The trouble with Shimano sti triples?

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mercalia
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The trouble with Shimano sti triples?

Post by mercalia »

I found this article on Shimano triple ( front ) derailleurs that might be interesting



http://janheine.wordpress.com/2013/03/25/trouble-with-sti-triples/
reohn2
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Re: The trouble with Shimano sti triples?

Post by reohn2 »

His logic appears sound.but,I use triple front mechs,Sora/Tiagra/105 and Ultegra(9 and 10sp and 8sp in the past)with 24/34/44.24/36/46.26/34/46.26/34/46 and have used them in the past with 26/34/48.26/36/50.24/38/52 and a variety of chainrings,Stonglight,TA,Shimano,Lasco,FSA.
With 7,8 and 9sp road STI's and friction shifters(DT levers on Kelly's)
I've not had bad or impossible shifting in the way he describes.
I always use ramped and pinned chainrings.
The only time I've experienced bad shifting is when a front mech was so worn it a burr on the inner cage plate and jammed the chain,effectively blocking it from lifting in the way JH describes,it's the only time it's happened.

Edit:- Though TBH a double f/mech may well work OK,if the tooth count from inner to outer isn't too large for it.
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mercalia
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Re: The trouble with Shimano sti triples?

Post by mercalia »

well I thought this might be interesting to give an idea how it is all supposed to work - I had no idea before I by chance came across it what the channel was for in teh back plate. I suppose as aslong as you stick to similar tooth differences as an intended 50-39-30 things might be ok eg my 46-36-26 works fine
pete75
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Re: The trouble with Shimano sti triples?

Post by pete75 »

That article is patently untrue in places - they state "The most common shifting system for triple cranks, Shimano’s STI, only works with Shimano chainrings. " I use it on one bike with an Ofmega triple chainset(Campag copy) and even got STI to work well with an old fashioned Stronglight LX100 chainset after I made pins on the rings with stainless pop rivets. Spa cycles do their standard tourer build with Shimano STI,Sora front and their own XD chainset. They wouldn't do this on a production bike if STI only worked well with Shimano chainrings.
'Give me my bike, a bit of sunshine - and a stop-off for a lunchtime pint - and I'm a happy man.' - Reg Baker
andrewjoseph
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Re: The trouble with Shimano sti triples?

Post by andrewjoseph »

I followed his advice and got a CX front shifter. Absolutely bloody useless.

My wife's triple setup works fine. Mine worked until the shifters broke... Several times.
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foxyrider
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Re: The trouble with Shimano sti triples?

Post by foxyrider »

I use Ultegra FM's with Campag, FSA and cobbled together chainsets with no issue and an ancient 300 FD with Campag has been running for over 10 years.
Front Mechs are the only bit of Shimano i don't get issues with! :lol:
Convention? what's that then?
Airnimal Chameleon touring, Orbit Pro hack, Orbit Photon audax, Focus Mares AX tour, Peugeot Carbon sportive, Owen Blower vintage race - all running Tulio's finest!
ANTONISH
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Re: The trouble with Shimano sti triples?

Post by ANTONISH »

Looks like a sales pitch for Rene Herse chainsets. Actually I've never heard of this company.
mercalia
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Re: The trouble with Shimano sti triples?

Post by mercalia »

pete75 wrote:That article is patently untrue in places - they state "The most common shifting system for triple cranks, Shimano’s STI, only works with Shimano chainrings. " I use it on one bike with an Ofmega triple chainset(Campag copy) and even got STI to work well with an old fashioned Stronglight LX100 chainset after I made pins on the rings with stainless pop rivets. Spa cycles do their standard tourer build with Shimano STI,Sora front and their own XD chainset. They wouldn't do this on a production bike if STI only worked well with Shimano chainrings.



To be fair to the guy I think the spirit of his message was that you can only guarantee that shimano bits will work together on sti ( he is not the first person to say that? ) and he gave what he thought the reasons why ( the point of the post) - if other people make/use rings/chainsets attending to the issues then fine. eg too big a tooth difference between large and middle fouls the grove in the back plate as in his picture? I do remember some one replying to a post I made some time ago about useing a modern front changer with old rsx sti and the guy said he had problems, couldnt get it to work well, but put it down to differnt swing behavior compared to the vintage changer, which really puzzled me.

What I found interesting was his idea that shimano sti controls dont do a full shift but only shift as far as the pins? which then complete the job. I wonder if this is true? And his comments that the location of the pins is not just arbitary & that some non shimano rings may not get this right?
Last edited by mercalia on 27 Oct 2014, 12:06pm, edited 7 times in total.
mercalia
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Re: The trouble with Shimano sti triples?

Post by mercalia »

ANTONISH wrote:Looks like a sales pitch for Rene Herse chainsets. Actually I've never heard of this company.


well he made the comments about Shimano sti because the Rene Herse dont work with Shimano sti? And he wanted to work out why?
mercalia
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Re: The trouble with Shimano sti triples?

Post by mercalia »

andrewjoseph wrote:I followed his advice and got a CX front shifter. Absolutely bloody useless.

My wife's triple setup works fine. Mine worked until the shifters broke... Several times.



thanks for that, thats some thing I dont need to try
flieger114
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Re: The trouble with Shimano sti triples?

Post by flieger114 »

I have a Thorn Audax purchased earlier this year that has a Shimano triple with STI shifters and 48/36/26 chainrings. It is a Deore 105 combination as supplied as standard by Thorn and it works extremely well. So it can be done.
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