burley Picollo trailer cycle + a 40 lb human ballast attached (they only seem to help pedal when
going downhill). Sometimes a BOB trailer with ~40 lbs of gear are pulled as well. The bike isn't
used for multi-day loaded touring.

After spending too much time looking at gear charts, I'm beginning to believe that a front triple
such as a 24-34-46 in combination with a 9 spd rear 12-23 or 13-25 would allow for a wide range of
usable gears and still give nice close gear ratios. Having a cassette that includes a 16 tooth
sproket seems to make this combination particularly useful. Of course, the rear could be changed to
an 11-32 if I ever needed real low gears as well.

My concern is with the front triple deraileur with STI. Peter White's website suggests that an
Ultegra triple is optimized for a 10 tooth difference between the outer and middle chainrings. In a
similar fashion, he says that Dura-Ace triple is optimized for a 14 tooth difference. His words
suggest there isn't much leaway if STI is desired.

Does anyone have experience breaking these "rules" with success?

Go with a MTB FD that more closely matches your chain rings. The arc shape of Ultegra and DURA-ACE mate best with large chain rings in the 52/53 tooth range.
Go with bar end shifters if you can. They are more versatile due to the friction option and your choice of brake levers. They cost less to buy and replace.
 
"Simon Brooke" <[email protected]> wrote in message
news:[email protected]...
> "rosco" <reverse-the-following"ocsor_g"@hotmail.com> writes:
>
> > I'm planning to redo (new paint job + components) an older touring bike
that
> > is currently setup with Suntour 7spd (28-38-48 front 13-30 rear). The
bike
> > is used for a variety of things, including having a Burley Picollo
trailer
> > cycle + a 40 lb human ballast attached (they only seem to help pedal
when
> > going downhill). Sometimes a BOB trailer with ~40 lbs of gear are
pulled as
> > well. The bike isn't used for multi-day loaded touring.
>
> While we're on it, I'm in a similar situation with my partners beloved old roadster, which has a
> Stronglight 48-36 at the front and a Suntour six speed 14-34 at the back. We've already arranged
> to have the frame cold set to take a nine speed rear, so I'm not that worried about the rear
> end. There's nothing really wrong with the Stronglight that new rings won't cure, but the mech
> does need to be replaced, and if we're getting a groupset anyway there's a temptation to replace
> the lot.
>
> But reading around on the Web I can't seem to find a current, high-quality double-wheel crankset
> that will take a 48-36. What am I missing? Can anyone recommend one?
>
> --
> [email protected] (Simon Brooke) http://www.jasmine.org.uk/~simon/
>
> Due to financial constraints, the light at the end of the tunnel has been switched off.

A very beautiful modern double or triple crank is available from Specialites TA called the Zephyr
with a 110 bcd. TA has a number of chainrings, and you can easily do a 48-36. TA has discontinued
the Zephyr, but it's still available here in the US until stock runs out. I believe in the UK, you
have better availability of TA components than we have in the US so you should be able to find one.
TA is replacing the Zephyr with some new products that are pretty much functionally the same, but
less beautiful in some people's eyes. You may also need a new bottom bracket as TA uses a specific
square tapper for their cranks.

FSA also makes a 110 bcd double called the "Carbon-Pro Compact". It comes standard in wither 34-50
or 36-46, but it's very expensive. I remember someone mentioning in this group that FSA is going to
come out with a non-Carbon version of this crank at a lower price. They do this crank in either ISIS
or Octalink interface. I believe Stronglight may also do some 110 bcd cranks, but they don't seem to
import into the US anymore. You might have more luck with Stronglight in the UK. There are several
110 bcd triples to be found as well.
 
"rosco" <reverse-the-following"ocsor_g"@hotmail.com> wrote in message
news:<[email protected]>... .
>
> My concern is with the front triple deraileur with STI. Peter White's website suggests that an
> Ultegra triple is optimized for a 10 tooth difference between the outer and middle chainrings. In
> a similar fashion, he says that Dura-Ace triple is optimized for a 14 tooth difference. His words
> suggest there isn't much leaway if STI is desired.
>
> Does anyone have experience breaking these "rules" with success?

