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Chain suck

andyturner28andyturner28 Posts: 1,225
edited June 2008 in MTB workshop & tech
I have an Inbred 456 with 07 XT cranks and a Race Face outer ring, with 2 BB spacers driveside and one non driveside, and i am getting a stupid amount of chain suck, and twice now this has resulted in the chain quick links coming apart, depositing themselves on the muddy trail and it taking me 10 minuts to find the bloody things! I am assuming it is caused in my case by the very small gap between the outer ring and the chainstay, but is there anything i can buy to go on the chainstay to stop the chain getting jamed in there, or could i run it with only one BB spacer on the driveside so there is no chance of the chain getting in there at all? I'd rather not do the latter though as this would mess the chain line up.
Are the Race Face rings known to cause chain suck? I only ran it with a Shimano outer ring for one ride after building the frame up, so i have no comparison to go on.

Cheers,

Andy.

Posts

  • nicklousenicklouse Posts: 81,520 Lives Here
    chain suck is caused by worn parts.

    sounds like you have a different problem.

    the RF rings are 9spd?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • andyturner28andyturner28 Posts: 1,225
    Everything is new except for the granny ring, which dosn't get that much use round here. Only the outer ring is a Race Face, the rest are Shimano. I have never suffered from chain suck before, basically either when i am changing from middle to outer ring or when i am already in the outer ring and i go over a realy bumpy section, the chain somehow gets jamed in between the outer ring and the chainstay. The frame is under 2 months old and there is no paint left on the chainstay immediately behind the outer ring. The chain couldn't be causing it could it? It is a KMC X9 gold, and i have one of those crappy chain connectors which you have to bend to snap into place from when i cut the chain too short and that is all i could get at the time. It is definately for a 9spd chain though. Any other ideas as it is driving me mad, and i have a very long ride coming up in a few weeks.

    Andy.
  • newbiketimenewbiketime Posts: 86
    Suck is more often from small to middle so just be positive why you are getting it. If you can pit the bike in a stand and fly through the gears and see what its hanging up on. XT middle rings have a habit of hanging on the steel pins used for pickup when the alloy round it is dug out by the chain or the pin it self is bent. Also mixing rings can some times induce it die to the way things end up lining up. SRAM chains more so the hollow pin some how tend to cure it for some people, cant tell you why but we have a team at work that does 24hour events and all got suck and all now use SRAM chains and cheap steel middle rings on the XT chain sets and it appears to have cured it. A lot of cheap FSA and cheaper Race Face chainsets tend to get chain suck a little more than there more expensive counterparts. Front mechs as well make a huge difference. I would not recommend anything less than a Deore. Also the mechs that have the lower clamp tend to work better if your getting suck. But really so much can do it, you just have to work through your bike methodically till you work out what’s doing it. My last bike simply has a lose chain ring bolt and that was doing it.
  • andyturner28andyturner28 Posts: 1,225
    Well i have an 08 XT front mech with the lower clamp, so i can rule that one out. I might get a Race Face middle ring and see if that helps if mixing rings can sometimes cause it. I might also try and make something i can mount on the chainsty to stop the chain getting stuck in between. Can't imagine it would be that hard, just a bit of wedge shaped ally wrapped and secured around the chainstay should do it. Has anyone else tried this?
  • mr mangosmr mangos Posts: 174
    Not sure if that'll fix the problem by the sounds of it. The chain shouldn't be anywhere near getting jammed between the big ring and the chainstay. You'd be better off trying to find out why it's happening in the first place.

    I'm having difficulty visualising how your chain can get stuck there without coming off completely.
  • andyturner28andyturner28 Posts: 1,225
    mr mangos wrote:
    Not sure if that'll fix the problem by the sounds of it. The chain shouldn't be anywhere near getting jammed between the big ring and the chainstay. You'd be better off trying to find out why it's happening in the first place.

    I'm having difficulty visualising how your chain can get stuck there without coming off completely.

