what should I look for? Skipping out back!- Mtbr.com
Results 1 to 22 of 22
  1. #1
    mtbr member
    Reputation: rdbandkab's Avatar
    Join Date
    Dec 2010
    Posts
    55

    what should I look for? Skipping out back!

    Hi all,

    I'm trying to figure out what in my drive line is creating a skip when under heavy torque...
    New Trek Stache 7 29+ converted to SS. 30t stock ring on front, Surly 20t rear cog. Everything is new including the chain. I'm not sure what hub shell Trek is using for this Boost 148 hub shell (Bontrager?), but there's a shimano (3 pawl) freehub installed.
    Does it matter what combination of spacers you use to get the chain in line?? IE Would using a lot of skinny spacers be more likely to create a freehub skip than say using 2 or 3 thicker spacers?
    The chain and rings look to be in great alignment.


    Any input would be appreciated.


    rdb

  2. #2
    SS Pusher Man
    Reputation: mtnbikej's Avatar
    Join Date
    Sep 2001
    Posts
    7,479
    Is the stock ring up front ramped and pinned for 2x system?

    Spacers on the freehub make no difference....my cog is spaced out with a bunch of 5mm spacers removed from older 8 spd cassettes with out issue.

    It could be the actual freehub that is skipping under heavy load.

    Otherwise, make sure your chainline is as straight as possible. Also, make sure your chain tension is pretty tight. Too much slack and the chain can climb up on the teeth on the cog or ring.

    Are you running a chain tensioner? Sometimes too loose or too tight a spring can cause skipping.

    Also, what chain are you running? 3/32 or 1/8"
    Bicycles donít have motors or batteries.:nono:

    Ebikes are not bicycles :nono:

  3. #3
    mtbr member
    Reputation: rdbandkab's Avatar
    Join Date
    Dec 2010
    Posts
    55
    Thanks for the input!!

    The stock ring is for a 1 x 11. I'll check the chain tightness again. It isn't "piano wire" tight or anything.... I try to leave it a little slack.

    *The chain looks like a KMC DX10 xsp. Is there a preferred size for single speed? One that's less prone to have issues with cog sizes and etc...?

    I have a new Sram pc-971. Maybe I'll toss that one on.

    Thanks!

  4. #4
    SS Pusher Man
    Reputation: mtnbikej's Avatar
    Join Date
    Sep 2001
    Posts
    7,479
    Quote Originally Posted by rdbandkab View Post
    Thanks for the input!!

    The stock ring is for a 1 x 11. I'll check the chain tightness again. It isn't "piano wire" tight or anything.... I try to leave it a little slack.

    *The chain looks like a KMC DX10 xsp. Is there a preferred size for single speed? One that's less prone to have issues with cog sizes and etc...?

    I have a new Sram pc-971. Maybe I'll toss that one on.

    Thanks!


    I run the same KMC chain on my SS.

    In the bike stand turn the pedals and see if you can push the chain off the cog or ring. If you can, the chain may be too loose.

    Also, the N/W ring may be part of the problem if the chainline is not perfect.
    Bicycles donít have motors or batteries.:nono:

    Ebikes are not bicycles :nono:

  5. #5
    mtbr member
    Reputation: rdbandkab's Avatar
    Join Date
    Dec 2010
    Posts
    55
    Cool. It sounds like the chain should be good then. I'll give the whole system another look..
    *I still wonder about the freehub shell/Shimano freehub on the Boost 148 system......

    Thanks again!

  6. #6
    One Gear
    Reputation: .40AET's Avatar
    Join Date
    Jun 2007
    Posts
    1,070
    Check the chain for a tight or stiff link. If you put the SRAM chain on, check that too before it's installed. Good luck

  7. #7
    mtbr member
    Reputation: DualRollers's Avatar
    Join Date
    Apr 2014
    Posts
    428
    Doesn't the Stache 7 come stock with an XD driver? If it has a Shimano freehub on it then it must have been converted. Are you sure the conversion was done properly? The pawls might be installed incorrectly and are causing it to slip.

  8. #8
    mtbr member
    Reputation: rdbandkab's Avatar
    Join Date
    Dec 2010
    Posts
    55
    Yes. The Stache does come stock with the XD. I have confidence that the conversion was done correctly (at the shop). I just wonder about the compatibility of the Shimano freehub with the stock shell and star ratchet ring (Sram?)..