Hi, I'm using a Dura-Ace triple with a Tiagra 30-42-52 crankset and it works fine. The brifters are
Tiagra. Life is Good! Jeff
 
"rosco" <[email protected]> writes:

> A very beautiful modern double or triple crank is available from Specialites TA called the Zephyr
> with a 110 bcd. TA has a number of chainrings, and you can easily do a 48-36. TA has discontinued
> the Zephyr, but it's still available here in the US until stock runs out. I believe in the UK, you
> have better availability of TA components than we have in the US so you should be able to find
> one. TA is replacing the Zephyr with some new products that are pretty much functionally the same,
> but less beautiful in some people's eyes. You may also need a new bottom bracket as TA uses a
> specific square tapper for their cranks.

Excellent suggestion, thanks: it looks beautiful. I think their Vega Light (which looks as if it's
the replacement) is also pretty.

> FSA also makes a 110 bcd double called the "Carbon-Pro Compact". It comes standard in wither 34-50
> or 36-46, but it's very expensive.

Yes, very pretty too, but as you say the price is a bit daunting.

--
[email protected] (Simon Brooke) http://www.jasmine.org.uk/~simon/

Due to financial constraints, the light at the end of the tunnel has been switched off.
 
"daveornee" <[email protected]> wrote in message news:[email protected]...

> Rosco wrote:
> > I'm planning to redo (new paint job + components) an older touring bike that is currently
> > setup with Suntour 7spd (28-38-48 front 13-30 rear). The bike is used for a variety of things,
> > including having a Burley Picollo trailer cycle + a 40 lb human ballast attached (they only
> > seem to help pedal when going downhill). Sometimes a BOB trailer with ~40 lbs of gear are
> > pulled as well. The bike isn't used for multi-day loaded touring. After spending too much time
> > looking at gear charts, I'm beginning to believe that a front triple such as a 24-34-46 in
> > combination with a 9 spd rear 12-23 or 13-25 would allow for a wide range of usable gears and
> > still give nice close gear ratios. Having a cassette that includes a 16 tooth sproket seems to
> > make this combination particularly useful. Of course, the rear could be changed to an 11-32 if
> > I ever needed real low gears as well. My concern is with the front triple deraileur with STI.
> > Peter White's website suggests that an Ultegra triple is optimized for a 10 tooth difference
> > between the outer and middle chainrings. In a similar fashion, he says that Dura-Ace triple is
> > optimized for a 14 tooth difference. His words suggest there isn't much leaway if STI is
> > desired. Does anyone have experience breaking these "rules" with success?

> Go with a MTB FD that more closely matches your chain rings. The arc shape of Ultegra and DURA-ACE
> mate best with large chain rings in the
> 52/53 tooth range. Go with bar end shifters if you can. They are more versatile due to the
> friction option and your choice of brake levers. They cost less to buy and replace.

AFAIK, Shimano MTB front derailers won't work with STI. There's one STI compatible derailer that's
suitable for MTB chainrings -- the RSX. Sheldon Brown has 'em in stock.

Matt O.
 
"rosco" <reverse-the-following"ocsor_g"@hotmail.com> wrote in message
news:[email protected]...
> I'm planning to redo (new paint job + components) an older
touring bike that
> is currently setup with Suntour 7spd (28-38-48 front 13-30
rear). The bike
> is used for a variety of things, including having a Burley
Picollo trailer
> cycle + a 40 lb human ballast attached (they only seem to
help pedal when
> going downhill). Sometimes a BOB trailer with ~40 lbs of
gear are pulled as
> well. The bike isn't used for multi-day loaded touring.
>
> After spending too much time looking at gear charts, I'm
beginning to
> believe that a front triple such as a 24-34-46 in
combination with a 9 spd
> rear 12-23 or 13-25 would allow for a wide range of usable
gears and still
> give nice close gear ratios. Having a cassette that
includes a 16 tooth
> sproket seems to make this combination particularly
useful. Of course, the
> rear could be changed to an 11-32 if I ever needed real
low gears as well.
>
> My concern is with the front triple deraileur with STI.
Peter White's
> website suggests that an Ultegra triple is optimized for a
10 tooth
> difference between the outer and middle chainrings. In a
similar fashion,
> he says that Dura-Ace triple is optimized for a 14 tooth
difference. His
> words suggest there isn't much leaway if STI is desired.
>
> Does anyone have experience breaking these "rules" with
success?
>
>

We're currently running an FDR designed for 52-42-30 with an RSX 46-36-26 crankset on my wife's
bike. It helped, though, to grind the outer cage to the curve of the 46. The only problem I had with
this setup is that the bike has a large - 1 3/8" - seat tube, so I had to change the length of the
BB to get the shifting to work well.

