I've inherited this good old italian steel frame bike and the front derailleur doesn't lock in place when shifting to the bigger chainring. As you can see in the video the derailleur can shift the chain into the largest chainring but when you release the shifter the derailleur just returns to low position.
How would you tackle this?
I have some experience and tools, hope this is not something too hard.
Thank you!
Shimano (old) 105 front derailleur not clicking into place
byu/Scott_Korman inbikewrench
by Scott_Korman
4 Comments
Sometimes you just gotta hose out the shifter with some spray lubricant. Not WD40… But sometimes WD40 🤷
Actually WD40 works well because it’ll break down the gummy old lubricant that’s causing the sticking. Then if that works, after a few days I’ll put a few drops of chain lubricant in there because it’ll stick around longer.
I’d detach the derailleur cable from the derailleur and then see if u can shift the shifter over and listen for the click. If it doesn’t click with no tension on it the ratcheting mechanism in the shifter is probably dead. Good news is you can probably find a used one on eBay for like $10-20
You’d need new bar tape likely, unscrew the old shifter and slide it off, slide on the new one. The cable can be pulled from the shifter when it’s in the small chainring position, you’ll have to find it though it’ll be underneath the cover / shifter. You can push the cable from the cable guide where the shifter goes down the seat tube to push it out. Probably can reuse the cable but new one is only like $3-5 from the bike shop
There’s a pawl in the shifter that makes the clicking happen and “grabs” the ratcheted wheel which the cable sits in. The pawls often get stuck out/open in old, dry grease and then the clicking stops. Usually, if you spray a solvent/lube (I recommend one-step from finish line – industry standard for this) it will free up after actuating the shifter. If it still doesn’t free up, you can take things apart a little, find the pawl, and wiggle it with a pick while spraying it directly with the solvent (make sure to lubracate after if not using one-step).
Sometimes it takes a while, but I’ve never seen a shifter fail to free up with enough work. I do this every day (I work at a bike shop that refurbishes bicycles). Your shifter isn’t dead, just needs love.
Flush with solvent/degreaser. Be patient and actuate often. This is a common Shimano problem, but relatively easy to solve. Some are more stubborn than others, but I would not engage in disassembling the shifter until I was ready to give up otherwise. Good luck! You got this.