[Closed] Chain devices - why are they so big?

adjustability.

Looking for something to stop your chain falling of on XC rides that's not big and ugly?

You need one of these http://wolftoothcomponents.com/ 🙂

jambo - explain

sss - touche

most of the size in both those devices is to account for frame differences, different chainring sizes, chainline issues etc.

i meant length front to back - not up/down

When a few other manufacturers start producing none droppy chainrings, chain devices will only be found where they belong.

On DH bikes. 🙂

Without a outside guide (the Hope has inner and above and relies on a bash for the outside) what will happen when you're hammering through a rock garden and the whole frame is twisting around the bottom bracket? I think you need a certain amount of clearance to cope with frame and drivetrain flex, and to avoid mud annoyance, and if you have that clearance then there'll be opportunities for the chain to jump unless its surrounded on all sides. I've just fitted the Hope seat tube mount one, along with a generic bash. Seems pretty neat...

And I suspect the front to back length is to accommodate the changing 3D chainline depending on the gear you're in and what your rear suspension is up to.

the gap would have to be nearly chain height for it to even think about jumping off. Frames flex that much, give over!! What is yours made form, spaghetti?

There's a part of me that tells me it's a fashion thing.

People want to make their bikes look like it's more gnar than it is.
And what better way to do it than with a chain device lookalike.

Chain can drop off either side of the chainring - shifting down or up the block will put sideways forces on the chain, so its possible for it to come off either side? Doesn't need to jump up to derail?

still doesn't answer why the cage is so big tho

Chain can drop off either side of the chainring

You seem to not understand how the Hope guide works.

Look at the top bit of the guide that stops the chain jumping [b]up[/b] and off the ring.

Though as i said before with a nonedroppy ring and a clutch mech you dont even need a Hope device for CX.

with the hope device how can it drop off the outside - the chain would need to come off the top of the teeth

When a few other manufacturers start producing none droppy chainrings, chain devices will only be found where they belong.

On DH bikes.

Will they heck, XX1 barely holds the chain anyway, and that's before it starts wearing the teeth.

I had the M-part version of the E-13, with an 11-34 cassette the chain only just cleared the top/bottom/left/right bits of the guide so in fact it's just the right size. The hope one isn't unique in it's design, until it became fashionable to ditch the bashguard they mostly worked like that apart from MRP who used a roller.

I reckon the advantage of a bigger cage is it stops the chain derailing further back on the chainring (i.e. where it's not completely engaged on the teeth) and requires less force to keep it on. Looking at that hope one it might be more prone to jamming if the chain comes half off?

The Hope device doesn't aim to work any differently to any other single ring chain guide and they all use bash rings or full plastic cages.

The Hope one is designed for use with a bash ring if you read the manufacturer's blurb, so there is probably a reason for this.

XX1 barely holds the chain anyway, and that's before it starts wearing the teeth.

Glad you've can afford to have worn an XX1 chainring out before most people can afford to even buy one. 😈

Re XX1- even some SRAM sponsored riders have declined to use it without a chain device. Doesn't really inspire confidence... Haven't tried it myself yet but will be getting an XX1-ish chainring soon to try.

chiefgrooveguru - Member

what will happen when you're hammering through a rock garden and the whole frame is twisting around the bottom bracket?

The frame can flex as much as it wants- the cranks and the BB shell and the chain device all move as one, provided it's a proper BB or ISCG mounted device.

The frame can flex as much as it wants- the cranks and the BB shell and the chain device all move as one, provided it's a proper BB or ISCG mounted device.

BB spindles, cranks and chainrings still flex, otherwise front mechs wouldn't rub.

My front mechs would still rub if there was no flex anywhere tbh! But yes you're right, there is minor flex elsewhere, just referring to the frame.

Haven't tried it myself yet but will be getting an XX1-ish chainring soon to try.

I've just fitted one to a new build.

I'm hope it works. But if it doesn't i'll just stick the E13 guide back on and pretend my bikes all gnar n ting. 😆

Yeah, I'm hopeful... I can see me making up a super-mini-tiny chainguide to back it up though. Sort of like clutch mechs mean I can mostly get rid of my bottom guides, maybe fancy rings will mean top guides can be minimalist if they're needed at all. Interesting, anyway.

I made a guide for the soda that was barely more than a bolt- idea was that it'd sit directly above the chainring with so little clearance that it didn't matter that it had no side guides, it couldn't go "over" the ring. And it very nearly worked, the only downside was that when it didn't work, it was completely impossible to put the chain back on without dismantling the guide

[img] [/img]

Somafunk posted this photo in a previous thread, I think the Hope guide would work without the bash but not 100% sure.

It looks much cleaner than other bulky guides

thats my thought

the only downside was that when it didn't work, it was completely impossible to put the chain back on without dismantling the guide

I remember having a bike with a square taper crank setup that used to drop the chain off the inside of the granny ring and get jammed between the inside of the crank and the frame.
I ended up taking a crank extracter out with me on most rides so if it happened i could pull the crank off the free the chain. 😯

I think the Hope guide would work without the bash but not 100% sure.

I think the guide arm would need to be positioned much further back for that to work.