Shimano 600 sti problems. Big ones.

grilla

Retro Guru
Hi all

I'm having a bit of a nightmare at the moment with a pair of 6401 shifters. The other day I striped down my everyday bike, with the idea of putting on a tri colour gruppo I had going spare. Everything was going swimmingly, until I realised that the cable housing I thought I had for the gear cables was in fact nowhere to be found, which was annoying. After having bought some housing this week, tonight with much excitement I prepared to finish it off, or so I hoped.

I installed the cables as one should, and went to click through the gears to take up the slackness before making adjustments. The rear mech wouldn't move at all, and the front mech would move up to the big ring but wouldn't click into place; as soon as I took pressure off it sprung back down to the small ring. To much swearing and anguish on my part.

I've already tried googling this, and it seems the general consensus is that if sti's go, they really go, and are nigh on impossible to fix. I've given the moving parts within the levers a good old spray of WD40, but this seems to have done little to help, save for making them feel buttery smooth when moved sidewards. There's a distinct lack of clickiness to the levers, and they seem to have no regular movement as such, but instead a strange and complicated system of different movements and feelings depending on how they feel inclined at that minute.

Needless to say this is incredibly frustrating, and I'm left unsure of what to do. They've definitely worked in the past, and they are definitely installed as they should be, I have double checked the cables for both left and right shifter. Does anybody have any similar experiences?
 
I've just had a bike in with exactly the same problem with some Shimano RSX's. No positive clicking up or down from either lever although sometimes they would randomly work.

A lot of STI's are sealed units and although I've heard of people taking them apart, they're near impossible to get back together. Because their sealed the grease clogs up and dries out inside.

The trick is to turn the bike upside down, get your WD40 can with its straw, push the straw up 'between the back of the brake lever and front the small shifter' and flood it with WD. This is the only point where you can get the WD40 inside the shifter mechanism.

Leave it over night and hopefully next day you'll have perfect shifting :)
 
Right, the old 600s are fussy buggers and need resetting ( left STI to lowest gear and right to highest gear ). This can't be done cable-less and by the way you describe the problem this sounds to be the case ( rear not moving at all so possibly stuck in lowest gear/biggest cog and front only moving a little as it's already stuck in top ). In the case of the right hand one, you need to feed though a cable, pull it with your hand and change UP on the smallest lever. That should sort them out.
 
Hi thanks for the responses. I inverted the bike yesterday and gave it a good soaking, but not between the lever and shifter, so I'll give that a go this morning.

Agency_Scum, the rear mech is stuck in the highest gear/smallest cog, and the front mech is stuck on the small ring. Not sure what difference that makes to your theory?
 
Oooh dear. Not good. That normally is a sign the engaging tooth that hooks on the gear ratchet is worn to buggery. Could mean a strip down which is a psychosis-level event.
 
I can confirm what others here are reporting. Flooding with WD40 or similar has sorted out a couple of early 8 speed type STIs for me.

However, should this not work stripping them down is indeed 'tricky' Its much like dismantling a camera - extremely difficult and likely to end badly unless you know exactly what you are doing. I think there are a couple of how to's somewhere around

Heres one in japanese (Pictures tell an interesting story):

http://tw.myblog.yahoo.com/jimmy63723/a ... &next=9927


Hope you can fix yours.
 
Thanks for the link to the US site. I don't know if I'm quite up for taking apart a shifter myself, particularly considering my Japanese not being up to much!

I don't suppose anyone has a spare pair of 6401s they'd be happy to sell? Condition wise, as long as they function looks are irrelevant :D
 
Back
Top