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  1. #1
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    Altitude 790 front shifting

    Anyone else having issues with the front shifting? 2x10 set up, stock.

    Two of my customers are complaining about dropping the chain and it getting sucked into the chainstay area. It seems top be happening when shifting from the small ring up to the big ring. The chain starts to engage the ramps and starts climbing momentarily, but then snaps off and jumps to the small ring, often overshooting it and jamming up down below.


    I'm wondering if the clutch type 2 derailleurs have anything to do with this. Seems like it might.

    If I adjust cable tension and der. stop on the big ring too far out it overshoots and drops tot eh outside. Adjust to where it should be perfect and it seems this scenario happens.

    (as a side note....I've been working on MTB's professionally for the past 20 years, so I know how to set up a der. properly. This just has me a bit stumped.)
    www.velocitybicycles.comWhere customers become friends, not simply a dollar sign.

  2. #2
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    I'm still having issues with mine I got a hold of RM they said switch the shifter to 3x then adjust. Seemed to help but its still not crisp.Help Please!!!

  3. #3
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    I have a 750 altitude that I had converted to full XT (minus the front derailleur, so stock X7 is still in place) and have been dealing with front shifting issues as well. I have not had the chain derail towards the inside of the chainrings, but had to play with the 2x and 3x switch on the shifter as well as the adjustment to find the sweet spot between not shifting at all or kicking the chain off the outside of the big ring. I have had some success with getting the bike to shift ok, but there are some quirky aspects to this setup:
    1) my RH crank arm was loose on the splines from new so until that was resolved, consistent adjustment was impossible.
    2) no matter what I do, the front derailleur will not retract enough to 100% clear the chain, so with a small front chainring and the 34t selected on the cassette, I get a slight rub between the chain and the derailleur. This is not a cable tension issue or a limit screw issue... it seems as though the crank needs to be spaced away from the BB, or the derailleur mounting pad needs to have some material removed.
    3) I bought an MRP XCG guard to attempt to help prevent any damage caused by the chain derailing to the inside, but the clocking of the ISCG tabs on the frame will not allow me to install the guide without modifying it (new mounting holes)

    Seeing this thread, I'm starting to wonder how isolated this shifting issue really is....

  4. #4
    Cleavage Of The Tetons
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    I removed some material from the inside (on the frame), and now mine works flawlessly.
    I'll post pics tomorrow. It was mostly paint, but a little aluminum as well.
    "We LOVE cows! They make trails for us.....

    And then we eat them."

  5. #5
    orthonormal
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    Quote Originally Posted by Internal14 View Post
    Anyone else having issues with the front shifting? 2x10 set up, stock.

    Two of my customers are complaining about dropping the chain and it getting sucked into the chainstay area. It seems top be happening when shifting from the small ring up to the big ring. The chain starts to engage the ramps and starts climbing momentarily, but then snaps off and jumps to the small ring, often overshooting it and jamming up down below.


    I'm wondering if the clutch type 2 derailleurs have anything to do with this. Seems like it might.

    If I adjust cable tension and der. stop on the big ring too far out it overshoots and drops tot eh outside. Adjust to where it should be perfect and it seems this scenario happens.

    (as a side note....I've been working on MTB's professionally for the past 20 years, so I know how to set up a der. properly. This just has me a bit stumped.)
    Yup, same problem for me. Is it only the 790 or is it a problem on other models too? If it's only the 790, maybe the SRAM X.0 chainrings are the culprit. The only other thing I notice that's different about this bike from others I've owned is that the front derailleur mounts to the swingarm instead of the main frame. If that's the problem, the Shimano equipped models should suffer as well.

    One thing I tried has actually helped quite a bit. I had been using K. Lewis Enterprises A.T.B. Lube and recently gave ProLink Extreme a try after getting some free samples at Sea Otter. I still try not to up shift in front when I'm torquing really hard but it has really reduced the problem. This makes me think it's the chainrings and not the frame.
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  6. #6
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    All the current Rocky FS bikes use the swingarm mounted FD (Element (26+29), Instinct and Slayer, so it is a reasonably well sorted approach. But it may be that facing the mounting bosses would be necessary to clear the paint off. I don't remember now if the front derailleur mounts were faced on my Element 70 MSL frame.

    Edit: found the photo in the assembly manual showing the paint was masked off on those front derailleur mount bosses
    Attached Thumbnails Attached Thumbnails Altitude 790 front shifting-fd-mounts.jpg  

    I'm a member of NSMBA and IMBA Canada

  7. #7
    orthonormal
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    Quote Originally Posted by rockyuphill View Post
    All the current Rocky FS bikes use the swingarm mounted FD (Element (26+29), Instinct and Slayer, so it is a reasonably well sorted approach. But it may be that facing the mounting bosses would be necessary to clear the paint off. I don't remember now if the front derailleur mounts were faced on my Element 70 MSL frame.

    Edit: found the photo in the assembly manual showing the paint was masked off on those front derailleur mount bosses
    From a little more reading, it sounds like the problems others are having with the Shimano drivetrains is different than what happens with the SRAM X.0 drivetrain on the 790, so you're right; it's probably not the swingarm mount.

    I'm wondering if maybe the spacing between the ISCG tabs and the smaller chainring in combination with SRAM's redesigned chainring ramps is the issue. When the chain drops to the inside while shifting to the larger chainring, it gets wedged in between the ISCG tab and one of the inner chainring bolts. Maybe the chainring ramps would eventually lift the chain onto the larger ring if it wasn't wedged in there.
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  8. #8
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    It's funny. Two customers with the 790MSL have no issues. Two others though ARE having problems.

