Truvativ by SRAM, IsoFlow road triple 52/42/30T crankset
06-03-22, 11:49 PM
#1
Junior Member
Thread Starter
Truvativ by SRAM, IsoFlow road triple 52/42/30T crankset
This crank is OEM on a Fuji Absolute 2.0 from 2010. (27 speed bike)
The 42t chainring needs replacement.
Who carries just a NEW 42?
I see SRAM has a TruVativ section on their web site. But there is no direct replacement for this set or its parts…only used stuff from eBay.
The 42t chainring needs replacement.
Who carries just a NEW 42?
I see SRAM has a TruVativ section on their web site. But there is no direct replacement for this set or its parts…only used stuff from eBay.
06-04-22, 12:27 AM
#2
Guest
Join Date: Sep 2020
Posts: 2,888
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 1346 Post(s)
Liked 3,270 Times
in
1,439 Posts
Figure out the BCD, then shop for 42T chainrings that match it. It's a common size, and any one with ramps/pins should work.
Likes For Rolla:
06-04-22, 12:34 PM
#4
Junior Member
Thread Starter
I am aware of the BCD metric. But I've never had to actually use it before in searching for a ring. E.g., for my Gary Fisher 21 speed, which uses a 7-speed chain, I just Google: "Shimano 32T chain ring". And the first page of links are always correct. E.g. https://www.amazon.com/Shimano-M590-.../dp/B007HOGXIU
For the Fuji, the question is: for the topical triple 52/42/30T crankset , is there a common form factor (for plug-n-play) among manufs. AGAIN: Just the chainring -- not the whole crankset.
BTW:
HUH ???
For the Fuji, the question is: for the topical triple 52/42/30T crankset , is there a common form factor (for plug-n-play) among manufs. AGAIN: Just the chainring -- not the whole crankset.
BTW:
You know the story, check for chain stretch yadda yadda
06-04-22, 02:50 PM
#5
Senior Member
Join Date: Oct 2014
Location: Portland, OR
Posts: 12,890
Bikes: (2) ti TiCycles, 2007 w/ triple and 2011 fixed, 1979 Peter Mooney, ~1983 Trek 420 now fixed and ~1973 Raleigh Carlton Competition gravel grinder
Mentioned: 129 Post(s)
Tagged: 0 Thread(s)
Quoted: 4789 Post(s)
Liked 3,915 Times
in
2,546 Posts
Yes, BCD. Measure it and go search. Common BCDs are 74 (for triple inners), 110, 130, 139 (Shimano old school - I think I have this right, I've never had one), 144 (old school Campy). There is a conversion factor that lets you convert chainring bolt hole distance to BCD. Easy to find with a google search or found via geometry and trig or a CAD program.
Last edited by 79pmooney; 06-04-22 at 02:53 PM. Reason: Removed the words I wanted to highlight!
Likes For 79pmooney:
06-04-22, 03:26 PM
#6
Guest
Join Date: Sep 2020
Posts: 2,888
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 1346 Post(s)
Liked 3,270 Times
in
1,439 Posts
Yes. The BCD, as I mentioned in post #2.
If your chainring is worn, the chain and some of the rear cogs might also be worn. Drivetrain parts are often (but not always) replaced together.
Likes For Rolla:
06-04-22, 06:06 PM
#7
Senior Member
Join Date: Dec 2004
Posts: 1,077
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 542 Post(s)
Liked 622 Times
in
364 Posts
I didn't go into the weeds since I didn't know if you knew of the phenomena or not.
06-04-22, 10:42 PM
#8
Senior Member
Join Date: Nov 2018
Location: Redmond, WA & Bangkok, Thailand
Posts: 565
Bikes: 1999 Giant ATX MTB, 2002 Lemond Zurich, 2018 Fuji Transonic 2.3, 2019 Specialized Tarmac Disc Expert
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 170 Post(s)
Liked 391 Times
in
226 Posts
The triple on my Lemond Zurich is also 52/42/30 Ultegra with a 9sp cassette of 12-25 stock and later switched out to 12-28 when the original cassette wore out. That 30-28 low gear could climb up just about anything. Actually, if I have to use it I probably shouldn't be on something that steep anyway.
You should be able to find a 42 chain ring at most full service bike shops.
You should be able to find a 42 chain ring at most full service bike shops.
06-05-22, 01:05 AM
#9
Junior Member
Thread Starter
Whole crankset
While I almost exclusively use the middle ring on both my bikes with triples, the additional $ of getting a new, quality (Shimano, etc) CRANKSET is not unreasonable.
I’ll still hold onto the OEM, searching local shops for replacement 42. I may even opt for lowwear used piece that the shop might have in their spare parts drawers.
I’ll still hold onto the OEM, searching local shops for replacement 42. I may even opt for lowwear used piece that the shop might have in their spare parts drawers.
06-08-22, 02:59 PM
#10
Junior Member
Thread Starter
Middle chainring
These “codes” are stamped onto the chainring in question:
“52-42-V3”
“5009”
Is this some sort of standardized code?
“52-42-V3”
“5009”
Is this some sort of standardized code?
06-08-22, 08:27 PM
#12
Junior Member
Thread Starter
I ain’t greasin’ up meine hands … till it’s absolutely necessary, toots.
06-09-22, 01:44 AM
#13
The Wheezing Geezer
Join Date: Oct 2021
Location: Española, NM
Posts: 1,043
Bikes: 1976 Fredo Speciale, Jamis Citizen 1, Ellis-Briggs FAVORI, Rivendell Clem Smith Jr.
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 411 Post(s)
Liked 895 Times
in
440 Posts
You need not disassemble the crankset, just measure between two bolts, center to center, and look up the BCD.
06-13-22, 12:43 AM
#14
Junior Member
Thread Starter
