Rear mech and gears

RyanMK43

every time i push my bike backwards my rear mech jumps up a few gears. then when i spin the crank around it jumps back to the gear i was originaly in. im just wondering what is causing this or how i can sort it out. thanks

cooldad

You can't, it's normal. Bikes don't have reverse gears.

bamba

"im just wondering what is causing this", pushing your bike backwards.

"how i can sort it out", dont do it

cougie

Sounds like your mech is slightly out ? If its spot on - then it shouldnt do this.

But if its causing no bother forwards - dont mess with it.

And yeah - dont push the bike backwards. Do you have much call for this ?

ride_whenever

cougie wrote:

Sounds like your mech is slightly out ? If its spot on - then it shouldnt do this.

But if its causing no bother forwards - dont mess with it.

And yeah - dont push the bike backwards. Do you have much call for this ?

click me

It's just due to chain line issues and the drivetrain being designed to run in one direction, not a lot you can do other than leave the bike in such a gear that the chain runs straight.

d3matt

I would agree with cougie. If the rear derailleur is perfectly in-line, then the chain shouldn't shift a few gears. When setting up my rear mech, I turn it backwards to check the alignment and if the chain shifts cog, to me that highlights the alignment could be better and after a slight adjustment it doesn't.

RyanMK43

ok thanks. i only push it back when im putting my bike away in the shed. but as long as the rear mech isn't knackered im not worried about it

ride_whenever

d3matt, think about it. If the chain is coming into the block at an angle then when the drivetrain goes backwards it will naturally move down the block.

Try it, stick your chain in the big ring and towards the biggest on the block, then pedal it back. It almost certainly will run down the cassette.

d3matt

Yes you're right. I stand corrected and will correct my setup technique.

TuckerUK

d3matt wrote:

Yes you're right. I stand corrected and will correct my setup technique.

Whoa, hang on there buddy! You do realise this is an internet forum right? I think you'll find internet forum protocol is to ignore any information that provably discredits yours, and carry on promoting your disproved method regardless!

Newbies, sheesh. :roll:

d3matt

Yes you're right too!
I'm wrong again. Ahhh.