setting up triple front mech - no barrel adjuster

keef66

Scott CR1 frame, swapping all the kit from my Racelight. Got the 105 triple chainset to fit only after filing off the inner projections on the 30t chainring. Everything else has transferred nicely, even the long drop brakes work with the blocks slid right to the top of their slots. Rear indexing is spot on, but I cannot for the life of me get the front mech to work properly.

Followed the Shimano instructions to the letter, but I cannot get it to shift easily into the big ring, and if it does, the cable tension feels way too high and I fear for the shifter. If ever I do get it to work, the Shimano instructions suggest fine tuning using a frame mounted barrel adjuster, which the CR1 lacks. Do I need to buy an inline one?

desweller

It will make life easier.

I prefer to open the top limit screw right out when I'm setting up. I wedge the derailleur into the middle position with a piece of wood and set the shifter to the bottom ring trim position or the bottom position (this is because I can't get as much tension on the cable as the derailleur spring). Pull the cable as tight as I can and clamp up. Then I adjust the tension to give reliable shifting before closing the top screw back down to avoid overshifting.

Jimfrandisco

DesWeller - interested to hear that technique, if usually have the mech in the small ring/low position and pull cable tight and clamp which usually means still having too much slack in the cable - but what you sounds like it compensates for that.
One thing though - why opening up the top limit screw, can't see how that makes a difference?
cheers
Jim

Bozman

I've just built the same frame up and I just installed an inline barrel adjuster, I had to do the same on my Izalco and it comes in useful and saves a lot of sh*t.

desweller

If the top limit screw is wound in too far to begin with, it stresses the mechanism of the shifter if you try to drive it into top gear. I prefer to wind it out and then use it to tune the shifter overtravel point rather than risk loading the shifter against it in the final shifted position.

I hope this makes sense, I'm struggling to think of a good way of describing it.

Jimfrandisco

Yep, makes sense - can see the logic in that.
building a bike up next week which will be a triple so may give your technique a go.
cheers

onbike 1939

Road triple FDs are always a pig to set-up and an In-line adjuster is essential in my view as at some time you will have to take up the cable tension. Make sure that the outers are cut square as they enter the adjuster. In my experience if you are to avoid the outer ends fraying at the adjuster, it's essential to go to the small ring before making an adjustment. It appears that the tension on the outer is responsible for forcing back the plastic covering.