Chain resting/rubbing on front derailleur

jimmyjones

Hi there, so decided to build my own bike and everything was going swimmingly apart from a few hiccups with the drivetrain.

Frame: Kona Coiler 2005/2005
Front Derailleur: Shimano Deore
Cranks: Truvativ Firex (3 rings, top ring 44teeth)


Only seems to rub when on the smallest cog on the front which considerably changes the path of the chain.

Took it into a bike shop and they only thing they could suggest is that I hadn't bought a 44teeth compatible derailleur, so after buying a new Shimano Deore XT (top clamp, 44-48 teeth compatible) I still have the same problem and am mistified.

Dont have a pic but if needed could post a snap.

Any help ideas would be great thanks

nicklouse

What fitting cranks?

What axel length if not GXP fitting?

jimmyjones

nicklouse wrote:

What fitting cranks?

What axel length if not GXP fitting?

It is GXP, the crank run through a shimano hollotech externl bracket

nicklouse

jimmyjones wrote:

nicklouse wrote:

What fitting cranks?

What axel length if not GXP fitting?

It is GXP, the crank run through a shimano hollotech externl bracket

No you don't, they do not work together unless you have made up a reducer to make them work.

So what have you got! How have you got the spacers between the frame and the BB cups?

The BB is a ....... Make and model?

How many spacers drive side?
How many spacers non drive side?

jimmyjones

nicklouse wrote:

jimmyjones wrote:

nicklouse wrote:

What fitting cranks?

What axel length if not GXP fitting?

It is GXP, the crank run through a shimano hollotech externl bracket

No you don't, they do not work together unless you have made up a reducer to make them work.

So what have you got! How have you got the spacers between the frame and the BB cups?

The BB is a ....... Make and model?

How many spacers drive side?
How many spacers non drive side?

The bottom bracket is a SM-BB70.

I'vwe got 2 spacers on the driver side and one on the other. I have also had to put a spacer between the bracket and the crank on the non drive side as there was around 5mm of space.

However the chain is resting on the derailleur at the bottom and not hitting the sides.

Is my setup all together wrong you think?

nicklouse

Ok I read what you have written. The reducer you made to get the Firex cranks to work with the shimano cups is I a one piece top hat or a two piece?

And what are the thickness of the rim parts?

jimmyjones

nicklouse wrote:

Ok I read what you have written. The reducer you made to get the Firex cranks to work with the shimano cups is I a one piece top hat or a two piece?

And what are the thickness of the rim parts?

The spacer I've used is a single spacer, originally for a steerer tube think. about 5-10mm wide and 2 mm thick.

Also the spacers between the BB and frame are all 2.5mm spacers, if thats what you mean by rim parts? Sorry not clued up on all part terms

nicklouse

jimmyjones wrote:

nicklouse wrote:

Ok I read what you have written. The reducer you made to get the Firex cranks to work with the shimano cups is I a one piece top hat or a two piece?

And what are the thickness of the rim parts?

The spacer I've used is a single spacer, originally for a steerer tube think. about 5-10mm wide and 2 mm thick.

Also the spacers between the BB and frame are all 2.5mm spacers, if thats what you mean by rim parts? Sorry not clued up on all part terms

Just go and buy a GXP BB and fit it up with one spacer each side.

As nothing you have written can I see as working as you have nothing the put in the Non drive side cup to make the axle fit correctly.

Or strip it all down a post up a picture so we can see what you are doing.

jimmyjones

Okay thanks I will! I assume any will work GXP will work? or do I need a specific type?

thanks

nicklouse

If it is GXP compaible it will work. If it is Shimano I will not.

Some can be bought with reducers to allow it to work with either.

I am surprised that the cranks are not wobbling all over the place.