Care for something a little different?

Care for something a little different?

Oxford (23 October 2013) - Harley-Davidson has been celebrating its 110th anniversary throughout 2013. Yes, that’s right, 110 years of Milwaukee Metal production. It’s also a fair bet that motorcycle media has been around just as long and that all of H-D’s models have been tested by the motorcycle press at some point, either on their own or in group comparison tests. There is also another form of machine test called ‘long-term testing’ whereby a journalist or magazine is given a bike for an agreed length of time – usually from April to the end of October and more commonly known as the riding season.
long-term tests

Long-term tests usually involve a new model and enable readers of bike press to read first account on what a new bike is like to live with. Long-term tests are viewed as research information by people who want to buy the same model new or, indeed, second-hand. But while it may look like a good marketing/advertising tool for manufacturers, long-term tests can in some cases also highlight problems.

Harley-Davidson UK has always assisted with requests for long-term tests. Obviously not every publication (motorcycle or lifestyle) gets a long-term test machine and more often than not, long-term test bikes go to media that best represents the brand and encompasses Harley-Davidson® owners and fans.

This year, Harley-Davidson loaned three motorcycle titles a bike each from its large range of machines. Ped Baker from MotorCycle News asked for a Dyna® Street Bob® 103 in Denim Black; Ride magazine’s Colin Overland took charge of a Street Glide® from the Touring range; and Julie Brown of MSL (Motorcycle Sport & Leisure) took a shine to the new 1200CA Custom Limited Sportster®.

Each of the bikes’ keepers, like any Harley® owner, would be free to personalise their chosen motorcycle from the vast array of genuine Harley-Davidson® accessories and, of course, have the usual benefits of 12-month membership to H.O.G.® UK. The bikes were also subject to the usual servicing requirements. However, this year Harley-Davidson UK & Ireland decided to try something new with the long-term machines…

Many non-Harley people believe that a Harley is there to be ridden and customised and nothing else, and also they are very basic when it comes to technical matters. In order to prove this is not the case, the three long-term test bikes were treated to a subtle engine upgrade package of Screamin’ Eagle® Performance camshafts and freer breathing air filter kit (one of many from the P&A catalogue).

The camshaft kit (two cams) fitted to the bikes provides great low-end torque along with good midrange and top end drive and is best described as a good “all-around” cam kit. Of course there are four additional cam kits available for greater performance from the OHV range of engines. The only give away to the casual observer of, say, the Street Glide’s performance upgrade is via the Screamin’ Eagle Chisel Extreme billet aluminium air filter assembly. Finished with durable black anodising, this air-filter assembly is engineered to flow high volumes of air and requires recalibration of the ECM (Engine Control Module) to match the fuel-injection to the greater air flow.

Maximising the air filter and camshaft modification is a Screamin’ Eagle Super Tuner that aids compatibility of increased inlet airflow with fuel requirements and additional performance accessories such as the camshaft kit. Essentially, the Super Tuner is an official Vehicle Communication Interface device that allows pre-programmed modifications to the ECM via a USB patch to a software enabled PC. This link also allows online updates from official sources. This system ensures tuning functions are combined into one easy application of only two clicks away from any tuning maps or recent calibrations developed by professional Screamin’ Eagle calibrators. Software for the installation is, of course, held by official Harley-Davidson® dealers.

Of course, like all ECM modification tools (Dynojet, Yoshbox etc) used for performance upgrades, the Screamin’ Eagle Super Tuner was originally devised for racing applications and is, therefore, one of the most up-to-date systems available. Not forgetting that unlike other ECM tuning systems, Super Tuner adds nothing to the bike because it is our own internal software and writes directly direct to the ECM. The interface unit (VCI) is only connected to the bike when new calibration data is being written directly to the ECM. Once the calibration is uploaded the interface unit is removed from the machine and so no onboard space is used and the bike’s clean lines are left intact.

Although the system of installing pre-determined tuning maps is easy, there is nothing like setting up your own bike on a dynamometer (dyno). With that in mind we took the three keepers of the long-term test bikes to Harley-Davidson’s European Technical Training School in Bromsgrove – a modern college-like facility where Harley-Davidson dealers across Europe send their Master Technicians for product training – to show how ‘technically up-to-date’ Harleys really are. Oh, and to show how effective the performance kit is on their bike. It’s a little known fact that Harley-Davidson is the only manufacture providing performance engine tuning training for its technicians!

First off the journalists were treated to a classroom lesson on the general effects of camshaft timing and compression ratios on engine performance before moving into the heady world of volumetric efficiency, wide-band Lambda sensors, the actions and combined action of the 13 sensors linked to the ECM and much, much more. Going by the wide-eyed silence and note scribbling, it was pretty obvious the three visitors were now seeing Harley-Davidson on a level footing with regards to modern engine management technology.

The next lesson involved the use of the dynamometer, which is essentially a rolling road that allows a technician, with the use of computer software, to measure a bike’s performance output of torque and power at the rear wheel. At the same time, with the aid of a Screamin’ Eagle Super Tuner, adjust their bike’s ECM to match the camshaft revision and air filter modification that had been carried out. Needless to say the three visitors were very impressed with the performance increases. Not just in outright, high rpm figures, but also in the way the midrange drivability had improved with additional torque and horsepower. Increases are typically 20-30% above standard but can vary from model to model.

So how do the bikes perform on the road now? The proof, as they say, is in the riding: “The more I ride the bike…’ says Ped Baker about his Street Bob 103, “...the more I appreciate just what a difference it's made. It's most noticeable when accelerating hard up a hill. Before, the motor ran out of power fairly early needing big handfuls of throttle to keep up the pace. Now just a whiff of extra throttle does the job, and the bike never feels breathless. There's also a much stronger connection between throttle and engine speed, the motor’s reaction to rider input is instant; before the connection felt wooly. This is a double edged sword though as it necessitates a much steadier hand riding through town or down a bumpy road.”

Julie Brown from MSL is equally happy with her revised Sportster 1200CA: “There’s definitely a new found ease of use – the flexibility from that extra midrange and an ability to just hang onto the revs a little longer in each gear making overtakes much more confident. My Sportster now has real stomp to it yet feels more relaxed at motorway cruising speeds too. Worth having done without a doubt.”

Talking about his Street Glide with a smile, Colin Overland of Ride magazine has this to say: “The standard Street Glide isn't in any way short of grunt. The engine upgrades to my bike have boosted power and torque across the rev range, but where it's most useful and most welcome is in the low and midrange. Coming out of roundabouts, or doing 50-80mph overtakes, you just flex your right wrist and you're gone. It feels freer revving too, although that may be down to now having nearly 5,000 miles on the clock, or perhaps it's an illusion caused by a tweak to the exhaust that's made it slightly louder at lower rpm, so you hear that characteristic Harley noise when you're accelerating, however effective your earplugs.”

All Harley-Davidson® motorcycles can be adjusted in many ways to suit many add-on parts. Looking at the three long-term test examples with their basic performance upgrades tells you what can be achieved very easily. Camshaft and air filter fitting time is approximately four-to-five dealer hours and perhaps an hour to an hour and a half dyno time – if you want a custom made ECM map. Cost of the performance upgrade kit as used on the three bikes varies according to model so check with your local dealer first.

What we can tell you is that it can work out a lot cheaper than the price of replacement performance exhaust before it is even calibrated to the bike’s ECM. Cheap performance from genuine parts is always a good and welcome thing. Be sure to tell your friends as well as your insurance company; like all bike modifications it needs to be reported.

For more info on H-D genuine motor parts and motor accessories visit your local dealer, or go to: