Top vs. bottom pull derailleur

X

xfromx

Squid
Hi guys. I'm a bit confused about the difference between top pull and bottom pull front derailleurs. I've just bought a new frame and not sure which one i need. The cable comes down from the top tube, so i'm assuming i need a top pull, is this correct? Also i read something that one kind can operate as both (i'm assuming this might be the bottom pull type).

Any help is greatly appreciated. Thanks all, xfromx.
 
Ryan Hotdog

Ryan Hotdog

Likes Dirt
Your frame design bears no consequence on what derailleur to get. Top and Bottom pull refer to which way the derailleur moves when cable is released from the shifter. You have to make the descision which way you want the gears to go when the release leaver is pushed/pulled.
 
L

le chat

Likes Dirt
Ryan Hotdog said:
Your frame design bears no consequence on what derailleur to get.
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Depends on where the cable stops are located.

Have a look at where the cable routes from the front mech. If it comes down, and routes under the BB shell and along the downtube you're likely to have a bottom pull. If it routes from the top, up seat post and along top tube you're likely to have a top pull.
 
Ryan Hotdog

Ryan Hotdog

Likes Dirt
le chat said:
Depends on where the cable stops are located.

Have a look at where the cable routes from the front mech. If it comes down, and routes under the BB shell and along the downtube you're likely to have a bottom pull. If it routes from the top, up seat post and along top tube you're likely to have a top pull.
Click to expand...
Are we talking about a front or rear mech here? I was thinking rear?
 
AngoXC

AngoXC

Wheel size expert
Ryan Hotdog said:
Your frame design bears no consequence on what derailleur to get.
Click to expand...
Ill play. Frame has EVERYTHING to do with what sort of derailleur to get. le chat is correct in pointing out that the cable stops will determine what pull derailleur to get but such things as suspention and clearance will determine the type of clamp/swing. Some frames may not even provide a down tube for a front derailleur in which case you look into e-Type derailleurs which mount to the BB.

A top swing, as the name suggests, pivots down from the top...it is clamped high and is typical of road bikes. A bottom swing, is mounted closer to the BB and is more common on MTBs where clearance is an issue.
 
RaID

RaID

Likes Bikes and Dirt
Ryan Hotdog said:
Your frame design bears no consequence on what derailleur to get. Top and Bottom pull refer to which way the derailleur moves when cable is released from the shifter. You have to make the descision which way you want the gears to go when the release leaver is pushed/pulled.
Click to expand...
Thats not right. it refers to where the pulling force of the cable is applied to the derailleur so that it moves outwards, ie from the top or bottom. It actually it depends on where the cable stops are on the frame to which type of derailleur you need.

xfromx sound like you need a top pull since your cable comes from the top tube down the seat tube to the derialleur, this means it will be pulling from the top.
Like you said there are some models that can do both top and bottom pull.
 
BM Epic

BM Epic

Eats Squid
Ryan Hotdog said:
Your frame design bears no consequence on what derailleur to get. Top and Bottom pull refer to which way the derailleur moves when cable is released from the shifter. You have to make the descision which way you want the gears to go when the release leaver is pushed/pulled.
Click to expand...
Your thinking top normal and low normal(rapid rise),i think he is talking about front derailleur,i do know what you are saying though!:)
 
X

xfromx

Squid
Ok.
It's a hardtail (on-one inbred) and the cable goes along the toptube and and down the seat tube. I figure i'll need a bottom swing, but with a top pull type arangement.
What do you fellas reckon?
Thanks for all the replies!!!
xfromx
 
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