Issue with single ring conversion

[felts bend]

I have just installed a single front ring on my bike with chainguide. Now i'm having the issue if i back pedal even the slightest my chain will come off the inside of the front ring I have noticed when i back pedal the deraileur seems to be catching and it pulls forward as i back pedal.
What would be causing this as it never did this before.
And before people tell me not to pedal backwards sometimes on DH theres not enough time to put another forward rotation in before the cranks are needed flat again and also for DJ's i need to get my pedals right from the top of the run up
Cheers.

 

[cluster]

sounds like you just need to reallign your derailleur (either at the barrel adjust on your shifter, or on the derailleur itself - depending on what brand drivetrain you're using)...
or perhaps there's a stiff link or two in the chain... but the above is more likely.
also what chainguide are you using and have you spaced it correctly so that it is lined up with the middle of the cassette (most used gears)?
anyway good luck.

 

[maxwolfie]

What guide is it? Does it have a idler/jockey/whatever-you-want-to-call-it wheel?

 

[muskimo]

another slight possibility is where you have your front ring bolted. is it on the inside or out side of the 4bolt spider? if its on the out side that may be the cause of it pulling off the ring as its too far off line? maybe?

 

[felts bend]

its an fsa chain pimp and it has 2 rollers top and bottom, and its on the middle ring, i'm going to check the deraileur later as i have readjusted it, but the gear indexing is perfect so i don't know if it'll be that. Could it be from excess slack in the chain?

 

[muskimo]

i doubt it would be the excess slack, as the derailleur will pick up any slack and make it firm

 

[AngoXC]

Chain line could be a distinct possibility.

How old is the chain/front ring? Uneven wear or any damage might be another factor.

Is the front ring a specific single ring or is it one that has been designed for use with three rings? (ie. features ramps to assist 'derailling' the chain)

 

[felts bend]

chain guides brand new, i just realised what it is when i roll the cranks backwards the chain ramps up the bevel on the bottom roller throwing the chain off, so im going to change it to a flat roller