If you have a 28.6mm/1 1/8" or 31.7mm/1 1/4" seat tube, you might want to try an early RSX model
FD-410 top swing FDR, which is designed for a 46-36-26 setup.

And you're right that a 46-36-26 with 12-25, or something similar, makes a lot of sense for
recreational road use. I believe Sheldon Brown/Harris Cyclery still has Sugino
110/74mm BCD cranks with 46-36-26 rings available
 
"rosco" <reverse-the-following"ocsor_g"@hotmail.com> wrote in message
news:<[email protected]>...
> I'm planning to redo (new paint job + components) an older touring bike that is currently setup
> with Suntour 7spd (28-38-48 front 13-30 rear). The bike is used for a variety of things, including
> having a Burley Picollo trailer cycle + a 40 lb human ballast attached (they only seem to help
> pedal when going downhill). Sometimes a BOB trailer with ~40 lbs of gear are pulled as well. The
> bike isn't used for multi-day loaded touring.
>
> After spending too much time looking at gear charts, I'm beginning to believe that a front triple
> such as a 24-34-46 in combination with a 9 spd rear 12-23 or 13-25 would allow for a wide range of
> usable gears and still give nice close gear ratios. Having a cassette that includes a 16 tooth
> sproket seems to make this combination particularly useful. Of course, the rear could be changed
> to an 11-32 if I ever needed real low gears as well.
>
> My concern is with the front triple deraileur with STI. Peter White's website suggests that an
> Ultegra triple is optimized for a 10 tooth difference between the outer and middle chainrings. In
> a similar fashion, he says that Dura-Ace triple is optimized for a 14 tooth difference. His words
> suggest there isn't much leaway if STI is desired.
>
> Does anyone have experience breaking these "rules" with success?

Campagnolo Ergo levers. I have a Sugino XD 26-36-46 and an XTR front derailleuer. The left-hand Ergo
lever is closer to friction shifting than STI --it has a series of detents, but spaced close enough
that you can use a wide range of cranks and derailleurs. For a while I used an Ergo lever on the
left and a Dura-Ace lever on the right. Now I have an ergo lever on the right, but kept my Shimano
hubs and cassettes. For the ways to make that work, see:

http://www.hearingoffice.com/download/hearing/10_Speed_Conversion_print.pdf
 
"Grenouil" <[email protected]> wrote in message
news:eek:[email protected]...
> "rosco" <reverse-the-following"ocsor_g"@hotmail.com> wrote in message
> news:[email protected]...
> > I'm planning to redo (new paint job + components) an older
> touring bike that
> > is currently setup with Suntour 7spd (28-38-48 front 13-30
> rear). The bike
> > is used for a variety of things, including having a Burley
> Picollo trailer
> > cycle + a 40 lb human ballast attached (they only seem to
> help pedal when
> > going downhill). Sometimes a BOB trailer with ~40 lbs of
> gear are pulled as
> > well. The bike isn't used for multi-day loaded touring.
> >
> > After spending too much time looking at gear charts, I'm
> beginning to
> > believe that a front triple such as a 24-34-46 in
> combination with a 9 spd
> > rear 12-23 or 13-25 would allow for a wide range of usable
> gears and still
> > give nice close gear ratios. Having a cassette that
> includes a 16 tooth
> > sproket seems to make this combination particularly
> useful. Of course, the
> > rear could be changed to an 11-32 if I ever needed real
> low gears as well.
> >
> > My concern is with the front triple deraileur with STI.
> Peter White's
> > website suggests that an Ultegra triple is optimized for a
> 10 tooth
> > difference between the outer and middle chainrings. In a
> similar fashion,
> > he says that Dura-Ace triple is optimized for a 14 tooth
> difference. His
> > words suggest there isn't much leaway if STI is desired.
> >
> > Does anyone have experience breaking these "rules" with
> success?
> >
> >
>
> We're currently running an FDR designed for 52-42-30 with an RSX 46-36-26 crankset on my wife's
> bike. It helped, though, to grind the outer cage to the curve of the 46. The only problem I had
> with this setup is that the bike has a large - 1 3/8" - seat tube, so I had to change the length
> of the BB to get the shifting to work well.
>
> If you have a 28.6mm/1 1/8" or 31.7mm/1 1/4" seat tube, you might want to try an early RSX model
> FD-410 top swing FDR, which is designed for a 46-36-26 setup.
>
> And you're right that a 46-36-26 with 12-25, or something similar, makes a lot of sense for
> recreational road use. I believe Sheldon Brown/Harris Cyclery still has Sugino
> 110/74mm BCD cranks with 46-36-26 rings available
>
>