    *General question: There are three pawls on the freehub(held on and sprung by a "c-clip" piece of thin gauge wire). Is this system designed to have all pawls engage into the ratchet ring at the same time, or are they slightly staggered to allow for quicker engagement?

  9. #9
    mtbr member
    Reputation: DualRollers's Avatar
    Join Date
    Apr 2014
    Posts
    428
    I guess I worded that wrong, that's basically what I was saying. Some pawls are not compatible with certain ratchet rings and will cause hub failure. If they put new pawls in with the Shimano conversion and they aren't right for the ratchet ring that's in the factory hub then that's probably your issue.

  10. #10
    mtbr member
    Reputation: rdbandkab's Avatar
    Join Date
    Dec 2010
    Posts
    55
    I'm assuming that the pawls that are on the Shimano freehub are generic ones.. They're kind of "stubby" looking in comparison with the sharp angles of the ratchet ring.

    The freehub is this type:

    Name:  s-l300.jpg
Views: 659
Size:  9.7 KB

  11. #11
    nothing to see here
    Reputation: Stevob's Avatar
    Join Date
    Feb 2009
    Posts
    3,271
    Skipping on a 20t Surly is cause for concern, as it's a pretty rock solid setup for the rear. I'd be checking chainline, chainring roundness creating tight/loose spots, frame flex as possible causes. Suspecting that the freehub, if it's installed correctly, and has no play, would not be the culprit. Same goes for the spacers.

    Left of field cause might be a broken axle.
    I see hills.

    I want to climb them.

  12. #12
    mtbr member
    Reputation: rdbandkab's Avatar
    Join Date
    Dec 2010
    Posts
    55
    Yea..... Looking at the chain and cogs, it's hard to imagine anything being able to skip. Lots of teeth to hook onto! It's all new..
    I'm suspecting the Sram(?) shell and Shimano freehub aren't totally happy with each other.
    Thanks all for the input.....

  13. #13
    mtbr member
    Reputation: DualRollers's Avatar
    Join Date
    Apr 2014
    Posts
    428
    That would definitely be my focal point if I were in your situation... and also, I don't know about the Stache 7 but the hub shell on my Stache 5 is made by Bontrager. It just has a generic "BOOST 148" printed on the inside of the hub. If yours is the same, you may be able to call Trek/Bontrager and ask them about compatibility.

  14. #14
    mtbr member
    Reputation: rdbandkab's Avatar
    Join Date
    Dec 2010
    Posts
    55
    I thought it may be a Bontrager (their go-to supplier)... Not sure where I got Sram..
    Yep.. Just "Boost 148" on it.
    I believe the LBS went with the Trek suggested parts, but I'm not too impressed with the mid-level Bonti stuff anymore.

  15. #15
    mtbr member
    Reputation: DualRollers's Avatar
    Join Date
    Apr 2014
    Posts
    428
    Bontrager is actually Treks house brand of parts, same company. I'm actually not a huge Trek fan because of the Bontrager parts. This is my second Trek (the first was a Domane road bike) and i've been less than impressed with the Bontrager stuff that came on both. The only reason I went with the Stache is because the geo is spot on and it rides amazing. However, I am currently in the process of finding a new rear hub (likely going with a Hadley) because the Bontrager rear is probably the sloppiest hub ive ever ridden.

    I feel like Trek has some pretty innovative stuff going on with their frames, but their sub company is really holding them back. Specialized house parts feel a lot more solid to me.

  16. #16
    mtbr member
    Reputation: rdbandkab's Avatar
    Join Date
    Dec 2010
    Posts
    55
    Amen. I just hate having to go buy a new hub for a brand new bike.. ARRGGG!
    I've seen ready built 12x148 MuleFuts with Sram/Shimano (splined freehub) for sale for a little bit more than having a new hub laced up to my rim.

  17. #17
    mtbr member
    Reputation: floorguy724's Avatar
    Join Date
    Apr 2004
    Posts
    350
    I've been having the same problem with my Stache 5 that's setup SS.

    Under heavy load and a lot of torque, it skips out back. I've narrowed it down the dropouts. They're adjustable (on the 5 anyway) and you just have to tighten them down a bit. On my 5, there is a 20 mm nut that has to be tightened as well as the thru axle.

    Just tightened them again and will hopefully get to ride it tomorrow?

