SS Build - Help Needed - PLEASE

[gb155]

Having looked again at the video it could be an old (very stretched) chain on a new sprocket ? Combined with the sub-optimal chainline that will throw chain off like that.

My experience of fixed conversions is that, on the workstand, if everything else is right even a poor chainline won't throw the chain off the sprocket like that, so I think there may be something else to it as well as the chainline.

Chain is brand new

Sprocket however is far from new

 

[4F]

That's miles off Gaz (Chain line). Where have you put the front chain ring - If it's on the outside of the spider, move it to the inside.

If you can't then how much space is there between the chain ring and frame. Because, you may need another BB with a shorter Axel.

Eg. if the BB has a 120mm axel, you may need 110 or less.

What hub is on there -is that a standard 130mm ?

Correct chain line:-

chain's slack

 

[Rohloff_Brompton_Rider]

Chain is brand new

Sprocket however is far from new

problem solved. new sprocket needed and chainline needs sorting. however, sheldon brown reckons a multi speed chain (3/32") will allow a misalignment

 

[DrSquirrel]

Looking at how near the end it is in the drop outs - maybe an extra link is needed to shove it back a bit?

Double check that the space between the rear stays against the tyre left and right are exact.

 

[fossyant]

What hub is it. It looks like a road hub for a freewheel.

Has the wheel been built to ss with correct dishing ?

Do you have to squeeze the frame together to fit the wheel in the reop outs ? If there is space, you may have to add spacers to both sides - this will bring in the sprocket slightly.

Other option is to try and get a 3/32 freewheel, and run a standard 8 speed chain. Standard chains flex more laterally than a 1/8 chain

 

[gb155]

What hub is it. It looks like a road hub for a freewheel.

Has the wheel been built to ss with correct dishing ?

Do you have to squeeze the frame together to fit the wheel in the reop outs ? If there is space, you may have to add spacers to both sides - this will bring in the sprocket slightly.

Other option is to try and get a 3/32 freewheel, and run a standard 8 speed chain. Standard chains flex more laterally than a 1/8 chain

Ermmmmm I'm not sure tbh but I'll look tonight

What sprocket and from where would you knowledgable peeps suggest ?

 

[PpPete]

Ermmmmm I'm not sure tbh but I'll look tonight

What sprocket and from where would you knowledgable peeps suggest ?

If you are on a budget :
http://stores.ebay.co.uk/shacklewell-components
cheap & quick IME
don't know what the durability of his freewheels is like, but his fixed sprockets have always been fine for me.

 

[mickle]

Just to clarify - the chain jumping problem was caused by use of incompatible components; a narrow 3/16" chain on an 1/8th sprocket.

A slightly imperfect chain line may make a racket and cause premature transmission wear but it won't throw the chain.

Because, after all, multi-speed deraillieur systems rarely run with a perfect chain line.

nb. It is possible however to run an 1/8th chain on a 3/16" sprocket and/or chain ring.

 

[gb155]

If you are on a budget :
http://stores.ebay.c...well-components
cheap & quick IME
don't know what the durability of his freewheels is like, but his fixed sprockets have always been fine for me.

At that price I could get one of each :-)

 

[Red Light]

Chain is brand new

Sprocket however is far from new

That's your problem then. Just like on derailleur gears, a new chain on a worn sprocket will ride up and slip.

As for chainline you really should get your head round it because you ought to get it right on a derailleur geared bike as well. The chainline should be straight in the middle ring and middle of the rear block.

 

[gb155]

That's your problem then. Just like on derailleur gears, a new chain on a worn sprocket will ride up and slip.

As for chainline you really should get your head round it because you ought to get it right on a derailleur geared bike as well. The chainline should be straight in the middle ring and middle of the rear block.

What's a middle ring ? Lol :-)

 

[Red Light]

What's a middle ring ? Lol :-)

Sort of like Middle Earth* but more ringy.

* a place of epic struggles.

 

[fossyant]

What's a middle ring ? Lol :-)

It's something that girls have fitted to their bikes, or mucky MTB'ers !

 

[gb155]

It's something that girls have fitted to their bikes, or mucky MTB'ers !

I've heard of these things

Must investigate

 

[fossyant]

What a middle ring or a mucky MTB ?

Almost as bad as a compact !!! Shush - might have to get a compact if I want to carry on cycling in the hills, especially steep ones.