Results 1 to 23 of 23
  1. #1
    mtbr member
    Reputation:
    Join Date
    Aug 2010
    Posts
    826

    Riot chainring clearance

    Mocking up my new Riot and wondering what acceptable clearance is for front chainring/chain stay?

    My caliper says about 5mm. Iím running Canfield cranks, Canfield/GXP BB with one spacer in drive side, and 30T SRAM Xsync spider/chainring which from what I can tell is 6mm standard offset.




    Sent from my iPhone using Tapatalk

  2. #2
    mtbr member
    Reputation:
    Join Date
    Mar 2015
    Posts
    69
    Quote Originally Posted by racefit View Post
    Mocking up my new Riot and wondering what acceptable clearance is for front chainring/chain stay?

    My caliper says about 5mm. Iím running Canfield cranks, Canfield/GXP BB with one spacer in drive side, and 30T SRAM Xsync spider/chainring which from what I can tell is 6mm standard offset.




    Sent from my iPhone using Tapatalk
    Itís going to sound counter intuitive, but you need to get rid of that drive side spacer to properly install cranks with a gxp bottom bracket. I destroyed two bottom brackets before learning this lesson; that spacer isnít actually moving the chainring out from your chainstay.

  3. #3
    mtbr member
    Reputation:
    Join Date
    Aug 2010
    Posts
    826

    Riot chainring clearance

    Quote Originally Posted by mothertruckinsteve View Post
    Itís going to sound counter intuitive, but you need to get rid of that drive side spacer to properly install cranks with a gxp bottom bracket. I destroyed two bottom brackets before learning this lesson; that spacer isnít actually moving the chainring out from your chainstay.
    Iím not the expert on GXP BBís, but Iíve run SRAM cranks and GXP BBís on my bikes for the last 5 years. All had 1 driveside spacer and theyíve all been flawless. IIRC SRAM shows spacers as an option for install.

    As far as moving the chainring out I canít see how it wouldnít. It would just shorten the available spindle interface on the NDS no?

    EDIT: Here are the install instructions from Canfield for their crank and BB. It seems you donít NEED spacers, but itís allowable as an option. It also seems you can decrease chainring clearance by adding a spacer to the NDS. If this is true you would shorten the available spindle space on the NDS by the same amount as doing it on the DS, no? Am I missing something?


  4. #4
    mtbr member
    Reputation:
    Join Date
    Mar 2015
    Posts
    69
    Quote Originally Posted by racefit View Post
    Iím not the expert on GXP BBís, but Iíve run SRAM cranks and GXP BBís on my bikes for the last 5 years. All had 1 driveside spacer and theyíve all been flawless. IIRC SRAM shows spacers as an option for install.

    As far as moving the chainring out I canít see how it wouldnít. It would just shorten the available spindle interface on the NDS no?


    Sent from my iPhone using Tapatalk
    Iím not an expert on them either, but my understanding is they there is some float on the bearings and those spacers adjust that as opposed to the position of the chainring, it may be appropriate or needed on some frames but the Riot is not one of them.

    In my experience running Canfield cranks on a riot that spacer will cause one of two things to happen. Either the left crank arm will loosen and fall off in the middle of your ride, or it will tighten and annihilate the bottom bracket cups and seals. Neither of which are much fun to deal with

  5. #5
    mtbr member
    Reputation:
    Join Date
    Aug 2010
    Posts
    826
    Quote Originally Posted by mothertruckinsteve View Post
    Iím not an expert on them either, but my understanding is they there is some float on the bearings and those spacers adjust that as opposed to the position of the chainring, it may be appropriate or needed on some frames but the Riot is not one of them.

    In my experience running Canfield cranks on a riot that spacer will cause one of two things to happen. Either the left crank arm will loosen and fall off in the middle of your ride, or it will tighten and annihilate the bottom bracket cups and seals. Neither of which are much fun to deal with
    Two of the most respected LBSís locally actually recommended using a DS spacer on previous builds. One saying he always uses one.

    Not trying to prove my point, just expressing my experiences and understand my options.

