by Doug Loftgren
Whatever Happened to the Tune-up? The short answer is the concept of never having to do a tune-up has been sold to the public. It’s a marketing scheme. And it works. Look at the Ford commercials for the 100,000-mile tune-up interval. That sells cars. But bikes are not cars. Bikes are very high-performance engines (and always have been) and even though improved quality control has nearly eliminated the kinds of major failures that were quite commonplace with bikes prior to the ’80s, modern sport bikes do respond to the old fashioned tune-up.
When I worked in the engineering department of a major small engine manufacturer, the marketing department declared that they needed to increase the valve adjustment interval from 500 hours to 1000 hours. Did Engineering change any parts or materials? No, we just built a bunch of engines and ran them for 1000 hours without any valve adjustments. Oops! I take it back. They did change something, the printing in the owner’s manual. That is what has happened in the motorcycle industry, and for the same reasons. Don’t feel like you’re the only one for whom the cost of service is significant. When BMW had to offer a 3 year “all service” warranty to compete with Audi, they doubled their suggested oil change interval. When they had to pay, the cost became important. There are people in the BMW service business who think that this will eventually hurt BMWs reputation for reliability and quality.
Years ago, there were a few brand cultures that embraced a lack of service. Among that culture, it implied reliability. It’s been subtle, but this whole “no-tune-up” thing has crept throughout all of the motorcycle cultures. A real eye opener occurred several weeks ago while I was at a social event at a friend’s house. Of course, the place was filled with motorcycle people. A couple of the folks are Iron Butt competitors. I was shocked when one of them stated that he had 55,000 miles on his VFR and never had a tune-up! With all the planning, effort, and dedication behind such an event, I can’t understand how someone would enter a 9,000 mile event without having some idea that the engine is healthy.
Electronic ignitions have eliminated any need for periodic adjustment (although it is still listed among the things that are to be inspected with periodic maintenance.) So, that has changed since the “good-old-days”. Throttles still need to be synchronized. Good throttle response is elusive enough because of very lean light load emission requirements of current emission standards. Keeping all the throttles working together really improves response. Even though modern multi-throttle set-ups have a much better mechanism than the old multi-cable lash-ups, they still need to be synchronized after they’ve “seated in”. On the subject of synchronization, fuel injection systems are more sensitive to throttle synchronization than carbeurated systems. Why? When carbs are out of synchronization, each carb responds to the amount of air going through it, and delivers the appropriate amount of fuel. If the throttles of an injected system are out of synch, the ECU still dispenses the same amount of fuel to each cylinder with the mistaken assumption that they all pass the same amount of air. So, on top of the difference in air to each cylinder, (which represents a difference in power from each cylinder) there is a difference in fuel/air ratio. There are plenty of mechanical reasons that valve clearances should be adjusted, but the most compelling reason is more subjective. When your engine is spinning up to red-line, it’s nice to know the condition of your valve train. Small things like clutch adjustment, chain adjustment, and even lever adjustment, can improve shifting. All of these things work together to make a bike feel much better.
I can’t count the number of people I’ve encountered who think that the previous owner of their newly purchased pre-owned GSXR must have had a tune up. (Although the present owner declines to have it done, the previous owner must have been fast and loose with his $$$$!) Owners of new bikes are quick to say that they’re selling it next year anyway. What do they tell themselves when they’ve kept it for 3 years and it runs like crap? I’ve heard the lore that sportbikes always make the best power when they’re new. This is just garbage to confirm the fallacy that you can just buy it and never look at it again.
Why should you listen to me? Because I’ve been doing this for 34 years and hate doing tune-ups. And yet, I’ve learned that “the more you work on them the faster they get.”