    I know, the chain when it is on the big ring is miles from the chainstay, so i haven't got a clue! The only thing i can think of doing is buying lots of Powerlinks so i am not comppletely stuffed the next time it rips one off, which isn't ideal! I'll have to try and gerry rig some sort of stand in the garage and try and replicate it.
  • stubsstubs Posts: 5,001
    have you had the bottom bracket faced I have a on-one scandal which I got faced and I have only once had chain suck and that was at the end of a long ride with a dry squeaky chain

    You used to be able to buy something called a sharksfin which stuck on the top of the chain stay and supposedly stopped the chain getting jammed between the rings and the stay havent seen one for a while but at one time they were the all the rage in the days when you could expect to be digging your chain out of your frame at least twice a ride
    Fig rolls: proof that god loves cyclists and that she wants us to do another lap
  • andyturner28andyturner28 Posts: 1,225
    stubs wrote:
    have you had the bottom bracket faced I have a on-one scandal which I got faced and I have only once had chain suck and that was at the end of a long ride with a dry squeaky chain

    You used to be able to buy something called a sharksfin which stuck on the top of the chain stay and supposedly stopped the chain getting jammed between the rings and the stay havent seen one for a while but at one time they were the all the rage in the days when you could expect to be digging your chain out of your frame at least twice a ride

    No i haven't had the bb faced, as a couple of people who have 456's said you don't really need to, as because it is steal it should be straight already. Also i was too impatient to get it built up :) Dose facing make that much difference?

    Just seen your sig stubs, and agree about the fig rolls, although all my local supermarkets have stopped selling them. Do you know who still sells them?
  • skylinerskyliner Posts: 613
    Your problem more than likely stems from the fact that you have a XT HTII middle ring fitted in conjunction with a std RF big ring.
    Allow me to elaborate- the HTII middle ring is spaced 0.6mm outboard as is the outer ring.
    When you use a combination of HTII and standard rings, the pickups on the big ring will snag the chain in the higher gears on the block. If your setup is particularly chainline sensitive it can foul in the mid range also.
    The cure is to fit a std spaced middle ring, or a HTII big ring. But never to mix the two different spacing patterns.
    It's nice to be important, but it's more important to be nice.
  • andyturner28andyturner28 Posts: 1,225
    Thanks Skyliner. Do you think i would be better off getting a RF middle ring, which i was planning to do anyway as well as the granny, so they all look the same, or just go back to an XT HT11 outer ring? Funds are a bit short at the mo and the middle is cheaper option :roll:
  • mr mangosmr mangos Posts: 174
    That's interesting Skyliner, but would it account for the chain jamming when it's on the big ring already?
  • stubsstubs Posts: 5,001
    stubs wrote:
    have you had the bottom bracket faced I have a on-one scandal which I got faced and I have only once had chain suck and that was at the end of a long ride with a dry squeaky chain

    You used to be able to buy something called a sharksfin which stuck on the top of the chain stay and supposedly stopped the chain getting jammed between the rings and the stay havent seen one for a while but at one time they were the all the rage in the days when you could expect to be digging your chain out of your frame at least twice a ride

    No i haven't had the bb faced, as a couple of people who have 456's said you don't really need to, as because it is steal it should be straight already. Also i was too impatient to get it built up :) Dose facing make that much difference?

    Just seen your sig stubs, and agree about the fig rolls, although all my local supermarkets have stopped selling them. Do you know who still sells them?

    I couldnt say that it would solve the problem but I have always had it done and I have only suffered chain suck on the odd occasion it might be an idea to have your LBS check if only to eliminate it my LBS does it for £10 I ring ahead and carry the bare frame down and they do it there and then takes about 5 minutes to do

    as for fig rolls your right supermarkets dont seem to stock them very often I buy mine from southport market which is not a lot of help for you but if you have a morrisons nearby they always seem to carry them
    Fig rolls: proof that god loves cyclists and that she wants us to do another lap
  • nicklousenicklouse Posts: 81,520 Lives Here
    there is a shortage of Figs at the moment.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • AnonymousAnonymous Posts: 79,692
    sounds to me like damaged teeth on the large chainring, or at the very least, the chain, and large chainring being worn to different degrees.

    Why did you change the outer chainring so soon after getting the bke? (2 months was it?)
  • andyturner28andyturner28 Posts: 1,225
    sounds to me like damaged teeth on the large chainring, or at the very least, the chain, and large chainring being worn to different degrees.

