Results 1 to 4 of 4
  1. #1
    mtbr member
    Reputation:
    Join Date
    Feb 2009
    Posts
    226

    2x10 crankset & helius CC

    Due to the excellent offer that Merlin have on the 2012 XT groupset, I have a question.

    Will the suspension action of my Helius CC be screwed up by fitting a 28/40 crankset as opposed to a 22/32 that I currently have on there.

    I know it affects single pivot bikes, but does it have any affect on the design of the Nicolai

  2. #2
    mtbr member
    Reputation:
    Join Date
    Jul 2006
    Posts
    898
    I don't know specifically, but the effect your talking about is determined by where the pivot point is in relation to the front chain ring (and thus the line of tourque of the chain).

    On a single pivot bike it's much easier to see if chain torque will be a problem because the pivot is a) static and b) is clearly visible, i.e. the pivot is physically located on the bike. If the chain line is in line with the pivot then the feel will be neutral and active. If the chainline is above the pivot, then I think the suspension will want to compress and if it's below then it will want to extend.

    Every other design that is not a single pivot is just some variant of a virtual pivot, i.e. the point around which the rear wheel is rotating is not physically located on the bike, but at some virtual point. That still means that there is one, actual point around which the wheel pivots, so in effect, at any given point in the travel, your Helius is still acting like a single pivot bike.

    You can always find that specific point by drawing two lines that pass through the upper two and the lower two pivots; on the Helius CC, the lower line would pass through the chainstay and the BB pivot and the upper line would pass through the two pivots located on the top swing link (i.e. the one attached to the top tube and the one attached to the damper unit itself).

    Obviously this means that the pivot point is moving when the bike is cycled through its travel, in the case of the Helius, that path is downwards and forwards.

    If you can picture roughly where that point is, you should be able to see what the general effect will be of running the gear combo you're talking about.

  3. #3
    mtbr member
    Reputation:
    Join Date
    Dec 2010
    Posts
    15
    very nice!!!!!!

  4. #4
    mtbr member
    Reputation: Midgetman's Avatar
    Join Date
    Feb 2011
    Posts
    203
    Actually I'm riding a 26/38 crankset on my Nonius single-pivot bike and nothing is messed up. The only thing that had a negative impact on the rear suspension so far was the Rohloff hub...

Similar Threads

  1. 2x10 180mm crankset?
    By GTscoob in forum Drivetrain - shifters, derailleurs, cranks
    Replies: 5
    Last Post: 06-01-2011, 12:22 AM
  2. E13 XCX/MRP 1X w/ 2X10 Crankset
    By lucero in forum Drivetrain - shifters, derailleurs, cranks
    Replies: 0
    Last Post: 04-30-2011, 12:59 PM
  3. Which 2x10 crankset on Blur xc carbon?
    By Hasse in forum Santa Cruz
    Replies: 13
    Last Post: 04-21-2011, 12:22 PM
  4. Which 2x10 Crankset??
    By JTeezy in forum Drivetrain - shifters, derailleurs, cranks
    Replies: 1
    Last Post: 01-10-2011, 08:10 AM
  5. who makes a 22/32T 2x10 carbon crankset?
    By tmilam in forum Drivetrain - shifters, derailleurs, cranks
    Replies: 5
    Last Post: 12-02-2010, 11:13 AM

Posting Permissions

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