    Talked to SRAM and they're sending out a new set of cranks to see if that takes care of the problem.

    I'm guessing maybe an issue with the cranks/rings ont eh OEM scale of things might have gone array. At least that's what SRAM may be thinking.
    www.velocitybicycles.comWhere customers become friends, not simply a dollar sign.

  9. #9
    orthonormal
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    Quote Originally Posted by Internal14 View Post
    It's funny. Two customers with the 790MSL have no issues. Two others though ARE having problems.

    Talked to SRAM and they're sending out a new set of cranks to see if that takes care of the problem.

    I'm guessing maybe an issue with the cranks/rings ont eh OEM scale of things might have gone array. At least that's what SRAM may be thinking.
    Mind if I Have the shop where I bought mine (Cyclepaths in Truckee) give you a call?
    The glass is twice as large as it needs to be

  10. #10
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    M6x10 Bolts on my Altitude 790

    I installed 2 M6x10 hex head bolts in 2 of the ISGC05 holes in case the chain flops off to the inside. Had to cut one bolt shorter. It has derailed once so far, and the bolts caught the chain nicely with no damage.

    I occasionally have the chain derail to the outside. It's time for my one-month tune up, so I'll let the LBS deal with that.

  11. #11
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    Mike's Velo City, 41 Main St. Winters, CA
    (530) 795-3454

    Feel free to have them give me a ring.
    www.velocitybicycles.comWhere customers become friends, not simply a dollar sign.

  12. #12
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    Hey all, so my genius LBS who only does Rocky has discovered the bottom pivot seems very close. The bike flexes a cm left and right. When pushing down on pressure the chain moves over to the right. This causing the chain to overshoot and all sorts of shifting issues. This seems new and make be due to the shop I purchased it from not fitting the pivot correctly. I'm waiting to hear once the bike has been striped to see. However I'm confident this is the issue. Once confirmed I will update.

  13. #13
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    Quote Originally Posted by spongemtb View Post
    Hey all, so my genius LBS who only does Rocky has discovered the bottom pivot seems very close. The bike flexes a cm left and right. When pushing down on pressure the chain moves over to the right. This causing the chain to overshoot and all sorts of shifting issues. This seems new and make be due to the shop I purchased it from not fitting the pivot correctly. I'm waiting to hear once the bike has been striped to see. However I'm confident this is the issue. Once confirmed I will update.
    Just an update, after fitting a new pivot the problem has NOT been resolved. Not sure what's next...

  14. #14
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    In my case, the problem turned out to be the shifting ramps on the SRAM X0 chainrings. There was just a tiny bit of extra material there and as the chain wore them down just a little, my front shifting issues disappeared.
    The glass is twice as large as it needs to be

  15. #15
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    Quote Originally Posted by andy f View Post
    In my case, the problem turned out to be the shifting ramps on the SRAM X0 chainrings. There was just a tiny bit of extra material there and as the chain wore them down just a little, my front shifting issues disappeared.
    ok the problem is still around. Does anyone know if the Truvativ 36T MTB Chainring has issues with the Raceface turbine?

  16. #16
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    My Altitude 750 has developed front shifting issues with approx 40 hours riding.
    Shifting to big sprocket.
    Shifting cable was stiff especially at the bend at the bottom of the frame.
    Cleaned up inner and outer and seems much better.

    I'm going to change to the Gore Ride-On for front and back derailleur.
    Can someone confirm if this kit will cater for that?
    Thanks

    Happy New Year to all you RM riders!
    Altitude 750 2014

  17. #17
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    That SRAM kit is the fully sealed Gore Ride On one, that should work for the Altitude. It makes a huge difference, I just did that with my Instinct 999 MSL build and it's night and day difference compared to my alloy Instinct. With the Gore cable kit, the old "measure twice - cut once" platitude should be changed to "measure three times - cut once" to avoid a lot of cursing.
    I'm a member of NSMBA and IMBA Canada

  18. #18
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    Quote Originally Posted by rockyuphill View Post
    That SRAM kit is the fully sealed Gore Ride On one, that should work for the Altitude..
    Thanks,i'll give it go!
    Altitude 750 2014

  19. #19
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    Quote Originally Posted by Beiciwr64 View Post
    Thanks,i'll give it go!
    Here's my commentary on doing the Gore Ride On installation on my Instinct 999 MSL

    Running internal Gore Ride On cables
    I'm a member of NSMBA and IMBA Canada

  20. #20
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    Back to the front shifting problem, the bottom pivot was replace. Bearings, plus 4 bushings to make it more stiff plus my cassette and change needed replacing. I put a new Raceface chainring on and all sorted.

    Funny because after all of this hassle I've gone 1x10 with a 32t Raceface Narrow / Wide and so far been able to climb everything.

  21. #21
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    I have a RM Altitude 770 with the Shimano XT 2x10. Won't shift in front with any weight on the bike. Shifts perfectly when on the mechanic's stand or if I hop off of it and spin the cranks. RM said there was an issue with the bottom bracket cable guide and sent a metal replacement one. Same issue is happening, the suspension pulls the cable out and doesn't allow the bike to shift. Thinking of going to 1x11 to resolve the issue.

  22. #22
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    I went to a 1X9 with a twist grip. I had my other bike set up that way. I don't think I'll ever run a 2X again.

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