Help!!!

westonpark

Hi all,

I'm in need of some help.

I've just had a strip down service to find that someone has filled the down tube with expanding foam, to stop any rattling (I guess)

However its improssbile to change the cables out since they are all stuck in the foam!

Any idea on how to dissolve or remove the foam?

Thanks

Long_Time_Lurker

When you say filled, is it the whole tube or just a small section?
I used to use foam cleaner when installing UPVC windows - but it was never inside anything.
You can buy Everbuild Foam Eater, but that is a paste so may not work inside a tube.
Other option is something like Tytan Foam remover which is a spray.
But both need you to be able to access the foam/tube and do some scraping.

Alejandrosdog

ok here is a solution

your cables are either in an outer or not
attach your internal cable routing tool (the park tool one or similar) to the existing cable
remove the existing cable and pull through the cable routing tool
discard the original cable but leave the cable routing tool hanging out both ends
attach new cable and pull through.

use the existing cable outers if your bike has them.

there must be a route through the foam because the cables need to move.

If youve pulled the cables out without attaching them to a internal cable routing tool then prepare for some fiddling and tears. irrespective, if theres a channel sufficient for the cable to move and actuate the gears then theres a channel you can feed the cable through. Again the tool might help and failing that a very strong magnet and some patience.

eric_draven

Long Time Lurker wrote:

When you say filled, is it the whole tube or just a small section?
I used to use foam cleaner when installing UPVC windows - but it was never inside anything.
You can buy Everbuild Foam Eater, but that is a paste so may not work inside a tube.
Other option is something like Tytan Foam remover which is a spray.
But both need you to be able to access the foam/tube and do some scraping.

The Everbuild Foam Eater could that be watered down a bit,if it could maybe try getting some in the downtube via the head tube or the bb shell
Westonpark I don't envy you on this job

tom_howard

Westonpark wrote:

Hi all,

I'm in need of some help.

I've just had a strip down service to find that someone has filled the down tube with expanding foam, to stop any rattling (I guess)

However its improssbile to change the cables out since they are all stuck in the foam!

Any idea on how to dissolve or remove the foam?

Thanks

As good a reason as any to upgrade to SRAM AXS?

larkim

Alejandrosdog wrote:

ok here is a solution

your cables are either in an outer or not
attach your internal cable routing tool (the park tool one or similar) to the existing cable
remove the existing cable and pull through the cable routing tool
discard the original cable but leave the cable routing tool hanging out both ends
attach new cable and pull through.

I suspect the problem here would be that the exp foam will not allow the cable outers etc to be pulled through at all - it's sticky stuff and may not move even with some serious brute force. If it was as simple as passing a new outer or inner through a hole in some exp foam I don't think there would be a plea for help!!

westonpark

Thanks guys.

The whole frame isn't filled. It's as if somebody has just sprays some thorough the head tube. However it's basically welded the cables together!

Ive managed to free three out of four cables, however the one that is still stuck is the rear brake cable and that needs sorting since the brake doesn't work. Fingers crossed its just a new lever or piston rather than the cable, otherwise its foam eater or external routing.

I cant afford an new frame!

westonpark

Will the foam eater damage the carbon frame??