Inlet manifold bushing clearance issue

[exeric]

H-D, Indian, and many other motorcycle companies used brass seals for the whole run of plumber type manifolds and it worked very well. The problems came later on with poor maintenance and improper installations. PEEK seals make this debate rather academic. Enfield Racing's PEEK seals solved all of my manifold problems. . . I just wish they had something that miraculous to fix magnetos.

[billpedalino]

My money's on Cotten as well.

[T. Cotten]

Kurt!

It seems like a nipple that is flush to the cylinder head should not egg on the rivet, but mild steel moves, especially with a cheater bar. And the overtorque syndrome applies to loosening as well.

But with seals, brass or PEEK, that are properly fitted to pristine spigots, extreme torque should not be necessary.

Many folks around the world have been cutting PEEK for this application for a decade now, and besides imprinting of blemishes, the only complaint voiced by other producers is that they loosen easily.

My seals that are cut to a tight fit upon the spigot require a re-torque of course, but loosening has never been reported as an issue.

Leak-testing while installing the assembly is always prudent. If spigots are of different size, but the seals are the same, then obviously one will require more torque. My contention is that the seal forced into compliance is most likely to loosen.

Let us know how it goes!

...Cotten