Hi.

I am wondering if its possible to use carbon fibre tube instead of steel or dural to make some motorcycle push rods (they are the things in an old fashioned engine that go between the camshaft and the rocker arm to open the valves when the cam turns). The original ones are 11mm o/d with a wall thickness of 1mm (steel) or 1.5mm dural and they are fitted with hardened end caps which are either soldered or bonded on. I was wondering if your 10mm o/d tube would be strong enough to use as a replacement as there should probably be quite a weight saving.  

Hi,

I don't think that in their standard form, carbon fibre tubes would be suitable for this sort of use. Composites like carbon fibre can be quite britle in an impact (particuarly repetative impact) situation and also the high operating temperature would not help either.

If they were engineered specifically for this task (high temperature resin system, consideration to fibre orientation etc) then there might be a possibility but using an off-the-shelf tube in this way would not be recommended.

Best regards, Matt

Matt Statham
Easy Composites / Carbon Mods - Technical Sales