® Why I don't include new fuel hose on rebuilds

This is the Japanese-made, dual-layer, high quality fuel hose that was original equipment on vintage Hondas. See the faint red stripe? It is still available, at a price, and not from Honda.

Some have asked why I don't fit new fuel hose to the carburetors I rebuild. There are reasons, and the situation is not a simple one, so some explaining is necessary.

Fuel hose for motorcycles is one of the harder things to deal with when rebuilding carburetors. There just isn't an easy way to handle it. Here are some of the reasons. First, very few fuel hose choices are sized correctly. All of Honda's fuel fittings are metric, and 90 percent of the available fuel hose is not. This may seem a small issue, but it really isn't. There is a pretty big difference between 5mm and 1/4", for example.

Next, Honda often annoyingly puts differently-sized fuel fittings on a given carburetor/petcock combination, so one end of the hose has to fit one size while the opposite end is forced to stretch to a larger size. Strange, this, but there it is. And quality fuel hose that can fit properly on two different fuel fittings is not real common. You can believe that.

Third, quality. Hondas came from the factory with dual-layer fuel hose. Incredibly good stuff, the outer layer was hypalon, the same thing that covers spark plug wire. The inner was Viton, high quality. This dual layer hose was so good it resisted decay for over 30 years, what with the outer layer standing up to the ravages of the sun many times better than any other hose. So good in fact that I would rather leave still-intact but hardened OEM fuel hose on the carbs rather than replace it with anything I can find that is going to inevitably be inferior hose.

Fourth, though Honda makes "factory" hose available, it is not this original stuff. Fair hose, but not the same as that used in the 1970s and 1980s. Interestingly, a Japanese importer does offer the original Honda red-stripe dual-layer hose. It is indeed available, even in the tiny overflow hose sizes. Just not from Honda. But it is breathtakingly expensive. So, just put the Honda red-stripe hose on, problem solved. Well, that would be fine except the cost is prohibitive for me to include it in the rebuild, and few customers will pay the extra freight for this good hose. I haven't sold any red-stripe in a couple years.

Fifth, quality, again. Motion Pro and just about everything out there, even the Geman-made Continental brand cloth outer braided stuff, is poor quality. I won't use it. Motion Pro is the same as most offerings: ozone-vulnerable, quickly-hardening, thin-walled (and loosely fitting) Tygon (i.e., plastic), and the Continental hose, well, underneath the fancy braiding is actually very low-grade almost natural rubber, the poorest hose material choice on the planet and thus so unreliable it is actually responsible for early VW cars catching on fire. And what about auto parts store hose? Except in the 1/4" size, which occasionally can be purchased in a form snug enough to substitue for Honda's 5mm original, most parts store stuff is off, size-wise. It also tends to be poor quality hose that tends to chunk internally, resulting in obstruction and other others in the fuel system. One thing I will say for most car hose though, at least it is designed to resist kinking.

Sixth and last, and perhaps the hurdle that remains even after the other issues are solved, is this. With various petcock and carb and fuel filter combinations and configurations, I have found it is best to let the customer make his own fuel hose arrangement. If I try to anticipate things, all I am doing is wasting product because lengths and curve radii and inline filter choices are all variables. It's best if I stay out of it, though sometimes I send back with the carbs a cut-off length of hose for the customer to fit as he chooses.

So there you have it. The challenges of supplying my customers with new fuel hose. The choices run the gamut, the customer's expecations and configurations do also, and the marketplace is geared toward cheap. And I don't do cheap.

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