    If I did decide to go without a spacer, my chainring would be that much closer,2.5mm with my caliper. Things would be getting tight at that point and it makes me think I should go with a 3mm chainring to gain back some clearance. Having said that, Iíve had some VERY tight clearances on some Nimbles 9s and never had a problem.


    Sent from my iPhone using Tapatalk

  6. #6
    mtbr member
    Reputation:
    Join Date
    Mar 2015
    Posts
    69
    Iím just trying to save you troubles that I went through when building up the same frame with the same cranks. The Bros also weighed in on this topic in the main forum thread about the Riot and said their cranks should be run without spacers on the Riot. You can call/email them to confirm.

    After multiple frustrating rides with crank arms falling off and bottom bracket cups destroyed I removed said spacer from the equation and those cranks have worked flawlessly on my Riot for 2 years, using a direct mount 6mm offset 30 tooth Absolute Black chainring. Clearances look tight, but have never been an issue.

  7. #7
    mtbr member
    Reputation:
    Join Date
    Aug 2010
    Posts
    826
    Quote Originally Posted by mothertruckinsteve View Post
    Iím just trying to save you troubles that I went through when building up the same frame with the same cranks. The Bros also weighed in on this topic in the main forum thread about the Riot and said their cranks should be run without spacers on the Riot. You can call/email them to confirm.

    After multiple frustrating rides with crank arms falling off and bottom bracket cups destroyed I removed said spacer from the equation and those cranks have worked flawlessly on my Riot for 2 years, using a direct mount 6mm offset 30 tooth Absolute Black chainring. Clearances look tight, but have never been an issue.
    I appreciate the feedback, glad I asked before going forward.

    Here what it looks like without the spacer installed. I canít even get the calipers inside to measure, but Iíd estimate about 1.5mm clearance.








    Sent from my iPhone using Tapatalk

  8. #8
    mtbr member
    Reputation:
    Join Date
    Mar 2015
    Posts
    69
    No problem, and agree that it looks really tight, but itís always looked uncomfortably tight on every Canfield Iíve owned (4), and Iíve never had issues. Iíd put calipers on mine or take pictures but Iím away from my bike for another week. If youíre unsure email some pics of your setup to Canfield, theyíll make sure youíve got the best setup info available.

    For reference, with these cranks, when tightening the bolt on the nondriveside crank arm it should tighten until you feel a hard bottom out. If you werenít getting that feeling with the spacer (I never did) then they werenít installed correctly.

  9. #9
    mtbr member
    Reputation:
    Join Date
    Aug 2010
    Posts
    826
    Quote Originally Posted by mothertruckinsteve View Post
    No problem, and agree that it looks really tight, but itís always looked uncomfortably tight on every Canfield Iíve owned (4), and Iíve never had issues. Iíd put calipers on mine or take pictures but Iím away from my bike for another week. If youíre unsure email some pics of your setup to Canfield, theyíll make sure youíve got the best setup info available.

    For reference, with these cranks, when tightening the bolt on the nondriveside crank arm it should tighten until you feel a hard bottom out. If you werenít getting that feeling with the spacer (I never did) then they werenít installed correctly.
    Agreed on tight clearances in Canfields. One of my N9s I couldnít even see a space with the naked eye. Chainring never touched to stays though.

    My last pics are without torquing down. Not sure how much more inward it will move after torquing but with this clearance it makes me nervous, especially with a FS rear triangle, as I would imagine there is more chance of lateral movement when the suspension goes through its movement as it ages and linkage breaks in.

    We haveít even talked about chainline yet...


    Sent from my iPhone using Tapatalk

  10. #10
    mtbr member
    Reputation:
    Join Date
    Oct 2015
    Posts
    1,280
    Quote Originally Posted by racefit View Post
    I appreciate the feedback, glad I asked before going forward.

    Here what it looks like without the spacer installed. I canít even get the calipers inside to measure, but Iíd estimate about 1.5mm clearance.








    Sent from my iPhone using Tapatalk
    Judging by your pick, I run mine that close or even a little closer. No issues. I did check my pivots during (3◊ a ride) the first few rides. And weekly there after.

