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  1. #1
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    chain dropping woes....help!

    having major issues with dropping the chain(from the middle to small ring) when using lots of torque and riding over choppy terrain on my hardtail. The front derail is adjusted so it is virtually touching the chain but it still drops under power. I'm running a long cage rear with 3 rings in the front. Should I try a bashguard/shortening chain or just go straight to a chainguide?

  2. #2
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    Quote Originally Posted by claycooper
    having major issues with dropping the chain(from the middle to small ring) when using lots of torque and riding over choppy terrain on my hardtail. The front derail is adjusted so it is virtually touching the chain but it still drops under power. I'm running a long cage rear with 3 rings in the front. Should I try a bashguard/shortening chain or just go straight to a chainguide?
    You should try shifting while not under load, bikes were not designed to work this way. You will just end up wrecking things if you continue to do this.
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  3. #3
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    Quote Originally Posted by GearHead
    You should try shifting while not under load, bikes were not designed to work this way. You will just end up wrecking things if you continue to do this.

    that's the problem, i'm not shifting. I'm just pedaling hard while going over bumps. If I put it in 2-5 and ride off a curb while pedaling hard, the chain will jump down to the granny ring. The chain is also correct(2 links added to minimum possible length), so i can't figure it out. I'm using an external bearing BB, so maybe I'll try removing a spacer.

  4. #4
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    Is it a RaceFace crank you have?

    The other option is shifting the crank over to the non-drive side to reduce the chainline and this hould solve the problem.
    Last edited by GearHead; 01-08-2006 at 04:56 PM.
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  5. #5
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    Quote Originally Posted by GearHead
    Is it a RaceFace crank you have?

    The other option is shifting the crank over to the non-drive side to reduce the chainline and this hould solve the problem.

    shimano LX external BB crank, x gen front der, 9.0 rear der, 970 cassette

  6. #6
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    Funny that u mentioned this, im having the same damn problem. Im afraid to put torque on my chain now because i think its gonna slip out which it does. I replaced my middle ring thinking it was a problem with that. I have not gone to the trails yet though, ill let you know what happends. Im gonna change the chain if it keeps happening... not sure what i will do after that.

  7. #7
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    Its still screwed up even with the new ring.. Its weird cause the big ring and my granny ring hold the chain perfectly with whatever torque i put on it. Middle ring if i hit a pebble with some strain on the chain it starts to go crazy.

  8. #8
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    Quote Originally Posted by lobos8403
    Its still screwed up even with the new ring.. Its weird cause the big ring and my granny ring hold the chain perfectly with whatever torque i put on it. Middle ring if i hit a pebble with some strain on the chain it starts to go crazy.
    What crank and chain are you using?
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  9. #9
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    No one's asked a key question, what bike(s) are you guys riding? I know using the XT HT2 crankset on my GIANT Trance I had to use only 1 spacer on the drive side instead of the recomended 2 to get the correct chainline w/ no probs.
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  10. #10
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    I had a similar problem and the culprit was a worn middle ring. It was only two months old and I couldn't believe that this was the problem. A new cassette and chain later......I was proved wrong!
    It's only pain......

  11. #11
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    Sworks hardtail with an xt 760 crankset. I have an xt chain on there right now. I have one spacer driveside and two spacers non drive. Like i said before i changed the middle ring to a brand new one and both the granny and the big ring hold the chain flawlessly but the middle is all screwy.

  12. #12
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    riding a banshee scirocco hardtail, all new components, hone(same as lx) HT2 crankset, x-gen front derailluer. I'm not sure how to tell if I need both spacers or not??? I'm thinking about getting an MRP LRP if I can't fix the problem, I never had this problem on my old bike.

  13. #13
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    Quote Originally Posted by lobos8403
    Sworks hardtail with an xt 760 crankset. I have an xt chain on there right now. I have one spacer driveside and two spacers non drive. Like i said before i changed the middle ring to a brand new one and both the granny and the big ring hold the chain flawlessly but the middle is all screwy.
    Don't quite know what to tell you as you've done exactly what I would suggest and did with mine. Only other thing I can tell you is that the "ultimate" chainline is sposed to be 45mm, so you could try removing the spacers altogether from the drive side and see if that helps. What brand chainring did you use to replace the middle ring with?


    claycooper riding a banshee scirocco hardtail, all new components, hone(same as lx) HT2 crankset, x-gen front derailluer. I'm not sure how to tell if I need both spacers or not??? I'm thinking about getting an MRP LRP if I can't fix the problem, I never had this problem on my old bike.
    Only thng I could suggest is to try playing with the spacers on the drive side and see of that helps. According to Shimano the correct setup for the new HT2 cranksets is as follows....... If you have a bike with a 68mm BB then you need to use all 3 spacers, w/ 2 on the non drive-side and 1 of the drive side. If you're using a bike w/ a 73mm BB you're sposed to use 1 spacer on the non drive side. However Shimanos recomendation gives you a 50mm chainline (for the 68mm BB at least) which is not even close to ultimate for most bikes. If you don't knwo about BB widths, it's simple just get a ruler and measure the width
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  14. #14
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    Quote Originally Posted by LyNx
    Don't quite know what to tell you as you've done exactly what I would suggest and did with mine. Only other thing I can tell you is that the "ultimate" chainline is sposed to be 45mm, so you could try removing the spacers altogether from the drive side and see if that helps. What brand chainring did you use to replace the middle ring with?



    Only thng I could suggest is to try playing with the spacers on the drive side and see of that helps. According to Shimano the correct setup for the new HT2 cranksets is as follows....... If you have a bike with a 68mm BB then you need to use all 3 spacers, w/ 2 on the non drive-side and 1 of the drive side. If you're using a bike w/ a 73mm BB you're sposed to use 1 spacer on the non drive side. However Shimanos recomendation gives you a 50mm chainline (for the 68mm BB at least) which is not even close to ultimate for most bikes. If you don't knwo about BB widths, it's simple just get a ruler and measure the width

    the install instructions that came with the crank showed 2 spacers drive, 1 non drive which is how I had it and it gave me a 50mm. I just switched them around, so now it's 47.5mm. Unfortunately the BB has a sleeve that prevents less than 3 total spacers being used on a 68mm BB. I don't know if anyone has had success modifying this plastic sleeve to run fewer spacers, but maybe I'll try that. Without modifying the sleeve, I can't take them all off of the drive side because that wont leave enough threads exposed with 3 spacers on the non-drive side.

  15. #15
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    Quote Originally Posted by claycooper
    the install instructions that came with the crank showed 2 spacers drive, 1 non drive which is how I had it and it gave me a 50mm. I just switched them around, so now it's 47.5mm. Unfortunately the BB has a sleeve that prevents less than 3 total spacers being used on a 68mm BB. I don't know if anyone has had success modifying this plastic sleeve to run fewer spacers, but maybe I'll try that. Without modifying the sleeve, I can't take them all off of the drive side because that wont leave enough threads exposed with 3 spacers on the non-drive side.
    Don't run less than the 3 spacers, but did do some mods on the tube. Measure your BB's width carefully and then assemble the bearing & tube and measure the width it gives you between the bearings and I would bet you'll find it's actually a bit wider than your BB. Therfor you can sand down one of the spacers you're running (and use it on the non drive side) and prob make it 1mm thinner. I measured and determined the measurements and actually sanded down t1 spacer over 1.5mm and did a bit of sanding on the tubes end. It's plastic and easy to modify. I have tried running the thin (roughly 1.2mm spacer on the drive side, but found I really didn't need it that 47.5mm was workng fine and kept my feet better aligned i regards to the frame centre.
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