Downtube shifter question

[majorpat]

So I want to buy some Dura Ace 10 sped DT shifters and the website says that I have to use a Dura Ace front derailleur due to "revised cable pull actuation". Was going to use an Ultegra just like with my 9 speed DT's.

True or just marketing baloney?

Thanks.

Pat

[echelon_john]

bologna

[Black Dog]

Total BS, the shifter is friction based. Pull on shifter and FD moves.

[phcollard]

What's been said. I have used dt shifters with almost every kind of Shimano FD, new and vintage, and it has always worked perfectly.

[AgilisMerlin]

i would personally use a Campagnolo fr. der, just for laughs

[majorpat]

Friction, kind of figured it was the same, Shimano hasn't redefined physics yet.

[Louis]

I bet it's a hold-over from the STI version of the text that they didn't delete.

As far as I know every front DT shifter known to man is friction. It would be stupid for it to be anything else.

[kenw]

Itʻs been more than 20 years, so memory is a bit sketchy, but I owned a Trek
1500(?) road bike that had Shimano DT shifters with both index and friction mode.
I think the rear gearing was 6-speed (maybe 7), not that that matters.

[professerr]

I have the same down tube shifters and I've used a Campagnolo Record 10-speed front derailleur as well as an Ultegra. Crankset is 10-speed Record. All worked fine -- actually better than fine, great. I can't see what the problem would be unless there are some Dura Ace downtube FRONT shifters that are not analog/friction.

[kenw]

got in a loop

[professerr]

Itʻs been more than 20 years, so memory is a bit sketchy, but I owned a Trek
1500(?) road bike that had Shimano DT shifters with both index and friction mode.
I think the rear gearing was 6-speed (maybe 7), not that that matters.

I have those and only the rear shifter is index and friction. Front shifter is friction.

[Ti Designs]

Just for laughs, it would be pretty easy to build a micro rotory switch into a set of down tube shifters. I'm guessing the market for DT-Di2 is a rather small one, but you never know...

[Chance]

Friction, kind of figured it was the same, Shimano hasn't redefined physics yet.

It's a good bet Shimano engineers probably know their physics as well or better than most of us.;)

When we mix components with different “cable pull actuation” all it probably means is that we’ll either get a lighter but longer or a heavier but shorter throw. It’s a result of different leverage. Not sure which way it would go in your case without looking up cable pull (assuming there is indeed a difference as stated and is not a misprint). It should work just fine as long as there is enough cable pull to go through entire range, but the “feel” won’t likely match their design. The overall leverage and therefore feel won’t be the same whether we are talking about actuating friction derailleurs or brake calipers (think they revise cable pull there too). That it will work doesn’t mean they are equals. On the other hand you may actually like the feel even more than stock. Or not.

[oldpotatoe]

So I want to buy some Dura Ace 10 sped DT shifters and the website says that I have to use a Dura Ace front derailleur due to "revised cable pull actuation". Was going to use an Ultegra just like with my 9 speed DT's.

True or just marketing baloney?

Thanks.

Pat

Marketing to make you buy the shimano product. Regardless of discussions about pull ratio, 'feel', or anything else. It'll work famously.

[Chance]

Marketing can drive engineering change. Marketing can’t undo actual engineering change. Either there is a difference or there is not. We can’t simply talk it away if there is a difference.

That something works, even if it works well, doesn’t mean it’s not different. That was my only point.

[oldpotatoe]

Marketing can drive engineering change. Marketing can’t undo actual engineering change. Either there is a difference or there is not. We can’t simply talk it away if there is a difference.

That something works, even if it works well, doesn’t mean it’s not different. That was my only point.

I understand but we are talking about a friction front derailleur and a downtube friction shifter. Spring rates, barrel diameter, they can't make any measurable difference if using a ultegra FD or a DA FD.

not rocket surgery.

[Chance]

I understand but we are talking about a friction front derailleur and a downtube friction shifter. Spring rates, barrel diameter, they can't make any measurable difference if using a ultegra FD or a DA FD.

not rocket surgery.

True, although we can make a similar argument about brake levers that look identical from the outside yet some pull as much as twice the amount of cable. Some work great with V-brakes and others much better with cantis or road calipers. Mix them up and the combination may not work great.

You seem certain these shifter components are not very different and hopefully you are right. Personally just think it's prudent to take equipment warnings from the manufacturer seriously until proven wrong.;)

[Louis]

it's prudent to take equipment warnings from the manufacturer seriously until proven wrong.;)

The thing is, the manufacturer and the user don't necessarily have the same priorities.

They want you to buy as much new stuff as possible, hence the "warning." If it were truly a "don't do this, otherwise the system might fail and you might die" warning, then they certainly would not be justified in claiming compatibility issues for front DT shifters.

[keevon]

Just for laughs, it would be pretty easy to build a micro rotory switch into a set of down tube shifters. I'm guessing the market for DT-Di2 is a rather small one, but you never know...

I would totally buy those.

[oldpotatoe]

True, although we can make a similar argument about brake levers that look identical from the outside yet some pull as much as twice the amount of cable. Some work great with V-brakes and others much better with cantis or road calipers. Mix them up and the combination may not work great.

You seem certain these shifter components are not very different and hopefully you are right. Personally just think it's prudent to take equipment warnings from the manufacturer seriously until proven wrong.;)

Not similar at all. I think for things like brakes, safety related, I agree, use what the manufacturer says to use. But IME, downtube shifters and front derailleurs, making sure the DA shifter has a DA front derailleur, like the OP was originally asking..well, it just doesn't matter.

[Ti Designs]

I would totally buy those.

Yeh, but would you drool over them???

[leftyfreak]

Yeh, but would you drool over them???

Would that cause a short, or would you have dealt with that in the prototype phase?

[cachagua]

Some people like to wrap the cable the "wrong" way around the fixing bolt on the front derailleur, to achieve a snappy, short throw at the lever. This would f**k up an indexing system, but with a downtube lever it works fine.

Given that downtube levers can tolerate a deliberate change of cable-pull ratio like that, I'd say "mismatched" is a concept that doesn't apply. I suspect, as someone suggested above, that the caveat is something that never got edited out of the STI manual.