Downtube Shifter Problem

[Hendo]

My Shimano downtube shifter for my front derailleur has just started misbehaving and moving too far so it shifts the chain off the largest chainring!

It also now moves past where it used to stop in the opposite direction, which was in line with the downtube.

I've noticed that there seems to be a washer which has split and is now protruding from the shifter, which I'm guessing is the cause of the problem.
Can anyone confirm whether this is likely to be the case, and if so whether these can be got hold of fairly easily? I'd rather man-up and fix it myself, but if it's a pain getting hold of them might just head for the LBS.

 

[Sharky]

You could have a problem with the lever, but it should not affect how far the front mech moves. There is normally two stop screws to stop the mech going beyond where it should.

Keith

 

[Hendo]

Some photos here to help show/explain it, you can make out the washer sticking out on the right of the lever!

 

[fossyant]

Righty, those frame washers are available but may not fit your shifters. What model are they, are they SIS on the rear ? They aren't too expensive for new shifters complete, just bought some for my Ribble.

Might be handy if you can remove the front shifter, and take a picture of the frame washer from the side. Someone here may have spares.

 

[Hendo]

They're SIS on the rear and are Exage 400EX. If possible I'd like to keep them original as poss, as the rest of the bike is original - the guy I bought it from had it from new. Even the Vittoria tyres are from the 90's(!) and amazingly ride really well, although they now need changing - they creaking at the seams....

 

[Hendo]

Meant to say I'll try and get it off tomorrow and post some pictures!

 

[fossyant]

I may have a brand new one available. I just swapped my older 7 speed Ultegra levers for newer 8 speeds. I didn't swap the washers over. I recon one may fit if you can get a side on shot.

The washers are plastic and notched, and I suspect yours has cracked.

 

[Hendo]

Could they be replaced with other 7 speed shifters like 105's or 600's? Won't be original, but period at least!

 

[fossyant]

Could they be replaced with other 7 speed shifters like 105's or 600's? Won't be original, but period at least!

Yes they can.

Even an 8 speed would likely work. 7 speed has a 3.1mm spacer, 8 speed 3.0. I've used 3.0 spacers on 7 speed for years.

You can certainly get any 7 speed shifter to work. I would offer you my Ultegras but the 7 speed shifter was quite worn from use and sloppy on the change.

What's worthwhile considering is getting new 8 speed shifters (they look identical but without the rubber grip which you can swop over) then get some 3.0 spacers for your cassette, just to be 100% sure of a perfect shift. You may need a 1mm spacer on first.

I do doubt you will need the new spacers as the jockey wheel has float, so if set up perfect in the middle, it will only be 0.03 mm out at the end sprockets, which is miniscule.

There are loads of ways round getting Down tube shifters to work well.

I have them on two of my road bikes. Wouldn't change. Both are original.

 

[Alex McCarthy]

Wretched down tube shifters, mine give me no end of trouble. I feel your pain!

 

[Hendo]

Oh dear. Just opened it up and don't think there should be that many pieces.....
The small silver fragment has broken off from the inside of the shifter, and the black washer looks like the least of the problem! Guessing it was just keeping gunk out of the shifter mechanism.
Looks like a new shifter required, what do you guys think?