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Discussion Starter · #1 · (Edited)
If anyone else is using stock XT cranks with the outboard bearings on an 09 RIP9, could they post a pic of the clearance between the big ring and the drive-side seat stay for me? Thanks!

(see below for pix of my issue)
 

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Told ya, already had a thread dealing with this, according to the poster who started it (I believe AZmtn) he had to remove the big ring because when torque was applied there was contact. Seems the try at more tyre clearance has created this issue. It may have been noticed by Niner in development and thought "not a problem" since most will use a double ring setup on the RIP9s :skep: Steve or Chris had chimed in on the other thread.

'Cause I'm feeling nice today http://forums.mtbr.com/showthread.php?t=511661
 

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Discussion Starter · #3 ·
I looked at that thread and he doesn't have the same set-up. He's riding LX cranks. The response from Niner was that they've never had the problem in 30 builds. So I'm interested to see how it's working for other people rather than assuming it's a defect, as you do.

You're a nice enough guy, Lynx, but you don't have to patrol every thread.
 

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I don't mean to "patrol", but works not slow, more like dead for me right now, plus my backs giving me the shits, I'm bored and lusting after stuff I can't afford until a year or two down the line and without the ability to go ride, "patrolling" is the closets I can get :D Plus as you said I'm a nice guy and like to help if I can :D

pinkheadedbug said:
I looked at that thread and he doesn't have the same set-up. He's riding LX cranks. The response from Niner was that they've never had the problem in 30 builds. So I'm interested to see how it's working for other people rather than assuming it's a defect, as you do.

You're a nice enough guy, Lynx, but you don't have to patrol every thread.
 

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Discussion Starter · #5 ·
OK, here are the pix of my set-up. This shows that the clearance between the big ring and the chainstay with the suspension unsagged is just over 1/16". I also show that I'm using the drive side spacer (none on the other side). You can see in one of the pictures a bright spot where the chain has been jammed against the chainstay.

What happens in riding is that most of the time it's fine, but then you shift and the chain gets caught between the big ring and the chainstay while the suspension is compressed, and is sucked up ABOVE the chainstay, where it stays once the suspension uncompresses. It is basically impossible to get out at that point without breaking the chain.

I am not very happy about this as I like having the big ring, and I think there is a possible (but remote) safety concern, since this can't be good for the chain and I could see it breaking if you were mashing. Would welcome a further response from Niner.
 

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Discussion Starter · #6 ·
So I spoked to Niner about this and one of the guys there measured the clearance on a bike there and came up with about the same measurement as mine. So it appears that the frame is in spec.

He (?Brian) suggested that chainring wear may be causing the chainsuck and that seems possible since although the chainset isn't that old it has been through a lot of rocks.

I guess I will check for bent and burred teeth.
 

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If I might give a possible solution......unless you have to ride a lot of road to get to the trail or between trails consider going to a double or if you want the tripple go to a compact tripple (patent pending from yours truly :p ) and buy some new chainring in the form of a 40 or maybe 42 for the big ring. My compact tripple will be a 24/34/40 setup. Even using a 7 cogs setup I stil can get more than enough speed without killing myself right now running a 24/38 ring setup and a 34-15 cassette.
 

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Discussion Starter · #8 ·
I like the idea of the compact triple, but I may go to a bash ring if I can't fix it as some of the trails I ride are real ring-bashers.

After talking to Niner I went back to the bike, cleaned it all up and inspected the big ring. There was one nasty inwardly bent tooth on the big ring where I must have augured into a rock. I straightened it out with a pair of pliers until I couldn't feel it with my eyes closed. So we'll see if that does the trick.

I don't believe I'm getting any contact thru frame flex so the only reason for the chain to suck up would be ring-related.

Brian also mentioned that the unsagged clearance may open up slightly with wear (as the shock unsticks I guess).
 

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Discussion Starter · #9 ·
A bit more reading seems to indicate that gritty mud + worn chainrings = chain suck. The last ride was the epitome of gritty mud, wrangling the RIP9 through hub deep gunk. My chainrings are not at all hooked but as I said above, one was bashed inward through rock contact. I'll post results of the next ride, which will most likely be the same conditions.