  11. #11
    mtbr member
    Reputation:
    Join Date
    Aug 2010
    Posts
    826
    Just torqued the B.B. cups and it moved close enough that the chain rubs the stay. Clears without the chain but ainít gonna work with it on.

    Now I either get a 3mm chainring or use a spacer.


    Sent from my iPhone using Tapatalk

  12. #12
    mtbr member
    Reputation:
    Join Date
    Aug 2010
    Posts
    826
    Just checked out Canfield chainrings on their site and theyíre listed as -3mm offset.


    Sent from my iPhone using Tapatalk

  13. #13
    mtbr member
    Reputation: OwenM's Avatar
    Join Date
    Oct 2012
    Posts
    1,179
    No drive side spacer with a GXP and 73mm BB. Everything is spaced and held together on the NDS. Using a DS spacer can only increase your chainring clearance if it is forcing the crankarm out by pushing the bearing cover on the drive side against it, and in doing so keeping the NDS of the spindle from seating in the crankarm properly. That's why the talk of trashed bearings(I suppose from crushing the cover into the bearings when torquing the NDS bolt down and causing it to bind?) and cranks falling off.
    Canfield does sell 3mm offset chainrings, but my ovals are the standard 6mm. They are close, like in your pics, but haven't been a problem. So close that when I built my Riot, I lubed the chain heavily, forgot to wipe it down in my excitement to ride the bike, and had sludge wiping off on the chainstay. First thought: "Holy crap, chainring's rubbing!" But it wasn't...
    Notice there is no "tip" on those instructions for moving the chainring *further* from the frame, only closer to it.

  14. #14
    mtbr member
    Reputation:
    Join Date
    Aug 2010
    Posts
    826
    Quote Originally Posted by OwenM View Post
    Notice there is no "tip" on those instructions for moving the chainring *further* from the frame, only closer to it.
    I did notice that and thought it was odd since my experience with Canfield frames has always been about getting the chainring further away.

    Is there something different about the Canfield cranks vs. the SRAM design?




    Sent from my iPhone using Tapatalk

  15. #15
    Nouveau Retrogrouch SuperModerator
    Reputation: shiggy's Avatar
    Join Date
    Dec 1998
    Posts
    48,236
    Quote Originally Posted by racefit View Post
    Iím not the expert on GXP BBís, but Iíve run SRAM cranks and GXP BBís on my bikes for the last 5 years. All had 1 driveside spacer and theyíve all been flawless. IIRC SRAM shows spacers as an option for install.

    As far as moving the chainring out I canít see how it wouldnít. It would just shorten the available spindle interface on the NDS no?

    EDIT: Here are the install instructions from Canfield for their crank and BB. It seems you donít NEED spacers, but itís allowable as an option. It also seems you can decrease chainring clearance by adding a spacer to the NDS. If this is true you would shorten the available spindle space on the NDS by the same amount as doing it on the DS, no? Am I missing something?

    You are not understanding how the GXP BB/crank works.
    The scrank spindle captures the NDS bearing to laterally fix the crank. The spindle is free floating in the DS bearing.

    By the Canfield instructions ( http://canfieldbrothers.com/wp-conte...k-Assembly.pdf ), a 1mm spacer between the spindle and NDS bearing may be used to move the chainline outboard.
    A spacer under the NDS cup is used to move the chainline inboard.

    Spacers under the DS cup do nothing to change the chainline.

    No fundamental difference between the SRAM and Canfield designs.

  16. #16
    moar alike..
    Reputation: Deerhill's Avatar
    Join Date
    Dec 2009
    Posts
    4,969
    Make sure you have the steel fixing bolt (w/o the washer) if you put in the nds internal extender/spacer, some Truvativ/Sram one's are aluminum and the threads strip right off the bolt.
    All barks have been rendered into english...

  17. #17
    mtbr member
    Reputation:
    Join Date
    Aug 2010
    Posts
    826
    Spoke to Canfield last night and they do not recommend a DS spacer.

    Now I need a 0mm chainring.


