david kenning said:My sister has twist-grip shifters on her bike and wants to
swap them for 'trigger' type shifters. I said I'd take this
job on for her, but I'm wondering if I'm really up to it -
I've got the Haynes Bike Book to turn to for assistance but
it says nothing about twist-grip shifters so I don't have a
clue how they work.
It's a pretty straightforward job.
Quoted message said:Has anyone got any experience of this kind of job?
Any tips?
Removing the gripshifters will be easy. Undo the cable
securing bolts on both the front and rear mech and pull all
the cables out so that they're just attached to the
shifters. Somewhere on the gripshifts there will be a grub
screw that's holding them onto the bars. Loosen that and
they should just slide off the bars. Obviously you'll need
to remove the grips first.
Getting the cable out of the gripshift can be a bit of a
pain IIRC. Simplest I think would be to remove the cable
casing and get hold of the cable near where it disappears
into the body of the shift. Then push it into the shifter.
The ball end should pop out somewhere.
Quoted message said:How difficult is it to set up the indexing when the new
shifters are installed?
This is a bit of a black art that is learnt by trail and
error. My method is as follows:
Rear mech:
- operate the shifter so it's where it would be on the
smallest cog.
- using the travel screws on the mech adjust the mech so
it's slightly inboard of the smallest cog (in towards
the wheel).
- wind the cable adjuster on the mech out a couple of turns
from fully
in.
- put the cable in and secure.
- adjust the travel screw on the mech so that the mech comes
back into line with the smallest cog. This adjusting of
the travel screw effectively takes up the slack on the
cable for you.
- Now repeatedly shift between the smallest and next
smallest cogs adjusting the cable tension on the adjuster
until it shifts cleanly without you need to over-shift.
- work up the cassette and tweak it so it shifts between
each pair of cogs cleanly.
- it should now shift cleanly over the whole block.
Front mech:
- Similar to the rear, but wind the cable adjuster out on
the shifter because the front mech won't have one. Front
mechs are generally easier to do as they're more tolerant.
Quoted message said:And is it better to fit integrated brake/shift levers or
separates?
My preference is for separates because it means if I break a
brake lever I don't have to replace the whole lot. I can
also run combinations of discs brakes and vees etc without
affecting the shifters.
Quoted message said:Any recommendations for particular make/model of shifters
- Wiggle seem to have a good selection of SRAM and Shimano
stuff but it all looks much of a muchness to me.
My personal preference is always to buy the best you can
afford. At least then it'll last. I suggest if you have
Shimano mechs then you'd be better off with Shimano
shifters. Some of the SRAM shifters will work with Shimano
mechs and vice versa but it'll be a bugger finding out what.
You don't say how many speeds you're after. This will have a
big affect on your selection of shifters as you can't get
top end kit in 7 speed for example and low end kit in 9.
For 7 speed I'd suggest the STX shifters:
wiggle.co.ukwiggle.co.ukOpen ↗
For 8 speed you're a bit stuck with XT shifters:
wiggle.co.ukwiggle.co.ukOpen ↗
or combined Acera or Alivio:
wiggle.co.ukwiggle.co.ukOpen ↗
wiggle.co.ukwiggle.co.ukOpen ↗
For 9 you have more choice, Deore, LX or XT shifters
wiggle.co.ukwiggle.co.ukOpen ↗
wiggle.co.ukwiggle.co.ukOpen ↗
wiggle.co.ukwiggle.co.ukOpen ↗
For brake levers I'd recommend anything by Avid but they
might be a bit on the expensive side. Shimano ones are all
ok and Dia-Compe are also good.
All of the above was written on the assumption it's either a
mountain bike or mountain bike style bike.
HTH
--
"We take these risks, not to escape from life, but to
prevent life escaping from us." bensales.combensales.comOpen ↗