4mm vs 5mm Derailleur housing
Any opinions about using 4mm or 5mm derailleur housing? How about chrome vs Plastic end caps?
My Fuel 90 came with 5mm derailleur housing and chrome end caps. My local bike shop replaced these with 4mm housing with plastic end caps. Are these truly interchangeable? Which one is best?
Also, where can I buy rolls of housing and derailleur cables at a reasonable cost. I'm goint to start replaceing cables myself.
www.aebike.com is one good place to get Jagwire cables in bulk.
I'm not very smart on the differences, and have wondered that question myself, but haven't had much luck finding answers on what's different between 4mm and 5mm designs.
My opinion is that 4 vs 5 is a matter of preference and what fits better on your specific bike & its cable guides. Both diameters should work fine with most derailluer and shifter cable access points. I've heard that the inner diameter is the same on both, but who knows. By comparison, brake cables are 5mm, so I don't really know why derailluer housing comes in 4, 4.5, and 5mm options.
As far as ferrulles, metal is generally better than plastic. AEbike also sells a good selection of Jagwire ferrule designs that fit their varying cable diameters.
Use a Dremel to cut the housings - here's a great tutorial from Speedub.Nate.
The 4mm housings are better for the areas that need to flex a lot, like the shifter/frame section and the section that runs frame to swingarm on a FS frame and the final loop to the rear derailleur. The Jagwire 4mm housing is still not quite as flexible as the Shimano 4mm. That shiny plastic covering seems stiffer.
In the Shimano shifter kits the really small diameter cable housing is actually 3.8mm diameter, so is even more flexible, but that housing seems impossible to find except in their complete kits.
The Shimano and Park cable housing shears can do a neat job of trimming derailleur housing but they can still leave a mangled loop on brake cable casings that need cleaning up to get them squared off and free of additional cable friction
The 4mm housings are fine.....
that's all we use at the shop that I work at for derailleur cable runs. They are more flexible than 5mm housing, and the keep drit and crud out a bit better. However, the plastic end caps SUCK!!!! Derailleur housing consists of a low friction nylon liner that the cable slides through, wraped by small diameter twisted wire cables, and then a tough outer coating. The wires between the outer shell and the liner can and do move a bit. I've seen the wire stiffeners push right through the end of the plastic ferrules in as little as a couple of months or regular riding. We don't use the brass ferrules either as the exit holes often deform and can cause interference with cable movement over time. We use either Jagwire steel ferrules, or aluminum ferrules (can't remember the brand name on the alu ones), but both perform better and last much longer than the plastic. Plastic ferrules are fine if you keep an eye on them and replace your cables at least once a season or as needed. They are cheaper of course, but in this case you get what you pay for. I've got a set of the aluminum ferrules that we use at the shop that have been used 3 seasons and three sets of housing so far. The plastic ones that came on my bike stock lasted about 6 months before the wires in the derailleur housing pushed through them. It's not as big an issue with brake housing, as the stiffener wrap is actually flattened steel that is wraped around the liner and then covered, it doesn't shift or move.
Anyway, your choice, but next time I'd do either steel or alumimum ferrules on the ends of that housing.
"I do whatever my Rice Cripsies tell me to!"