Forum menu
Just a quick one...
When attempting to calculate the correct chainlength around the 36t rear sprocket and the 32t chainring the chain is not in mesh on the underside of the chainring as its meshing in wide-narrow. If i mesh it in correctly the chain now has sag in it.
Dumb question but is overall chain length assuming its meshed into the correct teeth on the chainring or meshed incorrectly with the minimal amount of sag.
If you get what I mean?
this question makes no sense!
I was about to give out to butlerjamesp for not being helpful but actually having read your post a few times it makes no sense to me either.
I don't know what you mean by mesh either. Can you try and explain again?
So I think what you're asking is: Do you
A) wrap the chain around the sprockets correctly and shorten it to an appropriate length in the biggest ring (allowing for some chain growth if it's a full sus), or
B) wrap the chain around the sprocket [b]in[/b]correctly and end up with a saggy chain without tension
If you can't work that out for yourself, I'm not sure we can help.
This may be a time when a picture not only says a thousand words, but also makes sense...
Don't forget you're putting a mech on too
You'll need to add four full links to whatever length you make it anyway (or two if you're on a hardtail) so a bit of slack is acceptable. If you don't 'mesh' it correctly you won't get the right length
[url= http://www.epicidiot.com/sports/chain_length_calculator.htm#results ]Epic Idiot[/url]
That rule of thumb is exactly that.. Someone stuck a thumb is the air and guessed.. rubbish.
It's all dependant on you frame and linkage. Vpp and dw links have a rearward path if I did the rule of thumb above I'd be stuck somewhere with a snapped chain.
I've had to go about mine differently.
Similar to this guy (if you can ignore his accent hehe)
[url=
Tips: Chain Length and Rear Derailleur Setup:[/url]
Excuse me all im talking utter bollocks and your right it makes no sense (long stressful day) 🙂
However the following does which I suspect is a mixture of mech / chainstay length compatibility.
The whole reason I asked is because I have chain tension problems when trying to adjust the b-tension screw properly.
I'm running the following:
Turner flux frame (air out of shock whilst setting up)
11-36t Cassette
32t Narrow wide chainring
Zee FR Short cage clutch mech
Ive got a situation that if the b-tension is adjusted so the jockey is correct on 36t my tension is mega slack on 11t
If I take a link out it'll probably rip the mech off in 36t when the shock is fully compressed.
I can get round it by adding a link back in but adjusting the b-tension so the jockey is about 12mm away on 36t
Seems to ride OK but what do you reckon, longer cage mech?
The Shimano short cage is very short and there's situations where the bike's chaingrowth is too much for it. You can't, frinstance, run a wide-ish ratio cassette on my 224 with it, it can't take up the slack, 11-28 seems to be about the limit. Before someone says it, no, it's nothing to do with the mode adjuster. I think a lot of people just assume "well it works for me, therefore it'll work for you", not true.
So yeah it is entirely possible you need a longer cage. You might also be OK going with a set-up that has the chain a bit tight in the lowest gears- you won't often bottom out the suspension in the 36T. But I really don't like that option personally.
I'm running the same drive train setup on a Blur and found the tolerances to be tiny it took me quite a while to find the balance of chain length and B-screw, but it seems fine now and runs sweet as a nut.
If you end up grabbing a hope t-rex in the future you may well need a long mech...im currently investigating all this myself.
The FR zee is only just enough for 11:34 on my hardtail. I know some people have managed bigger ranges but unless their mech is different I don't understand how they've done that.