Forum menu
[url= http://www.singletrackworld.com/forum/topic/rusty-chainstays-how-much-is-too-much ]As referenced in a previous post[/url], I've been having problems with chainsuck. It bit me big time today as I was in the park with my nephew, he's 6 and I'm teaching him how to ride. He absolutely [b][i]loves[/i][/b] watching Danny MacAskill and the like, so I was showing off and jumping over a small ridge. The first couple of attempt went well, so on the third I thought I'd take a longer run up to a steeper take-off. Unfortunately as I put the power down, the back wheel locked solid and I was pitched forward. I hung on for grim death as I went over the front, convinced if I kept off the brakes and moved back enough, I could rescue it - but it was not to be. Momentum was too much and in what seemed like slow motion (and in ful view of everyone in the park) I went ignominiously over the bars, still clipped into my SPDs.
As this is the fourth or fifth time the wheel has locked up in the last couple of rides I got a bit peeved and turned the bike upside down to take a good look at the chainset. Before I could do so though, something else caught my eye - it turns out I've been looking in the wrong place
[URL= http://img33.imageshack.us/img33/3859/rimg0080x.th.jp g" target="_blank">
http://img33.imageshack.us/img33/3859/rimg0080x.th.jp g"/> [/IMG][/URL]
Now, I know pictures aren't always easy to make out, but I reckon even from that picture it's obvious that the wheel is nowhere near centralised. Looks like when I bent the gear hanger in a crash last year (rear meach was pointing upwards!), the dropout got splayed and the wheel has been running at an angle ever since. The splay has probably been getting worse and worse with the repeated strain, I'm not the smoothest of riders.
Bummer, anyone know if I can get it repaired for a reasonable cost? Either bent back into shape or chopped and replaced? it's an 835 inbred, so not something I'd want to throw away if I don't have to.
looks to me like the non-drive side chain stay is bent as well, there looks like two bend, one at the black mark and another a couple of cm down
Can't you bend it back into shape? I had a similar problem last year, also on an 853 inbred, and the dropout got badly splayed. Using an old axle screwed into the rear mech hanger I managed to bend it pretty much back into shape and its been fine since. Probably worth a try before having a new dropout welded.
the dropout got splayed and the wheel has been running at an angle ever since. The splay has probably been getting worse and worse with the repeated strain, I'm not the smoothest of riders.
Nope. Either your wheel is out of dish (badly) or the wheel has slipped in the dropout (horizontal dropout only) or the dropout has moved (sliding dropout only)...or below:
Does look like NDS stay is bent. It's possible that this has mis-aligned the dropouts.
None of the above will be causing chainsuck. No offence but if you think a damaged dropout (if vertical) causes chainsuck then I'd give up on self diagnosis.
Looks to me from the pic that the BB is no longer perpendicular to the axis of the bike, but hard to tell from the one pic. If you have a long and snug fitting hex key in the crank bolt you might be able to tell better, but if it were, it would certainly be a candidate for helping chainsuck along, as well as pondering a new frame. 🙁
all looks a bit odd back there - maybe more than 1 thing going on
IF your chainstays are pushed over to the driveside (as it looks, a bit) then the rings may be closer to stay than normal & may worsen effects of chainsuck. Does look like wheel or dropout has slipped as well though.
Get wheel out & check alignment of the back end with a bit of string tied to each dropout & then to BB. Angles should be more obvious.
You've been riding round on that and not noticed anything felt wrong.
