Bicycle Mechanics - front shifter problem

hello,

i recently bought a cheap miyata 110 road bike and noticed it had a rusty front down-tube shifter cable.
i took off the old cable and attached the new one, and now the bike won't stay shifted onto the larger front gear. i can't remember how the lever used to operate, but now it's either forward (parallel with the...down tube?) or you pull it back so it shifts to the big gear, but as soon as you let go of it, it springs forward and then the chain goes to the small gear again. did i put the new wire on too tightly? is there some other adjustment i need to make so the lever stays in the downward (small gear) position?

one thing of note is that when unscrewing the shifter lever, an old brittle fairly thick grey plastic washer fell out and broke to pieces with a hole in it which lookedlike a rectangle that had curved ends, like this drawing but with a top --> (__) and i didnt put it back in because it wouldve been impossible.

is this washer to protect from grime getting into the cable/shift lever mechanism, or is it required so the lever operates properly? how -should- this front gear lever operate? you don't just hold it down and then let it spring back forward again, right? because that seems to just allow you to be on the larger gear while holding it back and would be pointless?

some adjustment/tension help/advice would obviously be appreciated :)

p.s. this bike says suntour trimec on the front derailleur if that helps.

thanks!
-bill

The "washer" is one of the friction surfaces that allows the shift lever to stay in place against the derailleur's spring pressure. You need to replace it or to buy a replacement complete shift lever.

thank you! ill get a new washer right away if i can find one :)

i just thought i'd post a picture of the broken washer i need to replace, in case anyone wonders what is being talked about or might know the name/style/# of washer and if any bike shop, hardware store, or online store might have it in stock:

note: it's stuck to a piece of tape so all the pieces don't go everywhere

well, with this post im now contributing to 80% of the posts for this thread, but i have a question about my shift levers now that i need to replace the washer pictured above (if anyone's still interested):

this miyata 110 road bike has down-tube suntour shifters (ive figured out that much).

ive tried to do research, by using google and searching on here, but i can't figure out whether or not my suntour shift levers (the left one is either up or down, the right one can click into five positions) are indexed or friction, or a combination of both? this bike is from the 70s as many of you probably know.

because the one on the right for the rear clicks, is that indexed?
the left one for the front does just up or down without clicking - is that friction?
are both of mine indexed?
are both friction?

im asking this because if i can't find this particular washer and would have to replace the whole shifter (or shifterS as a set), id like to know what type to get that would work with my derailleurs (id like to keep them down-tube for the heck of it).

im assuming i could probably just use any compatible (friction or indexed, whichever these are) downtube shifters - do i have to specify that the left one needs to have two positions and the right one needs five - matched to the gears?

thanks for everyone's patience and extra thanks to anyone who can explain all this to me.

-bill

p.s. the rear set of gears seems to have six, not five gears, although i thought a miyata 110 was only a 10-speed (and that the miyata 112 was 12)? the right shift lever that i haven't touched (and might also have a rotten washer?) shifts between five of the six rear gears (doesn't reach the smallest one which may be slightly bent and a screw appears to have been adjusted a lot to possibly prevent this gear from being used?) ...i guess this is a separate, but somewhat related question - thanks!

Front (left side) downtube shifters are all friction so any shifter you find will work.

The right side (rear) shifter may be indexed and 5 clicks implies a 6-speed freewheel. Sun Tour did make 6-speed indexed shifting (Accushift was the trade name) that worked reasonably well but replacement parts and matching freewheels are getting very hard to find.

Your inability to reach the smallest cog may be due to bad cable/housing, a damaged rear derailleur, a bent derailleur hanger, an improperly adjusted limit screw or all of the above.