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  1. #1
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    Rennen Chainrings and Cogs



    Picked up a Rennen Chainring the other day instead of HBC. Very pleased with it so far.

    rennen design group :: 104BCD chainring

    Pros:

    Integrated chainring threads! (REALLY hate them)
    10 days from order to my door.
    Decimal gearing

    Neutral:
    3/16 thick before tapering to teeth (possible frame clearance issues if running over a 32T on some frames.)

    Cons:
    Costs slightly more than competitors.
    Last edited by Aaron1017; 01-26-2012 at 11:14 AM.

  2. #2
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    ...so enlighten me to the benefits of the decimal gearing. I've been looking at the Rennen cogs/chain rings as an alternative to HBC (I am impatient) and was wondering if I needed to consider a decimal ring or not...

    Also, whats the deal with the threaded chain ring bolt holes? What's the purported benefit?

  3. #3
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    Quote Originally Posted by trumpus View Post
    ...so enlighten me to the benefits of the decimal gearing. I've been looking at the Rennen cogs/chain rings as an alternative to HBC (I am impatient) and was wondering if I needed to consider a decimal ring or not...

    Also, whats the deal with the threaded chain ring bolt holes? What's the purported benefit?
    Decimal Gearing:
    rennen design group :: Decimal Gearing
    Click the link on the bottom left for a podcast.

    Benefit to threaded holes is very obvious if you've had to replace CRs before! No more dealing with chainring bolt wrench. Mine either come loose sometimes or are a ***** to remove.

  4. #4
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    Decimal gearing is more geared towards the BMX community, dialing in the gearing for racing depending on the track layout....

    Not that it would be a bad idea for SS...

    That being said I run a Rennen chaing ring and love it...


    Good quality stuff....
    Attached Thumbnails Attached Thumbnails Rennen Chainrings and Cogs-106_0367.jpg  

    Rennen Chainrings and Cogs-106_0369.jpg  

    Last edited by Yeti Clyde; 01-26-2012 at 12:39 PM.

  5. #5
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    Great Redline!!

  6. #6
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    Thanks...

  7. #7
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    My Rennen on my cruiser bike. Nice chainring. Ordered online, got it two weeks later to my door.
    Attached Thumbnails Attached Thumbnails Rennen Chainrings and Cogs-rennen.jpg  

    Last edited by mike5krnr; 01-27-2012 at 03:41 PM. Reason: Taking out an opinion

  8. #8
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    I recently ordered a chanring and cog from them. It took about 3 week to get the order. I am very happy so far. I love the integrated chainring bolts. It helps tremendously with keeping the chainring centered. I was in a constant battle with the Blackspire ring. The bolt holes were slightly bigger than the bolts. It didn't matter how tight I got the bolts the ring would never stay put.

  9. #9
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    Don't waste your money on decimal gearing. On a timed drivetrain, such as a chain or cogged belt, it's the number of teeth, not the Pitch Diameter, that determines your gear ratio.

    a 40/20 combo is always going to rotate the rear wheel 2x for every front revolution. Always.

    40.1/20 is the same as a 40/20. 1 crank rev = 2 wheel revs. Always always, always.

    Rennen is confusing friction drive technology (rubber/leather belts on smooth pulleys) with timed. Huge mistake on their part.

    If you want more friction and wear, the decimal gearing might be just the thing.
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  10. #10
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    Wow. Those Rennens are nice. Tall teeth, clean look. I have been running a Surly Stainless cog and chainring on my 26"; and before then a Salsa ring and before then a way awesome Rocket Ring which was cheap and good.

  11. #11
    Poacher
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    Captain America, thanks for wrecking my day!

    Just yesterday I finally decided to actually center my Blackspire 104 32 after two years. Now you tell me it won't stay put! Suckimoto! TMI TMI TMI

  12. #12
    Poacher
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    Yeti Clyde, Nice bike

  13. #13
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    I've found their aluminum cogs to be on the soft side and wear quickly. I won't buy again, and will stick with stainless steel from King or Surly so it lasts longer...

  14. #14
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    Quote Originally Posted by D.F.L. View Post
    Don't waste your money on decimal gearing. On a timed drivetrain, such as a chain or cogged belt, it's the number of teeth, not the Pitch Diameter, that determines your gear ratio.

    a 40/20 combo is always going to rotate the rear wheel 2x for every front revolution. Always.

    40.1/20 is the same as a 40/20. 1 crank rev = 2 wheel revs. Always always, always.

    Rennen is confusing friction drive technology (rubber/leather belts on smooth pulleys) with timed. Huge mistake on their part.

    If you want more friction and wear, the decimal gearing might be just the thing.

    More decimal gearing talk....


    Rennen Tech Talk in Pull - VintageBMX.com

  15. #15
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    Quote Originally Posted by AK47 View Post
    I've found their aluminum cogs to be on the soft side and wear quickly. I won't buy again, and will stick with stainless steel from King or Surly so it lasts longer...
    I would agree. They are extremely light, but not too strong.

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