Coming from a carburetor as well as a pair of injector, a well calibrated gas mix won’t deliver the performance it can give if it isn’t lit off at the right time together with a strong ignition. That special fuel demands an equally improved ignition system and professional bike techs understand how this works. At a pro tuner's shop, an ignition upgrade is always important in this project plan. Maybe some hot new coils, definitely an adjustable control module, top-notch plug wiring, and performance quality plugs to match, that makes up the components checklist. But first come the basics, the almost regular ignition issues that occur at times.
When a bike comes in spitting and coughing with an ignition problem, a coil might be shot, a plug fouled, or, and this happens a lot, the guy might have gotten a little too fancy trying to hide new plug wires but actually caused his problem by letting those wires rub up against something or get pinched and broken. This is not a long repair by a mechanic, but it’s a shame to only hang on a minute.

Just a few upgrade parts and a “dyno tune” from the ignition pays off much, and the more modified the engine the more essential that ignition upgrade becomes. Forgetting the ignition, particularly the advance curve, and you will be leaving much of the gains from any performance pipes, pistons, cams, and heads that you could already have directly on the table.

Using a fuel-injected bike that customized ignition tuning, setting the timing can be performed using the same Power Commander that the fuel distribution. Also, too, putting advance where it is necessary or taking some away 1 degree at a time at 250 rpm sets from idle to red line. With a carburetted motorcycle it’s just about the same story, differing simply in the way you arrive there. Speed’s uses the plug-in Daytona Twin Tee modules on those motorbikes and with the Twin Tee software, calibrates the ignition just like it'll be carried out with a Power Commander, straight down to the option of multi-spark settings and single-or dual-fire.

About thisslightly older Harley's, pre-Twin Cam, would fire both spark plugs simultaneously. There can be cons to that. Though one plug is lighting the charge within the cylinder ready for it, the other one is firing off in a cylinder that is not ready for its power stroke. If any extra air-filled fuel charge is left in that cylinder, which happens to be the situation, this will ignite as well. That can have an engine simply functioning against itself. Set up to single-fire a Harley is a much smoother-running motorcycle.

In addition to customized calibration, enhancements to the coils, spark plugs, and plug cabling make sense, too. High-output coils, providing as much as 45,000 volts, will clearly produce a smoother-running, easier-starting engine. Matching these hi-po coils using the finest set of low-resistance cables you can buy is another good move. True, due to the relatively brief lengths involved with bike applications the energy decrease in spark plug cables isn’t that great. But OE-style carbon-core suppression cables can, and do, degrade. Solid copper-core cables, however, aren’t often best with those adjustable ignition units.

An excellent replacement, savvy bike techs have found, is a spiral-core kind plug wire, easily available. Several spark plugs aren’t made the same, either. Iridium tipped plugs  are actually created specifically for the performance junkie. Yeah, they are a little more expensive, but apart from easily firing that mix, they already have excellent anti-fouling characteristics. They last. Selecting the best heat range for those plugs is essential, too.
Modified motors, specifically when the pressure have been bumped up, will normally demand a differ from the stock spark plug specifications. When the compression increases also goes the the heat, also, since spark plugs have to cut heat, a colder heat range plug might be required. Ignore the ignition step in a performance tune and you’re missing out on a lot. As soon as squeeze those harley hand grips to rev up and speak to any tuning pros, they will let you know.