I'd give up if I were you. 😉
Good grief. Looks like it has rear-wheel steering! 😉
mate, the back end of your frame is completely ****ed. it looks like someone's driven into the back of you in a car - the non drive side is all over the place! i'm surprised your heels get past it...
cheers for the feedback lads. I'm not an engineer so I'm not offended at being told I'm wrong, but it has made be pop out and check: the dish on the wheel is spot on, and there's no splay at all in the dropouts. It's vertical dropoutss so it's not wheel or dropout slippage either
there's definitely something wrong with the NDS chainstay, you can see where the paint has cracked, it's about an inch behind the black mark visible in the pics above
[URL= http://img14.imageshack.us/img14/7373/rimg0081.th.jp g" target="_blank">
http://img14.imageshack.us/img14/7373/rimg0081.th.jp g"/> [/IMG][/URL]
here's a pic of the back end with no wheel in
[URL= http://img30.imageshack.us/img30/345/rimg0091.th.jp g" target="_blank">
http://img30.imageshack.us/img30/345/rimg0091.th.jp g"/> [/IMG][/URL]
I'll see if I can dig a piece of string out and take nother pic
You've been riding round on that and not noticed anything felt wrong.I'd give up if I were you.
At times like this, I'm giving it serious consideration. bikes are sometimes more hassle than I care to deal with 🙁
At times like this, I'm giving it serious consideration
Nah. Just keep going.
Things can only get betterer. 😉
If you ride in with no hands, i bet money it would go round in a perfect circle 😀
it could just be the angle you've taken it, but in the upside down no wheel pic, the front half of the frame all looks lined up. the back half looks... totally unlined up. that frame needs either some serious repair work or binning.
WOW. You have properly whacked it!
Probably a bin job sadly 🙁
it could just be the angle you've taken it, but in the upside down no wheel pic, the front half of the frame all looks lined up. the back half looks... totally unlined up. that frame needs either some serious repair work or binning.
Looks like that to my eye too, not just in a photo. I'm left wondering what the hell has happened to it? Not been in any major crashes that I recall, the accident with the gear hanger was september last year and the chainsuck has not been happening for that long. maybe it's my hamfisted loading of bikes into the car, but I suspect it would take a lot of weight or a serious impact to do that kind of damage?
I suspect it would take a lot of weight or a serious impact to do that kind of damage?
AFAIK, tes.
run string from each dropout to the head tube and measure the gap to the seat tube.
Are they the same?
run string from each dropout to the head tube and measure the gap to the seat tube.Are they the same?
String duly run. Nope. Rough measurements are 34mm on NDS, 42mm drive side.
I'm hitting the beer.
I'd do as cynic-al says, run the string around the drop outs and then measure everything up.
Here's Sheldon Browns way of doing it
[url] http://www.sheldonbrown.com/frame-spacing.html [/url]
Ok too slow, but he does at least tell you how to straighten it all out, isn't steel great?
well, I ran the string like SHeldon, but I measured to the nearest point of the seat tube rather than to front centre
Sadly that thing's as bent as a bananna. However, the nice new blue 456s are only £125.... so happy days.....OOOR you could have a shiny new Ti456 and some free forks? happier days maybe?
😕 😳 👿 🙂
as pepper suggests, go to sheldons site and read up on cold setting.
and gently gently catchy monkey get that back triangle lined up again.
The frame will take it if youre careful.
although if there's a crease in the chainstay it may be beyond saving.
although god knows how you did it in the first place?
Have you got a fat sister who sat on it or something?
If it's been on a rear mounted bike rack I'd have said it's been either caught on something or gently driven into by someone else.
nbt - half price Blue Pig if you want one. Mail me.
Look at that, what an offer!
[Salutes the genius of guerilla marketing] It's like watching Armstrong race. You forget how good he was, and then you see him doing it again. 😀
Yeah, blue pigs come with ready-bent stays!
Now that's a stunning offer!
Now that's a stunning offer!
Well, it's still more than a full price on-one, but hey, the offer stands 😉
CHeers Brant, might be taking you up on that.
there's definitely a crease in the NDS, but will try the cold-setting as per Sheldon.
I've had a restless night's sleep as all I could think of was how the hell I did it. Despite my claims to a lack of mechanical aptitude, I do look a the bikes every so often and I'm sure I would have noticed something like that - so maybe it happened in the stack I mentioned in the first post. Thinking back, the bike was pretty much vertical when I toppled, and I landed on the NDS, still clipped in.