10 speed triple 48-36-26 ?

[Manc33]

The biggest range I ever got away with was a 52-38-24 chainset using those Spa T6/7075 chainrings. This was shifted by a R773 front mech (they make a 50t and a 52t specific version of those mechs) and it actually shifted well. All with 11-32t at the rear. The funny thing is that triple FD was setup on a MTB shifter when it should be with flat bar shifters, which seem to have a unique pull ratio (?).

It worked, but only if I had the cable deliberately too loose when on the granny ring, which I didn't care about because it did work. I even debated putting a 53t on but never did it.

I have never had gearing that good before or after! I went MTB a bit ago and because I want a chain guard on, never bothered going to a 52t outer again. I don't think there's a 104 BCD outer thats 52t and can be fitted with a chain guard. MTB just doesn't cater for chainrings like that afaik. Just settled for a 48t in the end. Whats -4t on an outer when you have 11t at the back. About one road gear.

[NetworkMan]

That tends to tie in with a point I was trying to get across on another thread; that so long as the RD can cope with the capacity and the chain doesn't hit the bottom of the FD, then the small ring can be pretty much as small as you like. I happily run 48/38/24. Generally the chain can go slack in the two highest gears on the little ring since you shouldn't use them anyway and I guess you might have had that issue with such a wide range on the front.

[cycleruk]

105 left STI will have a cable pull of about 12mm per chainring. (ie to move from one ring to the next.)
LX front dérailleur needs 19mm of cable pull to do the same move.
So road STI systems do not match MTB front dérailleurs with out some modification.
You can use a road FD with MTB chainsets if you can move the FD outwards to match the chainline.
Chainline:- https://www.sheldonbrown.com/chainline.html

Shimano Road chainline = 45mm
Shimano MTB chainline = 47.5 to 50mm.
So initially moving a road FD outwards by 2.5 to 5mm should work O.K.
But thought has to be taken that the curve and profile of the FD matches the ring choice.
Also because you are using smaller MTB rings you can only lower the FD so far before it clashes with the chainstay.

[Paul Smith SRCC]

Can I get this discussion back on track rather than continue the pre-historical cycling theme please

For those of you running a 9 speed crankset (e.g. 48-36-26)/FD with 10 speed 105 STIs - could I ask if there's a problem with adjusting the front derailleur to overcome chain rubbing for the extreme gears of the rear cassette (I'm thinking 11-32 to give a bottom gear of 21 inches)?

My LBS is suggesting 10 speed 105 STI/RD with 9 speed LX FD and crankset though they have warned there may be some chain rubbing (on up to 3 gears). They don't seem too keen on the Stronglight route (perhaps they've read the Neanderthal descriptions in this thread ) Incidentally, the BB on the VN Yukon is a standard 68mm English thread.

The alternative is to keep to 9 speed as some of you have suggested.

Thanks again for your responses.

A longer 105 rear mech' will cope with 32t but it will struggle with a triple set up, a quick search came up with

Maximum Low Sprocket: 30T (short) / 32T (med) with double chainset
Maximum Front Difference: 16T, total capacity 34T (short) / 22T, total capacity 40T (med).

At the time 10 speed 105 STI was current a common mix and match for use with a triple (even 105 triple as the 105 rear mech' max did not got to 32t, IIRC it was 27 then later 28t) was to fit a Deore M591 rear mech', although 9 speed it worked with the 10 speed 105 STI shifters. Mix and matching can be a lottery, the subsequent generation of the Deore mech' did not mix and match anywhere near as effectively. The Deore M591 should be quite easy to track down, some stores may still have, if not auction sites like ebay.

[Brucey]

105 left STI will have a cable pull of about 12mm per chainring. (ie to move from one ring to the next.)
LX front dérailleur needs 19mm of cable pull to do the same move.
So road STI systems do not match MTB front dérailleurs with out some modification.
You can use a road FD with MTB chainsets if you can move the FD outwards to match the chainline.
Chainline:- https://www.sheldonbrown.com/chainline.html

yup

Shimano Road chainline = 45mm
Shimano MTB chainline = 47.5 to 50mm.
So initially moving a road FD outwards by 2.5 to 5mm should work O.K.
But thought has to be taken that the curve and profile of the FD matches the ring choice.
Also because you are using smaller MTB rings you can only lower the FD so far before it cashes with the chainstay.

(my italics) well it often does but not perfectly and not always; the shift ratio of a typical shimano road triple FD changes dramatically through the stroke and some won't even reach far enough (which -amongst other things- depends on the diameter of the seat tube and how the FD is designed). It is just yet another excuse that an already finicky system has to not work properly.

