Part Four

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Wow, really on a roll this morning! More maintenance reports now.

I never touched the original ND spark plugs until about 45,000 miles, when I started have hot-starting problems. It finally dawned on me that the spark plugs probably had worn gaps and when the engine cranked, and the voltage dropped to 10 V or so, there was not enough spark energy to jump the wide gaps.

So out with the plugs and sure enough, they had gaps around .045" instead of the standard .025". I put in a fresh set of NGKs(using the plugs called out in the Kaw Manual, naturally) and presto, no more starting problem hot or cold.

Fine, everything working again, for about 20K miles, when the same symptoms reappeared. Out with the NGKs, and now they showed gaps around .038". This time I just re-set the gaps to .025" and the same plugs made it up to the 87K miles at which I changed the engine. I concluded from this that (a) NGK plugs wore their gaps faster than ND, and (b)they mis-fired at smaller gaps than the NDs, perhaps because of having a different resistor value built into them. It is not for me to know the reason, of course, but just based on this I would prefer the ND plugs to the NGKs.

When I got the bike in '91 I decided to take some unnecessary weight off it since I ride solo only(my wife does not care to ride it with me). So I fitted a two-into one exhaust system, which is getting a bit rusty, but still intact to date.

I did not touch the carburetors, deciding that no jet changes were necessary, and on neither the '88 nor the '01 engines did I ever yet touch the carburetors. They always worked just fine. In Virginia we have a saying, "If it ain't broke, don't fix it." It saddens me to see so many people telling stories about having trouble with their carburetors after they have tampered with them to fit "jet kits" etc. Evidently these carbs don't like being fiddled with, so I don't.

Anyway, I took maybe ten or 15 lbs. of weight off the bike by the exhaust system change, deleting the stock mirrors(replaced with a bar-end), center-stand, and rear footrests. This 'may' have made a perceptible difference in the feel of the bike but it could only be beneficial. The light weight of the bike is one of its main charms.

I admit that the exhaust note of the bike with the pipe on it is somewhat irritating to the rider, and probably to others. But I am of the school that thinks it is better to irritate fellow motorists into knowing you are there, than to fail to 'get to be an old man' because of the 'whispering death' of a stock exhaust. Besides, cultural norms have to be considered, and here in Virginia, for 100 years the public has expected motorcycles to be noisy, so people don't really mind it.

Whilst on the subject of safety, I might mention that I always use a Conspicuity visual-impact vest (they make a quality zip-front deluxe model that lasts for decades for about $60). I believe in very little in this world, but one thing in which I do believe, based on experience, is that if motorists SEE you, they will do all in their power to avoid a collision. It's not that they care about killing you personally, or wrecking your equipment, it's just that it creates too much paperwork, and makes them late for their appointments.

Seriously, the value of visual impact safety vests was brought out by the landmark 1979 Hurt Report(the only serious scientific study of motorcycle accidents ever done). Hurt found in studying 900 mc accidents in Southern California that about half of them occur when a motorist turns left into a motorcyclist at an intersection.

End of Part Four