arlovegreen

Hi there,

I am riding a Vitus 979 that was built up with a Dura Ace RD-7402 8 speed SIS derailleur, cassette, and those purplish 7402 8 speed downtube shifters -- all on a 130mm rear-spaced hub that stretches my rear drop width out . My right hand (rear derailleur) shifter just went slack the other day and I am pretty sure it is blown (the teeth are worn down on the inside). The shifter flops around and can hold the highest and lowest two gears, but nothing inbetween.

I am having problems finding replacement shifters. They go on ebay occasionally and usually end up more than the new 7700 shifters. I hate having my bike out of action and it is a pain to have to wait around to find parts that will work with the 7402 series (which seems to be the hardest to come by).

Should I replace the shifters, cassette, and derailleur with standard, post-1997 Shimano (or other brand) stuff so I can always find spare parts, or should I just hunt down some 7402 shifters and try again? Is this a problem with the 7402 series? Or, should I figure my shifter was a lemon and that my next pair will last a lot longer (I have used a 7400 some 20K miles without a hint of trouble)?

Suggestions or thoughts?
Thanks,
Alan

miamijim

Alan, its NOT a problem specific to the 7402 series.

Before you replace parts can you post a picture of the backside of the shift lever? Are you sure the shift lever boss adapter that slides onto the frame isnt bad?

There are members here who mix and match Pre-'97 Dura Ace witn NON dura Ace and get it to work but that isnt my style. I'd either pay the premium for DT DA 8-speed shifters, use this as an excuse to buy a decent set of STI levers or swap everything to 8-speed Ultegra/105.

RobbieTunes

Been there, switched to 7400 STI's and haven't looked back, or down, for that matter.
Very Smooth. Also ask norskagent.....

Ex Pres 

Any 9s shifter, STI or DT, will work with 8s DA according to SB and BF experience. The STI's not usually as cheap as DT shifters, of course.

dannyg1 

Are the 7402 DT shifter internals mechanically identical/interchangeable with the Ultegra 6400 version? If there's a busted part, the 600 shifters are pretty easy to find.

RobbieTunes

I'll go out on a limb and say yes, as the spacing should be pretty much the same.

I do know the STI versions of the DA 7400 series and 600 tricolor series are almost identical.

They may have different finishes, but internally I have yet to see a difference. Of course, you really can't get into them much. They act the same, too. I'm running one of each, same cassettes, and the only difference is the rest of the bike I'm riding, not the drivetrain.

I tried my DA 9-sp DT shifters with a 7400 8-sp setup. They didn't work very well. Neither did the bar ends, which are supposed to work with either the 7400 (8) and 7700 (9). It could just have been bad mojo, or poor adjustment, or my own great incompetence, but when I finally matched up everything 7400 series, the snafu seemed to evaporate.