    Sent from my Galaxy Note 5

  18. #18
    mtbr member
    Reputation: DualRollers's Avatar
    Join Date
    Apr 2014
    Posts
    428
    Just a heads up, it looks like Chain Reaction is clearing out their Hope Pro Evo 2 hubs since the 4s are dropping soon. I just got a Boost rear hub and 36 DT Swiss comp DB spokes for ~$250... Couldn't pass it up, its a great deal if you know how to build your own wheels.

  19. #19
    the air is thin up here..
    Reputation: noot's Avatar
    Join Date
    Jul 2008
    Posts
    738
    Quote Originally Posted by DualRollers View Post
    Bontrager is actually Treks house brand of parts, same company. I'm actually not a huge Trek fan because of the Bontrager parts. This is my second Trek (the first was a Domane road bike) and i've been less than impressed with the Bontrager stuff that came on both. The only reason I went with the Stache is because the geo is spot on and it rides amazing. However, I am currently in the process of finding a new rear hub (likely going with a Hadley) because the Bontrager rear is probably the sloppiest hub ive ever ridden.

    I feel like Trek has some pretty innovative stuff going on with their frames, but their sub company is really holding them back. Specialized house parts feel a lot more solid to me.
    All mid-range in-house bike parts are iffy, don't judge bontrager based on it.

    Bontrager is without doubt the best "in-house" company of them all. Their higher end stuff is fantastic across the board. Saddles, rims, tires, etc. It's not just rebranded Chinese crap, and its often lighter than anything else. That said, I have blown up a Bontrager hub too.
    2017 Transmission Smuggler
    2015 Kona Paddy Wagon
    www.mngnt.com

  20. #20
    mtbr member
    Reputation: DualRollers's Avatar
    Join Date
    Apr 2014
    Posts
    428
    Maybe my stuff has been on the lower end, very possible... I have just had way better luck with Specialized house brand stuff. I will say though, the Chupacabra tires from Bontrager have been amazing up to this point.

  21. #21
    mtbr member
    Reputation: rdbandkab's Avatar
    Join Date
    Dec 2010
    Posts
    55
    I think it's more of a Trek issue than Brontrager.
    In order for the Stache 5 or 7 to be converted to a single speed (the selling point for me), a freehub with questionable compatibility to the existing hub shell had to be added to the equation. In this case, they "spec'd" a mid level hub that was probably up to the task for the majority of riders. But when that hub starts causing issue for the minority of riders (skipping and the like), I hate to have to put more money out to rectify the situation.
    AND I'm running out of confidence when it comes to cranking up a hill!

    *Don't get me wrong....I absolutely love the bike aside from this issue.
    Last edited by rdbandkab; 01-08-2016 at 09:08 AM.

  22. #22
    mtbr member
    Reputation:
    Join Date
    Sep 2010
    Posts
    80
    Did you guys ever nail down the problem here? I'm considering converting my stock Stache 9 29+ to a SS, but am concerned with complications like this. If I understand correctly rdbandkab needed to put a Shimano freehub body on his stock rear hub in order to accommodate the Surly cog (correct?), and that there may be some sort of incompatibility with the Shimano freehub body and the Bontrager hub? If so, what's the solution? Sounds like you either need to keep the original freehub and find a compatible cog for it, or get a whole new rear hub/wheel combo that's compatible with Shimano/Surly?

    Thanks,
    Sean

Similar Threads

  1. Horribly skipping chain: front or back gears?
    By flyboyfish in forum Drivetrain - shifters, derailleurs, cranks
    Replies: 18
    Last Post: 08-16-2013, 03:50 PM
  2. Chain skipping or Freehub skipping?
    By jbsmith in forum Singlespeed
    Replies: 8
    Last Post: 09-09-2012, 09:42 AM
  3. Skipping out!
    By schnauzers in forum Riding Passion
    Replies: 14
    Last Post: 05-05-2012, 03:37 PM
  4. Skipping?
    By Luke Pinneo in forum Drivetrain - shifters, derailleurs, cranks
    Replies: 1
    Last Post: 06-15-2011, 04:10 PM
  5. skipping
    By Justin Credible in forum Drivetrain - shifters, derailleurs, cranks
    Replies: 4
    Last Post: 06-15-2011, 02:00 PM

Members who have read this thread: 1

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

THE SITE

ABOUT MTBR

VISIT US AT

© Copyright 2019 VerticalScope Inc. All rights reserved.