    Why did you change the outer chainring so soon after getting the bke? (2 months was it?)

    The chainset came off my old bike and it is well over a year old now. I went for a RF ring as everyone claims they last longer than Shimano, so thought i would give it a go. It looks better too :)

    There are no damaged teeth on the chainring. Had a good look yesterday, and i am quite surprised concidering the number of times i have got hung up on fallen trees. The chain is only about a week older than the outer ring, and was run with the worn Shimano outer ring for about a week. Could that have worn the chain out quicker? Oh and it seems to happen the most when i am already on the big ring.

    Andy.
  • AnonymousAnonymous Posts: 79,692
    there's definitely something going on with your big ring by the sounds of it. hmm.
    Have you checked that the chainring is straight?

    I managed to snap a middle chainring once, and it was almost impossible to see when the chanring wasn;t under load. All the teeth looked fine, and the ring looked fine, until it was under load, then it would open up where it had cracked.
  • stubsstubs Posts: 5,001
    nicklouse wrote:
    there is a shortage of Figs at the moment.

    Never mind the the economy going tits up what the hell am I going to do without fig rolls I have already cut back to 10mpfr (10 miles per fig roll) looks like I will have to stretch it to 12 mpfr :cry: why me god why me
    Fig rolls: proof that god loves cyclists and that she wants us to do another lap
  • AnonymousAnonymous Posts: 79,692
    mmmmmm fig rolls.
    I reckon my sister probably has them all.
  • stubsstubs Posts: 5,001
    I am off to panic buy some fig rolls should have room to store them next to the jerry cans full of diesel :)
    Fig rolls: proof that god loves cyclists and that she wants us to do another lap
  • andyturner28andyturner28 Posts: 1,225
    stubs wrote:
    I am off to panic buy some fig rolls should have room to store them next to the jerry cans full of diesel :)

    During the last fuel blockade my work filled a couple of 4 gallon cans and forgot about them. Well we decided to use them them yesterday, and bearing in mind the fuel is over 6 years old, it was quite nervewracking driving around today! I was sure Deisel went off after a couple of years.

    I couldn't find any fig rolls, so got Jaffa cakes instead, and i am now addicted to them. Got three boxes intending to save them for tomorrows ride, but i have eaten one already! Luckily they are only 1g of fat each!

    As far as i can tell the chainrings are streight. Had a chat in a really good bike shop in Rainham today and he thinks it might be because i mixed rings. Looks like i am buying a new XT ring soon then :roll:

    Cheers,

    Andy.
  • andyturner28andyturner28 Posts: 1,225
    Think i have found the problem, one of the chainring bolts was missing! I never thought of checking that, one of the guys i was riding with yesterday spotted it the first time he looked :roll: Oh well, been meaning to get some nice anodised blue bolts for a while :)

    Oh and Jaffa cakes don't make very good trail snacks! Were more like Jaffa crumbs by the time i got to eat them :x

    Andy.
  • stubsstubs Posts: 5,001
    Fig rolls 1 jaffa cakes 0

    there is only one thing that comes close to the fig roll in the heavyweight ride snack championship tescos light choices apple and raisin bars 99p for a box of 5 they are like a large fig roll and they are individually wrapped so they survived a 25 mile ride around pendle hill yesterday in pretty good nick couldnt find any fig rolls so I have bought 5 boxes to tide me over
    Fig rolls: proof that god loves cyclists and that she wants us to do another lap
  • andyturner28andyturner28 Posts: 1,225
    stubs wrote:
    Fig rolls 1 jaffa cakes 0

    there is only one thing that comes close to the fig roll in the heavyweight ride snack championship tescos light choices apple and raisin bars 99p for a box of 5 they are like a large fig roll and they are individually wrapped so they survived a 25 mile ride around pendle hill yesterday in pretty good nick couldnt find any fig rolls so I have bought 5 boxes to tide me over

    Yeah i had them on the South Downs Way ride in April. Think i will stick to them in future, although i tried some Powerbar bars yesterday which were very nice. Might take a combo for the next long ride.
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