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  1. #1
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    Idea! Paging Dusty Bottoms, Jaybo, Jayem, or Tscheezy

    Guys, I have a new puzzle for you that is driving me crazy. Just put on a new (replacement) XTR cassette (11-34), new Wipperman 908 chain, and new 22 and 32 tooth chain rings to replace worn-out parts on the Spot (actually they migrated from the old bike to the new Turner this Spring).

    Previously, I could back pedal for obstacle clearance while in my 22 - 34 or the 32 - 34 without a hang up. With the new parts, it shifts down within one back revolution and hangs. Changed out the derailleur hanger, have checked the rear derailleur (XTR 952 - new this Spring) for upper limit, cable tension, bent cage, etc.; no joy.

    Put the old parts back on and presto - I can backpedal until tomorrow. Even tried trading out for another new cassette to see if that was it - same thing.

    Because I am using a FSA Mega Exo crank, with the spacer on the non-drive side, my chain line is not great up in 34 land and I am starting to think that the new cassette has nice crisp sharp edges on the teeth and once it wears in, I will be able to backpedal, but I am not convinced because I am also not a great bike wrench.

    As I read this forum, your thoughts are always insightful and welcome. For example, thanks for the zerk, tip, Tscheezy; it is holding great with JB Weld.

  2. #2
    No, that's not phonetic
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    First, NEVER list me in the same sentence with those guys.

    Second, a new chain will have less lateral play than an old chain, and will not feed around corners (out of a straight chainline onto an angled cassette cog) as well as the old one and would probably contribute to dropping while backpedaling. The fewest spacers under the drive side bb cup will give you the narrowest chainline spacing, which is a good thing in your case. The adjustment of the rear der should not play any role in this. I have had the best luck with Sram chains. The one time I bought a Wippermann I had some pretty bad chainsuck and never went back to them (probably the fault of XTR rings wearing quickly and the chain wearing slowly- both started new). Too bad, because I really like the idea of stainless steel in a chain.
    My video techniques can be found in this thread.

  3. #3
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    OK, I will omit any mention of those other guys named Dusty Bottoms, Jaybo and Jayem

    I hear you on that concept of lateral play - maybe I am a better wrench than I think.

    In re: Wipperman's, been using them for 5 years and Rohloff's before that (when you could get them) and no problems whatsoever. They last twice as long as everything else, never rust, and seem to have an equivalent lifespan as that of the cassette.

    Thanks.

  4. #4
    Elitest thrill junkie
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    Sometimes excessive pressure from a QR causes the hub to bind a bit, and prevents the backpedaling thing from working well. Every once and a while the cassette contacts the dropout a little on the bike as well, creating friction and causing the same problem.

    Cheezy's explaination sounds logical.

    Also check the pulleys on the derailer.
    "It's only when you stand over it, you know, when you physically stand over the bike, that then you say 'hey, I don't have much stand over height', you know"-T. Ellsworth

    You're turning black metallic.

  5. #5
    No, that's not phonetic
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    Quote Originally Posted by steve47co1
    OK, I will omit any mention of those other guys named Dusty Bottoms, Jaybo and Jayem
    Thanks. I am already getting heckled in my inbox.
    My video techniques can be found in this thread.

  6. #6
    Daniel the Dog
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    I can understand that...

    Quote Originally Posted by tscheezy
    First, NEVER list me in the same sentence with those guys.

    Second, a new chain will have less lateral play than an old chain, and will not feed around corners (out of a straight chainline onto an angled cassette cog) as well as the old one and would probably contribute to dropping while backpedaling. The fewest spacers under the drive side bb cup will give you the narrowest chainline spacing, which is a good thing in your case. The adjustment of the rear der should not play any role in this. I have had the best luck with Sram chains. The one time I bought a Wippermann I had some pretty bad chainsuck and never went back to them (probably the fault of XTR rings wearing quickly and the chain wearing slowly- both started new). Too bad, because I really like the idea of stainless steel in a chain.
    Very funny! Particularly since I'm not mechanical whiz. Wrong guy here

    One time in a galaxy time long ago I had a rear hub that was sticky as mud due to some worn out bearings. It was causing some chain suck and would not backpedal well without causing problems with the chain. I rebuilt it and my chain suck went away. All I got! Good luck....

    Jaybo

  7. #7
    Natl. Champ DH Poser/Hack
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    Quote Originally Posted by steve47co1
    As I read this forum, your thoughts are always insightful and welcome. For example, thanks for the zerk, tip, Tscheezy; it is holding great with JB Weld
    a bonding agent to hold a loose zerk in? what a great idea! why didnt i think of that? cheesey gets all the love around here but thats cool. hes the #1 go to guy in here afterall and has bailed every last one of us outta a jam. many more than once, myself included. ill just be over here nursin my bruised ego. hehe.
    No, I'm NOT back!

