dx shifters - indexed?

[Neil]

For all that the rapidfire plus (push / pull, as opposed to push / push) units are supposed to be better, I've got two bikes using push-push, two that use rapidfire plus. The original push-push have never failed me - the only time I've broken one was due to my own hamfistedness.

Rapidfire plus, from around mid 90s? And in both my examples, Deore LX - both right hand / rear units have either failed, or been revived once, then failed.

Yes, the original DX and above rapidfires weren't perhaps as ergonomic as the late push / pull ones - and perhaps not quite as positive, but at least in my experience, have been more reliable. That said, I've only ever used DX and XT ones, not the LX and below "piano" style ones.

That does colour how I use them, and feel about them. My bikes that have rapidfire plus (Deore LX ones from about 95), have already had the right shifter replaced once, and it seems just a matter of time. My bikes running the DX and XT rapidfire push-push ones? They leave me thinking they'll just carry on working forever (perhaps misguided, but they're already older than the rapidfire plus units, and haven't yet failed, where both of mine have (and yes, temporarily revived by flushing with thin oil, then lubing with a light oil - just delayed the inevitable).

 

[Btypark]

How about ez fire shifters - easy and cheap to get a hold of and perhaps a little better now given that they are still produced by shimano? I think my dx levers are probably beyond redemption from all that has been said by the resident gurus.

 

[FluffyChicken]

Re:

They're not too hard to take apart fully and rebuild. Most parts can be used from all the DX XT XTR until they changed the design with though moulded to the break lever type.

They differ from later designs in that half the ratcheting is in the inside of the barrel and not all on the outside.
But I can take one apart and rebuild quite rapidly now.

The biggest downfall of all these shifter it the plastic cable ring the cable head sits in, it cracks easily and they become useless.

I've taken some pictures of the M900 version (note beefed up top plastic ring and a shorter top ratchet body to compensate, also the return spring in there is slightly different to the DX and XT but can be modified)
https://plus.google.com/photos/11541805 ... v_-EwsLVUg

One of the pics of the internal part.

If you take the covers off and spray WD40 all around it and in where you can. You'll also see a gap right at the top to get to the internal part spray that.
Then clean it up as you can.

A light lube in all the holes and while shifting works nicely as does a spray grease on the outside.


(when they switch they a low profile shifter in the mid-late 90's ,V-brake M739 for example, is when the pawls started to snap.)

 

[Btypark]

Re:

Impressive, most impressive. I might be better to avoid the grief of fixing this only to end up with a broken plastic ring! I would have thought that by fitting newer shimano shifters this shouldn't be a problem, I was thinking the ST-EF 20's. Any opinions either way? Are they cheap muck or a better design than the old boys?

 

[drcarlos]

Re: Re:

They're not too hard to take apart fully and rebuild. Most parts can be used from all the DX XT XTR until they changed the design with though moulded to the break lever type.

They differ from later designs in that half the ratcheting is in the inside of the barrel and not all on the outside.
But I can take one apart and rebuild quite rapidly now.

The biggest downfall of all these shifter it the plastic cable ring the cable head sits in, it cracks easily and they become useless.

I've taken some pictures of the M900 version (note beefed up top plastic ring and a shorter top ratchet body to compensate, also the return spring in there is slightly different to the DX and XT but can be modified)
https://plus.google.com/photos/11541805 ... v_-EwsLVUg

One of the pics of the internal part.

If you take the covers off and spray WD40 all around it and in where you can. You'll also see a gap right at the top to get to the internal part spray that.
Then clean it up as you can.

A light lube in all the holes and while shifting works nicely as does a spray grease on the outside.


(when they switch they a low profile shifter in the mid-late 90's ,V-brake M739 for example, is when the pawls started to snap.)

If you can get them partially apart as fluffy suggests before a full strip try flushing with car brake cleaner and relubing with a light white grease or spray lube. Brake cleaner is quite harsh but will clean off the most stubborn sticky grease (I've used it to clean the sticky old grease from inside sealed freehub bodies) just do it outside over a drip tray with protected eyes.

Carl

 

[millsm]

Re:

I read somewhere years ago that electronic contact cleaner works well. So, decided to try it & it works perfect. Already used it on multiple sets (without taking apart, just spraying into the cable port hole & other areas), and it's dissolved the gunk inside no problem. I'd give them a few flushings, then a spray of light lube (I just use WD-40, but you'd be better off with an actual lube), and all of them still work as new, years later. It's worked on my early-90's DX/XT sets, mid-90's XT/XTR sets, and late-90's XT sets all with the same results. Still have the same can 10 years later

 

[Btypark]

Re:

Wow! Where do I get this magic potion?! Sounds like we should all have a can

 

[FluffyChicken]

Re:

Its just isopropanol in a spray as far as I know, might have a few small quantities of other stuff in it. I mix my own, with a bit of acetone, ethanol and butanol to help out.

But one way is just to loosen the bikt at the bottom a bit and pop in an ultrasonic bath (mines from aldi)
Water an a bit of washing up liquid is all that needed in that.
Give it a scrub with a tooth and brush ratchet it a few times after a few mins, repeat and then rinse in IPA (isopropanol). Then dry.

 

[legrandefromage]

To be fair Fluffy, you've shown pics of the M-95 'Rapid Fire Plus' - the DX are the original 'push push' Sti. They are different inside and not really very easy to dissasemble and reasemble by the average 16 year old at the time, let alone some 24 years later when alcohol and violence could be a factor.

 

[Silvergoat]

Re:

I've got a spare set of those combined dx shifter and lever units, like the examples shown by LGF on the top of the 1st page here. Apart from a few scuffs and scratches, these were only used for a month or so and were replaced with the most excellent 7speed thumbies late '92. Since that time, the combined dx shifters and levers have been dry stored in a big plastic crate of parts. You're welcome to them as I'm never going to use them.