maybe its the pressure your running but i see no reason a cap will stop that. the cap doesnt put any pressure on the valve core its self, all it does is keep stuff out of the schrader so you dont push crap into the bump or resi when you fill them. it adds no support to that pin or valve.Without the secondary cap in place you do risk blowing the needle out like i did. However i doubt it would be an issue for this guys use. When i blew mine out i had over 300psi in the bumps
That is highly inaccurate for this application, however that does five a baseline. That is only considering the nitrogen pressure and excluding the force created by the shims/valving.It could reach an infinite pressure, that's called hydrolocking and usually it just rips the bump apart. On my 4in stroke bumps I fill to the top and pull 10cc out when it's collapsed all the way. Mine are an old design with a mix of parts in them so the standard 175cc fill doesn't work so well. Boyles Law says that P1*V1=P2*V2. P1 is typically 200psi, V2 is the 10cc that I take out when fully collapsed, V1 would be the displaced volume of a 1.25 rod stroked 4in, converted to metric to make it easy which , plus the 10cc I leave out at the end which equals 79.2cc. Plug them into the equation, solcve for P2, ignore any influence from thermal expansion and assume your oil has no air emulsified into it, my bumps only reach 1784 PSI. Solving again for only taking out 5cc of oil, the result is 3568cc which is where you would get a bit nervous using 3kpsi working hose. Math, good for something.