Bicycle Mechanics - Can friction shifter be updated to index?

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clanmacleod
02-11-09, 02:29 PM
I bought my son an Awesome Giant MTB (the model name of the bike, not the primary term I would use :lol:). Its a 24" tire MTB that uses Shimano SIS friction shifters and has a Shimano 70GS rear derailleur, 3 x 6 speed. My 10 yo is having more trouble with the friction shifting than I'd expected.

Its a good fit otherwise. Anyone know if index shifters would work? Right now I've disabled the front shifter to simplify things for him. I don't want to invest a lot into it - ie new chain ring/cogs, but if a simple $30+- shifter upgrade would do it, awesome (that last awesome WAS a descriptor :) ).


Thanks for any advice.

AEO
02-11-09, 02:42 PM
there should be a small loop on the right shifter that says "friction <-> SIS"
simply turn the loop to make the arrow to point to the "SIS" and it's in indexed mode. there should be an audible "click"
Doohickie
02-11-09, 02:56 PM
Yeah.... SIS stands for "Shimano Indexed Shifting" doesn't it?

TimJ
02-11-09, 02:58 PM
I bought my son an Awesome Giant MTB (the model name of the bike, not the primary term I would use :lol:). Its a 24" tire MTB that uses Shimano SIS friction shifters and has a Shimano 70GS rear derailleur, 3 x 6 speed. My 10 yo is having more trouble with the friction shifting than I'd expected.

Its a good fit otherwise. Anyone know if index shifters would work? Right now I've disabled the front shifter to simplify things for him. I don't want to invest a lot into it - ie new chain ring/cogs, but if a simple $30+- shifter upgrade would do it, awesome (that last awesome WAS a descriptor :) ).


Thanks for any advice.

You disabled the front shifter? So is it the front shifter he's having a problem with?

70gs I'm assuming they're thumbshifters, and there's no such thing as an indexing front thumbshifter. You'd have to switch to something like this:

http://cgi.ebay.com/Shift-Lever-MTB-Shimano-Deore-LX-Left-O_W0QQitemZ350104764873QQcmdZViewItemQQptZCycling_Parts_Accessories

If you're talking about the rear then yes, sis means indexing and you should be able to switch to indexing if it's not busted.
JanMM
02-11-09, 04:57 PM
Yeah.... SIS stands for "Shimano Indexed Shifting" doesn't it?

right. (Shimano Index System). if it says SIS then it should be capable of indexing
clanmacleod
02-11-09, 08:20 PM
I feel sheeeeepish! Thank You.