    Sent from my iPhone using Tapatalk

  18. #18
    mtbr member
    Reputation: OwenM's Avatar
    Join Date
    Oct 2012
    Posts
    1,179
    I wouldn't. It'll give you more chainring clearance(which you don't need, IMO), but make your chainline worse.
    If you're just gonna do it anyway, hit me up via PM. I've got a 0 offset direct mount AB oval 32T that was briefly used on a SS setup with my Yelli Screamy and could use some purpose in life...

  19. #19
    mtbr member
    Reputation:
    Join Date
    Aug 2010
    Posts
    826
    Quote Originally Posted by OwenM View Post
    I wouldn't. It'll give you more chainring clearance(which you don't need, IMO), but make your chainline worse.
    If you're just gonna do it anyway, hit me up via PM. I've got a 0 offset direct mount AB oval 32T that was briefly used on a SS setup with my Yelli Screamy and could use some purpose in life...
    After speaking to Sean at Canfield, he recommended I get a 0mm or -3mm chainring.


    Sent from my iPhone using Tapatalk

  20. #20
    mtbr member
    Reputation: J.B. Weld's Avatar
    Join Date
    Aug 2012
    Posts
    9,468
    Quote Originally Posted by racefit View Post
    Just torqued the B.B. cups and it moved close enough that the chain rubs the stay. Clears without the chain but ainít gonna work with it on.

    Now I either get a 3mm chainring or use a spacer.


    Sent from my iPhone using Tapatalk

    I'm not quite understanding how the chainring clears but the chain doesn't, the last pic on post #10 shows the chain wrapping around the ring but obviously it doesn't run that way. Maybe I'm missing something but from what I see the clearance is ok, how is the chainline?

    Shiggy (is back!) of course is right, the ND side cup is what controls the chainline.
    I brake for stinkbugs

  21. #21
    mtbr member
    Reputation: cpolism's Avatar
    Join Date
    Mar 2010
    Posts
    203
    Iíve got the Hope crankset with the spiderless narrow/wide ring which I believe is a 3mm offset. It is extremely close as well, and there are wear marks on the stays. Iím glad I saw this, because I was about to purchase the new RF Next R cranks with the absolute black oval ring thatís 6mm. Now this has me second guessing. On a Ď16 Riot for what itís worth...

  22. #22
    mtbr member
    Reputation:
    Join Date
    Apr 2004
    Posts
    15
    I had issues with my 175 RF Next cranks rubbing the back chainstay. You can forget about using the rubber boot and they absolutely needed a DS spacer. I switched to 170 SixC and the issue is relieved. I can't scientifically say if it was the stiffer crank or the -5mm length that mitigated the issue, but I would definitely not recommend 175 RF Next.

    I am running a 32t AB oval btw, there is very little clearance but no metal on metal rubbing. The oval does illicit a bit more movement due to the constantly changing AS values. So, I get smoother pedaling circles, but more suspension bob. For me, at least it is worth the trade.

  23. #23
    mtbr member
    Reputation:
    Join Date
    Oct 2015
    Posts
    1,280
    You can get some 1mm spacers on Amazon really cheap. I find they are essential to getting as close as possible to the chainstays fo keep a better chain line.

Similar Threads

  1. Oh, that Yelli chainring clearance...again...
    By canyonrat in forum Canfield
    Replies: 5
    Last Post: 12-01-2011, 07:03 PM
  2. WFO chainring clearance?
    By JanBoothius in forum Niner Bikes
    Replies: 4
    Last Post: 05-21-2011, 08:49 PM
  3. XO 2x10 for Tallboy, 42 chainring clearance?
    By Lenz43 in forum 29er Bikes
    Replies: 0
    Last Post: 04-22-2011, 06:24 AM
  4. Scale 29er Elite Chainring Clearance
    By BobShort in forum Scott Sports
    Replies: 2
    Last Post: 04-06-2011, 02:49 PM
  5. Chainring clearance?
    By bikerboyj17 in forum Drivetrain - shifters, derailleurs, cranks
    Replies: 0
    Last Post: 02-07-2011, 04:59 PM

Members who have read this thread: 46

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

THE SITE

ABOUT MTBR

VISIT US AT

mtbr.com and the ConsumerReview Network are business units of Invenda Corporation

(C) Copyright 1996-2018. All Rights Reserved.