  8. #8
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    chainline

    I think tscheezy (and steve) called this one with the new parts not wanting to be loose enough or broken in enough to allow you to backpedal. Chain not flexing, gear edges too sharp...

    This problem could really point to another problem, like chainline.....You said your chainline wasn't that good. What is your chainline?

    If it still has the problem after a few good rides you should try shifting your chainline toward the center of the bike.

  9. #9
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    Your old cassette may have fitted up to your freehub a little deeper(over time), so the new cassette might not be spaced exactly the same. See if the new one has any play.

    I think it might be the pulleys on your derailleur. Those pulleys are pretty soft and get worn easily. You've got a new cassette and new chain with tight tolerances, and old pulleys with wider spaced teeth due to a stretched out old chain. Chain doesn't fit into pulley teeth while backpedaling....creates slack....chain falls off cogs.

    rule #1 - mixing old and new drivetrain parts never seems to work perfectly.

    rule #2 - get the hell out of the 34 cog!!!!

  10. #10
    Roy
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    Quote Originally Posted by steve47co1
    Put the old parts back on and presto - I can backpedal until tomorrow. Even tried trading out for another new cassette to see if that was it - same thing.
    Swap in the new parts one at a time until you can't backpedal anymore.

    I've also had bad experience with Wipperman chains.

  11. #11
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    Good job! Dusty Bottoms wins the prize

    Well, I finally found the solution to my problem - the top pulley on the rear derailleur had too much lateral play in it and as soon as I traded it out for a newer one, presto - the bike backpedals fine.

    Now I am wondering if my bad chainline was the cause of the deterioration of the top pulley? Time will tell.

    For glader60, I have no options to improve my chainline save a new crankset with a true BB and spindle - thses new outboard bearing BB's (FSA Mega Exoonly have limited lateral adjustment - a spacer on the drive side or the other is the only adjustment.

    For Dusty Bottoms - yes I would like to get out of my 34t cog but here in CO, we start our rides at 7,000 and everything goes up from there. A 34/32 combo is the gearing of choice here for traction and control.

    Also, for Dusty, everything was new save the rear derailleur, including a new hanger.

  12. #12
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    Quote Originally Posted by steve47co1
    Well, I finally found the solution to my problem - the top pulley on the rear derailleur had too much lateral play in it and as soon as I traded it out for a newer one, presto - the bike backpedals fine.

    Now I am wondering if my bad chainline was the cause of the deterioration of the top pulley? Time will tell.

    For glader60, I have no options to improve my chainline save a new crankset with a true BB and spindle - thses new outboard bearing BB's (FSA Mega Exoonly have limited lateral adjustment - a spacer on the drive side or the other is the only adjustment.

    For Dusty Bottoms - yes I would like to get out of my 34t cog but here in CO, we start our rides at 7,000 and everything goes up from there. A 34/32 combo is the gearing of choice here for traction and control.

    Also, for Dusty, everything was new save the rear derailleur, including a new hanger.
    I have a new found respect for the high elevation riding in Colorado, since we did a chunk of the CO trail above Durango a couple weeks ago. Riding and sleeping above 10,000 feet for 4 days absolutely killed us beach dwellers. BUT, if you LIVE that high you have no excuse!
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  13. #13
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    Bonking ... not feelin' well Can I claim age?

    Yeah, yeah, yeah; even though I live here, the altutude still whacks me; just not as hard as it does you.

    In addition, (OK - bring on the hoots, jeers and flames), I am old - 54.

    Looks like a nice ride there on the CO Trail. We are doing another section of it next weekend - Monarch Crest.

  14. #14
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    Quote Originally Posted by steve47co1
    Yeah, yeah, yeah; even though I live here, the altutude still whacks me; just not as hard as it does you.

    In addition, (OK - bring on the hoots, jeers and flames), I am old - 54.

    Looks like a nice ride there on the CO Trail. We are doing another section of it next weekend - Monarch Crest.
    Haha, don't sweat it. The age disclaimer is not nearly as bad as the rigid/singlespeed disclaimer.

    "I didn't clean that section...but I was on a singlespeed which makes me cool and unusual!"

  15. #15
    Natl. Champ DH Poser/Hack
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    wow man! thats some brutal terrain and i can attest to a flatlander at altitude and the old guy issues. colorado kicked my ass. huge respect dusty and steve. im impressed as hell.
    No, I'm NOT back!

  16. #16
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    Quote Originally Posted by Dusty Bottoms
    Haha, don't sweat it. The age disclaimer is not nearly as bad as the rigid/singlespeed disclaimer.

    "I didn't clean that section...but I was on a singlespeed which makes me cool and unusual!"
    Nice to see you ragging on the rigid/SS crowd too, Dusty.

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