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  1. #1
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    Single front ring query.

    Hello tech wizards;

    I recently switched the rear wheel on my Proflex 855 to a 24. I'm finding the riding style that I use it for {basically a coffeeshop cruiser} that the granny ring and the big ring are not getting any use.

    I've already locked out the front derailler from going into the granny. {The chain rubbed on the rear Hookworm pretty badly in the granny.}

    Ideally, I'd like to remove both the big and granny rings and rock with the middle 34t ring. {To remove some weight on this already heavy 34 lb'er!}
    It's a 94mm BCD Sugino Impel 500 crankset with the hidden 5th crankbolt crankarm design, if that helps.

    What do you techies think is the best way to go on this?
    G

  2. #2
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    Take the granny off, swap the big ring for a light bashguard and lock down the front derailleur (you can remove the cabling and shifter). That's the basic method.

    For a slicker take, replace the middle ring with a DH or Singlespeed ring and replace the front derailleur with an N-Guard or similar chainguide on the inside.

    You aren't going to save much weight on the crank itself (granny's are light due to size and bashguards tend to be about the same weight as a big ring) but there's 1/2-1 pound you can easily lose by stripping off the shifty bits.

  3. #3
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    Quote Originally Posted by thecrazyfinn
    Take the granny off, swap the big ring for a light bashguard and lock down the front derailleur (you can remove the cabling and shifter). That's the basic method.
    If I do it this way, couldn't I just remove both the granny, big ring and do without a bashguard?

    Quote Originally Posted by thecrazyfinn
    For a slicker take, replace the middle ring with a DH or Singlespeed ring and replace the front derailleur with an N-Guard or similar chainguide on the inside.
    As above; The locked front derailler is in affect, acting as a chainguide, isn't it? Going with the cheap and cheerful basic method would suffice for light trail riding I presume.

    Quote Originally Posted by thecrazyfinn
    You aren't going to save much weight on the crank itself (granny's are light due to size and bashguards tend to be about the same weight as a big ring) but there's 1/2-1 pound you can easily lose by stripping off the shifty bits.
    In regard to "bashguards." Is there any manufacturers that make one that replaces the big ring for a hidden 5th crankbolt design one? 94mm BCD?

    Thanks for the response, Crazyfinn!
    G.

  4. #4
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    Quote Originally Posted by GinSonic
    If I do it this way, couldn't I just remove both the granny, big ring and do without a bashguard?
    Yes, but you'll need a new set of chainring bolts

    As above; The locked front derailler is in affect, acting as a chainguide, isn't it? Going with the cheap and cheerful basic method would suffice for light trail riding I presume.
    Yep, it's a chainguide in this setup, and will handle just about anything short of downhill just fine.

    In regard to "bashguards." Is there any manufacturers that make one that replaces the big ring for a hidden 5th crankbolt design one? 94mm BCD?

    Thanks for the response, Crazyfinn!
    G.
    Plenty of options for 94BCD Chainguards. I'd probably go with the RaceFace one myself, although it's one of the pricier ones. You'd want to go with a lighter chainguard rather than a hefty bashguard if you've got a hidden bolt crank, it's already hard enough to get rings on and off of those.

  5. #5
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    Quote Originally Posted by thecrazyfinn
    Yes, but you'll need a new set of chainring bolts
    Yes. I was aware of the required shorter chainring bolts. I guess they're attainable at any LBS, huh?



    Quote Originally Posted by thecrazyfinn
    Yep, it's a chainguide in this setup, and will handle just about anything short of downhill just fine.
    Thanks for the confirmation.



    Quote Originally Posted by thecrazyfinn
    Plenty of options for 94BCD Chainguards. I'd probably go with the RaceFace one myself, although it's one of the pricier ones. You'd want to go with a lighter chainguard rather than a hefty bashguard if you've got a hidden bolt crank, it's already hard enough to get rings on and off of those.
    Yes. I do see many options for 94BCD chainguard/bashrings. However, most of the ones I've seen, including your suggested RaceFace ones, have a cutout area between two crankbolts.

    Many of them look to be for five spider cranks with the arm positioned between two crankbolts as opposed to the hidden fifth design on the Sugino on my bike.

    I've seen a few chainguard/bashrings that appear to adhere to the requirements of the crank design of my cranks, but they don't say if they're meant to mount on the outside of the big ring, or are meant to replace the big ring.

    Assuming this has a 94BCD, would something like this work for my requirements?




    Do you or anyone else have any suggestions for the latter? In keeping with my requirements, of course.
    G.

  6. #6
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    Anyone????
    G.

  7. #7
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    file off the teeth on your big ring and you now have a bash gaurd. remove the granny and frt derailure.

  8. #8
    beerowulf
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    Quote Originally Posted by GinSonic
    Yes. I was aware of the required shorter chainring bolts. I guess they're attainable at any LBS, huh? G.
    I think the cheap and cheerful method to dispense with the bashie is to find a trashed chainring (bigger the better for grinder clearance) and use a grinder, hacksaw or dremel tool to grind/ cut off the bolt centres. Use the four or five as spacers and mount your middle ring as normal with the stock chainring bolts...

    The LBS offered me a set of 5 new shorties, but the tab was going to be $15, the cheap and cheerful grinder route costs some time and the satisfaction of building up the bar bike w/o any outlay of cash....hehe.

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