(I should say that I took the 07 version with the same chainrings to hell and back and never had an issue).
 

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different, yet the same chainline..

Yes, LX and XT outboard cranks are different but both operate off a 50mm chainline. One other option I posted was to install a 2nd spacer on the driveside cup to give you more clearance. The only issue I could think of is the more acute chainline you'd have if you run middle ring/large cog combination. Like I stated in my thread, I just pulled the large chainring and installed a bashguard. It is BTW an "All Mountain" bike.:D
 

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pinkheadedbug said:
You're a nice enough guy, Lynx, but you don't have to patrol every thread.
What lead you to that strange conclusion?





edit: I thought I should mention pink, best signature ever, still gets a smile after reading it for the 400th time.
 

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And yet I seem to have contributed something helpful to his thread, which is in contrast very different to your fantasticly helpful post :rolleyes: :headphones: :ciappa:
CaveGiant said:
What lead you to that strange conclusion?.
pinkheadedbug I like the idea of the compact triple, but I may go to a bash ring if I can't fix it as some of the trails I ride are real ring-bashers
.
 

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I'm curious Pink...

If the rear triangle moves up and back when it compresses on the trail, couldn't you compress the suspension enough with your body weight so a budy could slip the chain back out? If alone, compress by hand and yank? You probably tried it, just thought I'd through it out there.
 

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Discussion Starter · #14 ·
Yeah I thought of that -- AFTER the ride. I think with a buddy it would be doable. Alone it might be a bit tricky but worth a try.

I use powerlinks so it's not that much of a deal to break the chain.
 

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LyNx said:
And yet I seem to have contributed something helpful to his thread, which is in contrast very different to your fantasticly helpful post :rolleyes: :headphones: :ciappa:
I suppose it does make a change from your usual patronising posts.

I am sorry to hear work is slow at the moment, it's a shame when bad things happen to good people.
 

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............OR, carry a shock pump with you and if it happens again just deflate the shock and get the chain out, then re-inflate ;) Once there's suspension on a bike I'm riding I always have 2 pumps with me. I normally don't have to use either of them, but it's amazing how many of the people I ride with do :skep: :madman:

pinkheadedbug said:
Yeah I thought of that -- AFTER the ride. I think with a buddy it would be doable. Alone it might be a bit tricky but worth a try.

I use powerlinks so it's not that much of a deal to break the chain.
CG, appreciate the thought and taken with sincerity ;)
 

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Discussion Starter · #17 ·
I'm thinking about your compact triple, Lynx. I'm one of those guys who changes as much on the front as the back, and a closer set of ratios could work for me.

When I was riding slickrock I was really hurting for a smaller gear, in line with the 26ers. So I'm thinking of notching down the whole crankset and also closing up the ratios.

Anyone done this?
 

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I see no reason why it wouldn't work, but myself haven't found (once conditioning is there) the need for anything smaller than a 22t granny (personally prefer a 24t), but a 20/30/40 would shift very nice and offer loads of top end and low end. Check the recent threads somoene else was doing exactly this. And the guy who makes chainrings is working on a 40t with ramps. Check the 29er forum, saw it somewhere recent , maybe in a RIP9 related thread.
pinkheadedbug said:
I'm thinking about your compact triple, Lynx. I'm one of those guys who changes as much on the front as the back, and a closer set of ratios could work for me.

When I was riding slickrock I was really hurting for a smaller gear, in line with the 26ers. So I'm thinking of notching down the whole crankset and also closing up the ratios.

Anyone done this?
 

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Pink,
I did the exact same thing on today's ride. I sucked the chain above the chainstay, I had to break the chain to get it back past the big ring. I'm running a brand new chain on brand new rings, 44T big ring. I'm not too stoked about the nasty gouge, the same as you show in your pic.
 

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I'd appreciate if some of the Niner-guys could comment on this. I'm expecting my RIP to arrive the next few days and had planned building it with 2009 XT. Not too keen on having to deal with this on every ride.

Edit: OK, just saw the thread Lynx linked to.
 
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