Making a ghetto 'sub compact' out of an old triple
03-07-19, 02:42 AM
#1
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Making a ghetto 'sub compact' out of an old triple
Anyone done this?
i need lower gearing on my commuter (currently 46/36).
I have an old 52/42/30 triple and BB sat here. Could I take off the big ring, swap in some singlespeed bolts and ride it as a 42/20?
Would I need a triple FD - I fear the current FD might not go inboard enough for the granny ring.
I'd be delighted to hear from anyone who's attempted this.
currently running an 11-30 cassette, and I am aware I could go 11-34.
Thanks in advance!
i need lower gearing on my commuter (currently 46/36).
I have an old 52/42/30 triple and BB sat here. Could I take off the big ring, swap in some singlespeed bolts and ride it as a 42/20?
Would I need a triple FD - I fear the current FD might not go inboard enough for the granny ring.
I'd be delighted to hear from anyone who's attempted this.
currently running an 11-30 cassette, and I am aware I could go 11-34.
Thanks in advance!
03-07-19, 04:39 AM
#2
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I wouldn’t call it ghetto. But yes it has been done. MTB front derailleurs work well seeing as that’s what they’re designed for. You could just use the triple and adjust the limit screws so you don’t overshift. Lots of folks are using a bash guard in place of the big ring.
03-07-19, 07:38 AM
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Bash guard/36/22 with triple FD here. Works great on my commuter and my gravel bike. With one less ring, chain wrap is not an issue and you can go to a wider cassette.
I agree with cs1 - adjust the limit screws and go.
I agree with cs1 - adjust the limit screws and go.
03-07-19, 08:02 AM
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Your old 52/42/30 triple most likely has a 74 mm granny ring bolt circle and the smallest chainring that will fit is 24T.
03-07-19, 12:12 PM
#5
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a Beauty..
very non ghetto, but very Italian , in the 80s I got a triple, Campagnolo type inner 36, Middle 52 (outer flipped over,
a GS, they don't have a pin to go behind the crankarm..
and a <C> polished Disc Cross Chainguard .. big chain ring centered on chainline...
Will Sell ...
a GS, they don't have a pin to go behind the crankarm..
and a <C> polished Disc Cross Chainguard .. big chain ring centered on chainline...
Will Sell ...
03-07-19, 04:52 PM
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I'm doing the same. I have a Sugino crank that was a 50-40-30 and it's currently a 50-40-26. I'm on the search for a vintage-looking ring/bash guard to replace the 50. The front derailleur is a '90s Shimano 105 designed for a triple.
03-07-19, 09:59 PM
#8
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I run a mtb crank on my road bike (old Suntour 42/32/22) with the 22 chainring removed and the lugs for the 22 chainring also ground off. Bottom bracket is narrower (110 or 113 I think) to bring the crank closer to the frame. Uses road fr derailleur and shifts fine.
03-07-19, 11:08 PM
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I have a similar setup on my cargo bike: 24/36/bashguard. Low gear is 24-34... good if you want to tow a Chevy to the junkyard.
Front derailleur setup gets a little weird with very small "big" chainrings.
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