If you want to use road STIs with any non-standard triple chainset the things to shoot for (if you want the best chance of trouble-free installation) are to

- use a road triple FD
- use the road triple FD at a road chainline
- preserve the ring interval (between middle and outer) very closely, (even if the chainrings are a bit smaller all round)

If these things do not apply you can tilt the balance of probabilities in your favour in various ways eg by using a FD with an oversize band mount and an eccentric shim; this will bring the FD closer to its intended position (vs a chainset with a different chainline) and it will work better with STIs.

Another bodge/modification that can work in some cases is to use an MTB FD (on a MTB chainset) but to alter the shift ratio of the FD by revising the cable mount. This isn't readily possible with all MTB FDs and it doesn't always work well enough either.

Personally I'd rather eat worms than use a MTB chainset on a road bike; the Q values are about 40mm larger than the chainsets I like, but each to his own.

Note that some of the possible variations in setup may involve the FD being unusually strained against the high gear limit screw when the big ring is selected; this is exactly the sort of thing that causes some LH STIs to fail in short order.



cheers

[scottg]

Sugino Alpina 10s Triple, square taper, the latest innovation in weather resistance.

Campag 10s Ergos, with the IRD Alpina front mech or the Campaq triple front mech,
both work fine. Plan B would be a Suntour bar-con for front shifting.

https://www.suginoltd.co.jp/us/products ... pina2.html

http://www.interlocracing.com/shifters- ... derailleur

[The utility cyclist]

I use a TA Carmina, I get exactly the ratios I am after but at a cost, both financially and how well the set up works.

Deciding what ratios you want is a large enough topic in itself. To highlight what I referenced in my own review of that chain set with Campagnolo 10 speed, all fitted back in 2007 and what was a specification available at the time "I have chosen 26/36/46 with a 13-29 cassette as it gave me a reasonably high top gear as well as a set of useable low gears that should get even an unfit me up most climbs (mid 90” top with most wheel tyre combinations and high 20” low). It was not just about how low and high the extremes were, just as important is that the most often used gear ratios are available where chain line is as straight and therefore as smooth as possible, making the whole transmission also last longer as a result".

Financially yes I treated myself, but I also had trouble getting the front mech' to work efficiently as the radius of the mech' follows a larger chainring radius, it works well enough for me personally, but that maybe not well enough for others.

I used a 400LX front mech with 5603 STIs and it shifted superbly using a Stronglight Impact 48/36/26 (despite someone on here questioning how well it shifted )
Campagnolo did make an ATB/MTB groupset in 10 speed with their own flat bar shifters, I had one on a bike last year, here's a front mech https://www.ebay.co.uk/itm/NEW-NOS-CAMP ... SwvkZblZlK not sure if that would work with the very latest Campagnolo Ergos but the older variants with the multiple micro shifts on he ratchet would work a treat for a campag system and smaller large c/ring.

[Manc33]

Got mine setup running the 6503 front mech + 6510 shifters + 48-36-22 triple on a MTB with a Problem Solvers Cross Clamp & Pulley (what a godsend), with a 11-34t and it's shifting alright. I was going to keep my chain catcher on but, now I have gone to a 45mm chainline, the frame itself looks like it should stop the chain if it drops, which is just as well because the chain catcher simply cannot be fitted there, it was a squeeze on a 50mm chainline. Also the 48t outer is about 4mm away from the chainstay, but I don't care.

Going to a 45mm chainline has also let me screw more threads of the drive side BB cup in, since it's two 2.5mm spacers are now gone. I always thought it was a bit daft how they are sandwiched between the BB shell and the BB cup. All those threads going to waste lol. To make the Hollowtech 2 spindle even out properly for the preload cap, I then put 5mm worth of spindle spacers (another godsend) on the outer of the left BB cup, so it's all spaced how it was. Full steam ahead.

[landsurfer]

FSA do a 48-36-26 ... Got one on my Jamis framed thing. Nice chainsets ... But black ....

[Manc33]

FSA do a 48-36-26 ... Got one on my Jamis framed thing. Nice chainsets ... But black ....

The Alivio T4060 (about £50 new) is available in 48/36/26, then it's just a case of swapping the 26t off and putting a 22t on. I also like it because it has got a chain guard, which saves tucking pants in socks.

I just wanted a chainset that was HT2 and could have the chainrings replaced, That Alivio T4060 was the cheapest I could find. Even cheaper ones are riveted, *hand wave dismissal*.

[The utility cyclist]

FSA do a 48-36-26 ... Got one on my Jamis framed thing. Nice chainsets ... But black ....

FSA Metropolis Urban?

