® The ignition coil relay mod

One of the most common recommendations on forums is the ignition coil relay mod. Like virtually everything else on the 'net however, the effectiveness of this modification is way over-valued. Putting a relay into the ignition circuit, can indeed be effective. I did it for the first time maybe 40 years ago. Probably the most significant of Kettering ignition's weaknesses is that it is a voltage hog. The more you can get into it, the better it will work. This is how adjustments in dwell came about, for example. So theoretically at least, the mod can't hurt and really only help.

That said however, there are three things to be said against it, One, doing this mod ignores the real issue, the buildup of resistance in the wiring harness, which needs to be attended to regardless. 1970s and 1980s Hondas all suffer from wiring issues that the wiring harness manufacturers themselves caused. There are in fact five areas in every vintage Honda wiring harness that need special attention. Two, it is not guaranteed the relay mod will offer any advantage over properly maintaining the wiring harness. It is typical of forums to blindly emphasize the wrong things. Instead of modification, do the friggen maintenance! And, three, installing the ubiquitous Bosch style relay never seems to be done with any class. I have removed many in recent years. They sometimes present more problems than they fix, so poor is their installation.

Why can't vintage bike owners spend their energies on the things that really count? Careful engine tuning, proper clutch adjustment, avoiding Chinese replacement parts, and discovering and exercising factory assembly and adjustment ethic. So many are looking to get one up on the manufacturer and instead doing things that are worse than the manufacturer would ever have done. That's not high performance thinking but low performance.


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