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  1. #26
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    I want to see some pictures of your shop.

  2. #27
    Wēk Ss
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    You'd need some different chainring bolts, but you can't guarantee compatibility across the board and you'd need to do some operating on the crank arm.

    Andersen Machine makes a 30T 104BCD right now as well, with supplied bushings and bolts.

  3. #28
    PRETENDURO
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    That is some beautiful handiwork!
    QUOTE from MTBR.COM: You have given Brewtality too much Reputation in the last 24 hours, try again later.

  4. #29
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    Regarding a 30T 104BCD ring, how much would you have to "square out" the chain pitch circle to get the bolt holes to clear standard placement? Would you even notice the deviation? Just a thought.

  5. #30
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    Quote Originally Posted by IAmHolland View Post
    Andersen Machine makes a 30T 104BCD right now as well, with supplied bushings and bolts.
    Cheaters! Actually, that's brilliant.

  6. #31
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    Quote Originally Posted by shinewheel View Post
    Regarding a 30T 104BCD ring, how much would you have to "square out" the chain pitch circle to get the bolt holes to clear standard placement? Would you even notice the deviation? Just a thought.
    Looks like the solution that a couple companies have come up with is to thread the chainring.

  7. #32
    ballbuster
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    and...

    Quote Originally Posted by icantdrive65 View Post
    I just did a quick drawing of a 30T 104 BCD chainring and found the fundamental problem with it. The profile of the teeth cuts into the chainring bolts.
    The chain plates ride on top of the crank spider. There is a guy making 30t middle rings for 4 arm cramks, and he uses bolts that goes through the big ring and threads directly into the middle chainring itself to eliminate that one bolt. You have to file a bevel on the spider so the chain plates clear.

  8. #33
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    Quote Originally Posted by pimpbot View Post
    The chain plates ride on top of the crank spider. There is a guy making 30t middle rings for 4 arm cramks, and he uses bolts that goes through the big ring and threads directly into the middle chainring itself to eliminate that one bolt. You have to file a bevel on the spider so the chain plates clear.
    I saw that on a couple different rings. I'm a little surprised that people are willing to file their crank arms down. I guess it makes more sense for the 1x9 or 1x10 setups when you want a slightly lower gear than you can achieve with the biggest cog available on a cassette.

    On a singlespeed setup, it would make more sense to increase the size of the rear cog. Is it a preference for a specific ratio that can't be duplicated exactly by increasing rear cog size? Maybe I should take that question back to the SS forum.

  9. #34
    Clyde on a mission!
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    Quote Originally Posted by icantdrive65 View Post
    A spiderless ring at that price should be no problem if I can sell them without a middleman. I don't want to get stuck in a spot like HBC, so I'm weighing what options I could make available to keep rings in stock and not have customers waiting months until they show up with pitchforks and torches in hand.
    That could be dealt with simply by holding out asking for payment until the item is ready to be shipped. If you're backed up for a long time and some customers decide to cancel, you build a small stock to sell directly.

    Thumbs up on the work, it looks awesome, however I'm not sure I would be comfortable putting my ankle near that chainsaw chainguard, looks like it can make quite a mess of your leg in a crash.

  10. #35
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    Quote Originally Posted by Sandrenseren View Post
    That could be dealt with simply by holding out asking for payment until the item is ready to be shipped. If you're backed up for a long time and some customers decide to cancel, you build a small stock to sell directly.
    It's amazing how often people can change their mind after ordering something. The thing is, communication saves lots of headaches. I'm sure I can get the different bolt patterns and spline types dialed in and make a fairly quick transition from order time to machining and shipping. The trick is to get it shipped before the customer changes their mind.

    Thumbs up on the work, it looks awesome, however I'm not sure I would be comfortable putting my ankle near that chainsaw chainguard, looks like it can make quite a mess of your leg in a crash.
    Thanks. I have been running the previous chainguard for 10 years and it has never bitten me yet. It's not as sharp as it looks. Just sharp enough to bite into a log.

  11. #36
    ballbuster
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    I did mine

    Quote Originally Posted by icantdrive65 View Post
    I saw that on a couple different rings. I'm a little surprised that people are willing to file their crank arms down. I guess it makes more sense for the 1x9 or 1x10 setups when you want a slightly lower gear than you can achieve with the biggest cog available on a cassette.

    On a singlespeed setup, it would make more sense to increase the size of the rear cog. Is it a preference for a specific ratio that can't be duplicated exactly by increasing rear cog size? Maybe I should take that question back to the SS forum.
    I ran an Action Tec 20t granny gear on my XT cranks for a while, on the 29er. That extra low gear was a lifesaver. The filing is pretty easy. It only took me like 20 minutes to do a nice neat job. I just took a super sharp fine hacksaw, and cut about 1 or 2mm down from the edge of the threaded spider part on the outside, guiding the blade with my finger. I cut around and made an arc like the big circle around where the chain will ride. I finished it up with a few strokes of a fine file.

    I have since scored some 180mm M952 XTR cranks with a 58/94mm 5 arm spider. 20t and 30t naturally fit with no mods. The nice thing is, the jump from 20t to 30t up front is only 3 cogs in back. I didn't like the jump from 20t to 32t. I found myself dropping back to granny gear a lot. Not so much with the 30t middle.

    20/30/42 is perfect for 29ers, IMO.
    Last edited by pimpbot; 12-01-2012 at 07:03 PM.

  12. #37
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    I got a few pieces anodized. Here is a finished bash guard.

  13. #38
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    That looks so clean!
    Badass man

  14. #39
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    Still playing around with engraving.

  15. #40
    OOOOOOOh Gee Are Eee
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    Quote Originally Posted by icantdrive65 View Post
    I saw that on a couple different rings. I'm a little surprised that people are willing to file their crank arms down. I guess it makes more sense for the 1x9 or 1x10 setups when you want a slightly lower gear than you can achieve with the biggest cog available on a cassette.

    On a singlespeed setup, it would make more sense to increase the size of the rear cog. Is it a preference for a specific ratio that can't be duplicated exactly by increasing rear cog size? Maybe I should take that question back to the SS forum.
    I agree, I'd love to have a 30t front ring for my 1x9 29ers. For SSers, smaller rings, shorter chains, a tiny but more clearance.. is appealing, mostly aesthetics, but a small amount of weight loss too.

  16. #41
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    Quote Originally Posted by Ogre View Post
    I agree, I'd love to have a 30t front ring for my 1x9 29ers. For SSers, smaller rings, shorter chains, a tiny but more clearance.. is appealing, mostly aesthetics, but a small amount of weight loss too.
    The flip side, for me at least, is the SS sprockets wear SO fast. With less teefs, the wear is even faster.

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