[pedalsheep]

Sugino Alpina 10s Triple, square taper, the latest innovation in weather resistance.

Campag 10s Ergos, with the IRD Alpina front mech or the Campaq triple front mech,
both work fine. Plan B would be a Suntour bar-con for front shifting.

https://www.suginoltd.co.jp/us/products ... pina2.html

http://www.interlocracing.com/shifters- ... derailleur

Has anyone in the UK tried the alpina front derailleur linked by scottg? For years I ran a Carmina 26/36/46 chainset with 9 speed campag and it all worked beautifully. After 87,000 miles the mechs and shifters were worn and so I 'upgraded ' to 10 speed Veloce shifters and front and rear mechs but just can't get the front mech to play nicely. Wondering whether to try the alpina mech or give up and try to hunt out some 9 speed stuff.

[pedalsheep]

I use a TA Carmina, I get exactly the ratios I am after but at a cost, both financially and how well the set up works.

Deciding what ratios you want is a large enough topic in itself. To highlight what I referenced in my own review of that chain set with Campagnolo 10 speed, all fitted back in 2007 and what was a specification available at the time "I have chosen 26/36/46 with a 13-29 cassette as it gave me a reasonably high top gear as well as a set of useable low gears that should get even an unfit me up most climbs (mid 90” top with most wheel tyre combinations and high 20” low). It was not just about how low and high the extremes were, just as important is that the most often used gear ratios are available where chain line is as straight and therefore as smooth as possible, making the whole transmission also last longer as a result".

Financially yes I treated myself, but I also had trouble getting the front mech' to work efficiently as the radius of the mech' follows a larger chainring radius, it works well enough for me personally, but that maybe not well enough for others.

When you say you had trouble getting the front mech to work efficiently could you elaborate please? I am running the same set up but with Veloce shifters and mechs and having great difficulty getting the front mech to work efficiently. What compromises did you accept in the end?

[Paul Smith SRCC]

I use a TA Carmina, I get exactly the ratios I am after but at a cost, both financially and how well the set up works.

Deciding what ratios you want is a large enough topic in itself. To highlight what I referenced in my own review of that chain set with Campagnolo 10 speed, all fitted back in 2007 and what was a specification available at the time "I have chosen 26/36/46 with a 13-29 cassette as it gave me a reasonably high top gear as well as a set of useable low gears that should get even an unfit me up most climbs (mid 90” top with most wheel tyre combinations and high 20” low). It was not just about how low and high the extremes were, just as important is that the most often used gear ratios are available where chain line is as straight and therefore as smooth as possible, making the whole transmission also last longer as a result".

Financially yes I treated myself, but I also had trouble getting the front mech' to work efficiently as the radius of the mech' follows a larger chainring radius, it works well enough for me personally, but that maybe not well enough for others.

When you say you had trouble getting the front mech to work efficiently could you elaborate please? I am running the same set up but with Veloce shifters and mechs and having great difficulty getting the front mech to work efficiently. What compromises did you accept in the end?

I actually wrote a more extensive review of that set up if you are interested (click for link). But in answer to "What compromises did you accept in the end?"

To repeat what I referenced in my write up, the "mech line does not follow the chain ring’ so the mech’ pushes the chain too far away from where the chain disengages the chain ring. This can and in this case does mean that you don't get such good gear change, more noticeably when changing into the smallest ring. I have got it working just good enough for me, but it is definitely a compromise, I try not to change down under full pressure and if possible not when in the largest rear sprocket, I get a better shift if I am in 3-4th sprocket down as the mech' engages the chain nearer where it was designed to do, as a precaution I have also fitted an ’Overshift Protector’. Worth bearing in mind that each individuals perception as to what is and what isn't acceptable interms of the compromises that need to be made will naturally vary. My own conclusion is that I am prepared to 'fettle' some of the gear changes and sacrifice efficient shifting to achieve the ratios I want, justifiably others conclude that they would rather have the gears work as they should, at the expense of not having quite the ratios they desire."

Hope that helps?

[Brucey]

FWIW those chainrings have pins and ramps to help upshifts but not much to help downshifts. Obviously it won't help exactly but I don't think the problem with the downshifts is entirely confined to the fit of the FD to the chainrings.

If you fit a braze-on type FD on a modified adaptor (eg with a wedge in it) you can get the FD to fit the chainrings better and this will help. However different chainrings, with downshift gates, and/or different chains/chainrings (eg chains that have different side plates, chainrings that have slightly different width teeth vs the internal width of the chain) can make a big difference to the downshift quality too.

IME even teeth that are 0.1mm wider than is ideal (for the chain in use) can completely wreck the downshift performance.

cheers