Yes, of course - the RSX is my answer if going STI. The seat tube is 28.6, so that should work out
fine. If I go with bar end shifter, I guess the whole lot of MTB FDRs are fair game. MTB's always
seem to have 12 tooth differences between the outer two rings, and a 22 tooth max, so 24-34-46 would
seem to work fine.
 
On Mon, 13 Oct 2003 05:04:33 GMT, "rosco" <reverse-the-following"ocsor_g"@hotmail.com> wrote:

>After spending too much time looking at gear charts, I'm beginning to believe that a front triple
>such as a 24-34-46 in combination with a 9 spd rear 12-23 or 13-25 would allow for a wide range of
>usable gears and still give nice close gear ratios. Having a cassette that includes a 16 tooth
>sproket seems to make this combination particularly useful. Of course, the rear could be changed to
>an 11-32 if I ever needed real low gears as well.

Your ideal derailleur would be a pre microdrive model. Cambria Bike has something for sale that they
claim would work perfectly with your choice.

An Ultegra front derailleur should be ok if your large chainring is a
48. I use a 105 front and it shifts a 48/34 perfectly. Should you be looking for an Ultegra triple
front, I have one for sale for $33.
 
On 13 Oct 2003 08:15:18 -0700, [email protected] (Jeff Starr) wrote:

>Hi, I'm using a Dura-Ace triple with a Tiagra 30-42-52 crankset and it works fine. The brifters are
>Tiagra. Life is Good!

I had poor success with that combination. The front derailleur had to be more than 3 mm above the
52. It just made it using a 53t ring. The DA front derailleur would be much happier with 52/40/30.

I didn't ride my DA triple front and it is for sale for $45 obo.
 
On Mon, 13 Oct 2003 13:08:21 -0500, "Grenouil" <[email protected]> wrote:

>And you're right that a 46-36-26 with 12-25, or something similar, makes a lot of sense for
>recreational road use. I believe Sheldon Brown/Harris Cyclery still has Sugino
>110/74mm BCD cranks with 46-36-26 rings available

If you use a 24t ring and the small range cassette like a 12/23 or 25 and a road front derailleur,
there is a good chance that you will drag the chain on the bottom cross piece of the front
derailleur in the smaller cogs.
 
"rosco" <reverse-the-following"ocsor_g"@hotmail.com> wrote in message

> My concern is with the front triple deraileur with STI. Peter White's website suggests that an
> Ultegra triple is optimized for a 10 tooth difference between the outer and middle chainrings. In
> a similar fashion, he says that Dura-Ace triple is optimized for a 14 tooth difference. His words
> suggest there isn't much leaway if STI is desired.
>
> Does anyone have experience breaking these "rules" with success?

My Heron Road uses Campy Ergo shifters with an Ultegra triple front derailer shifting a 110/74 BCD
crank - 24-36-50 rings - no ramps or pins on the rings and a 9 spd. 12-21 cassette. The Campy
"semi-indexed" front shifter manages this shift just fine and I've had no issues with the F
derailer. System works great and I wish I had gone Campy instead of Ultegra when I built up my
Lemond Ti this past spring.

Not sure how all this would work with STI brifters, but I hate STI anyway......

SB
 
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