From: utzoo!decvax!harpo!ihnp4!ih1ap!lrd Newsgroups: net.misc,net.auto,net.cycle Title: Who Uses Regular Gas? Article-I.D.: ih1ap.122 Posted: Tue Feb 8 14:51:30 1983 Received: Fri Feb 11 05:15:47 1983 Reply-To: lrd@ih1ap.UUCP (L. R. DuBroff) Larry West, UCSD, said, in reference to this topic: "Yes, but almost any motorcycle CAN use unleaded gas, if the rider chooses to pollute a little bit less." True, BUT -- 1. The contribution to atmospheric pollution, by all motorcycles, is less than 1%. Polluting a little less will be an improvement of far less than 1%. 2. Regular is less expensive than no-lead; using unleaded gas, at a higher cost, will increase your engine's tendency to detonate (pre-ignition, or knock). This is particularly noticeable on warmer days (when most motorcycles are used) with air-cooled engines (most motorcycles are NOT liquid cooled). Typical octane (anti-knock rating) for regular is 89, for unleaded, 87. Of course, if you don't like the engine knocking due to your use of the more expensive nolead, you can always pay even more for premium unleaded! 3. Unleaded gas causes MUCH faster wear on valves, valve guides, and valve seats than regular, both in cars and motorcycles. The combustion after-products of tetraethyl lead act as lubricants under the extreme high pressure and high temperature conditions that are encountered by valves (particularly exhaust valves). The use of regular gas will extend valve life by several hundred percent. Regular does have one minor drawback -- spark plugs last longer when unleaded is used, but I can change spark plugs in 10 minutes, at the cost of a few dollars; the cost of replacing valve components is in the hundreds of dollars! If your engine (car or motorcycle) runs properly on regular, you are wasting money and accomplishing very little by using nolead. L. R. DuBroff -- BTL, Naperville, Illinois