he ‘07 Harleys are here and the good news isn’t limited to just a little more displacement. That 4 3/8-in. stroke 96-incher is now matched with EFI across the board, 6-speed transmissions and inside there are self-adjusting primary chain adjusters, hydraulic cam-chain adjusters, larger and more reliable plain-style cam bearings, a higher output oil pump, lighter connecting rods, lighter pistons, revamped cam timing, more compression and free-flow mufflers. The new bikes show real performance potential.
     So what’s involved when it comes to hopping up one of these things? No Harley stays stock for long and in the search for performance, whether it’s for off-road use or out-and-out racing, OE hardware always gives way to the aftermarket. 2007 is no different. So what about swapping those standard pipes and slip-ons for something from the Fatbook? A better-sounding, better-looking performance exhaust is the perennial Number One on most riders’ list. Same with the intake. Are changes possible here? Do high-flow filters and airboxes work on the ‘07s, and what about swapping that factory throttle body for something a little bigger? Can these time-honored Harley-Davidson modifications safely be performed on the ‘07s, and are the results worth it? The short answer is a resounding yes, in both cases. It all works, and it’s easily done. Of course, in today’s tightly monitored EPA environment all modifications might not be legal in all 50 states so it’s always advisable to check state and federal laws as to street worthiness before diving in with the wrenches.
     Now, here’s what’s happening. Dynojet Research, for starters, has already come up with a few specialized tuning maps for Power Commanders fit to the new Harleys. There are a couple maps out for the touring models and a couple more for the Softails. And Speed’s Performance Plus, that Drag Specialties vendor/dealer that takes the store and shop on the road all year long has already tested and tuned a number of the ‘07s, setting them up in their normal Speed’s Performance Plus “Stage I” configuration. They’ve tried different brands of free-flow slip-ons and full exhaust systems, they’ve installed different air filters including their own Speedy Flow Air Cleaner Assembly that retains the OE cover and the new SPP 90-degree Forward Mount Filter - both now in the Fatbook, incidentally - and of course they’ve included a Dynojet Power Commander III USB in the tune. The results: The modified ‘07s start easily, idle smoothly and run like gangbusters with a 15-percent boost in horsepower and torque.
     Wayne Hanson and the tuning crew at SPP began by putting a full selection of OE 2007 bikes through their paces, testing both on the dynamometer and at the pair of R&D centers they contract with in Mississippi and New Hampshire. They charted the factory fuel delivery and ignition curves and took note of all sensor readings during those tests. All those print-outs, coupled with plenty of closed-course testing, gave the techs at Speed’s a solid baseline to work from and a starting point to refer back to during performance tuning and hardware upgrades. OE performance documented, the changes began.
     The power-tuning sessions kicked off with the installation of Dynojet’s Power Commander III and the O2 sensor eliminators. The eliminators hold the sensor signal to the ECM, the bike’s computerized brain, at a steady 3 millivolts splitting the difference between the high and low range of the factory pre-sets. By taking that middle road they let the engine run right in the meat of the OE range. Dynojet’s pre-written maps for the ‘07s also use those O2 sensor eliminators; without them the factory sensors would override any changes made. With the sensor eliminators installed, however, power tuning the new 2007 bikes, Speed’s has found, is no different than a performance mapping session on any other fuel-injected Harley of recent manufacture.
     Plugging in a generic fuel-curve map - a good starting point to get a modified bike running correctly - is just that, a starting point. For optimum performance and efficiency it’s always preferable to custom tune that bike to the specific equipment installed, and with engine management tools like the Power Commanders that SPP uses and those sensor eliminators in the mix it’s all ‘07 do-able. And percentage wise the results for a custom “Stage I” tune on a new Harley are pretty much what you’d expect from an ‘06. While the long stroke/bigger displacement 2007 bikes start with slightly higher horsepower and torque readings, after a performance tune those numbers go up by approximately 15-percent. Speed’s also found that the ‘07 Harleys aren’t limited to just a few performance choices when it comes to pipes and filters, either. Everything available in the FatBook can be custom-tuned to the bike, as always.
     Bottom line: A successful “Stage I” package for the ‘07 Harleys encompasses everything we’re already used to, and that includes any exhaust and intake system a customer might want. With sensor eliminators and the PC III USB it can all be tuned into the 2007 equation. On the exhaust side there’s Hooker, Vance & Hines, Cobra, Samson, Bub, Rinehart, SuperTrapp - you name it, the list goes on filling pages of the FatBook. Speed’s personal Street Glide runs a 2-into-1 Rinehart, 2-into-1 systems generally the performance-tuner’s choice. But slip-ons, they’ve found, work well, too. And of course Speed’s used its own Speedy Flow Air Filter Kit with its high-temperature Viton O-rings to eliminate oil leaks and locking tabs to keep the bolts from working loose. The new Speedy Flow has a larger, deeper filter element, too, nicely sized to the TC96. For good measure Wayne always includes his One-Way Crank Vents to relieve crankcase pressure without allowing air to be pulled in on the up-stroke and clips on a set of his high-temperature/low-resistance plug wires. It’s also in the FatBook, and it’s not uncommon to pick up 3 to 5 MPG right there along with a bit more horsepower.
     A final touch for a total power-tune on an ‘07 Harley would be a new, larger throttle body and there are plenty available. SPP, for one, has a full range going all the way from 48mm to 62mm. There’s a 48-, a 51-, a 53-, a 56-, a 58-, a 60-, and a 62 mm size. That’s a lot of sizes, but they’re offered for a reason. That 56-millimeter unit, for example, works well on a 103-inch engine and it’s still pretty good on a 117 or a 124. For a 95-inch motor or a stock displacement TC88 it’s much too big. In those applications throttle response would be better with a 48- or a 51mm selection and for that new 2007 TC96 a 51mm throttle body, Speed’s says, would be a great choice. They’re in the FatBook, too.
The 2007 Harley-Davidsons are here, and they’re completely tunable. And as impressive as the gains are on these new, long-stroke 96-inch engines they’re even more eye-popping on the optional 110-inch engines. SPP’s power tuned a few of them, too. From a first-pull of 79 horsepower and 95 lbs./ft. of torque the after-tune numbers jumped to 94 and 113. Now that’s a nice package. We’re all just getting started here with the new Harleys and this year The Motor Company gave us a great bike to build on. The TC96 looks to be a heck of an engine and the FatBook is filling up fast with hardware to make it even better. Check with your rep today.

Installation of the Speedy Flow Air Cleaner.

The new SPP 90-degree Forward Mount Air Cleaner kit from Speeds Performance includes the “2-Step” air horn, a K&N filter element, mounting hardware and breather adapters.

Speeds Performance offers throttle bodies in many different sizes.

The Speedy Flow Air Cleaner kit from Speeds Performance.

The Dynojet Power Commander, probably the best-known Fl management system on the market, is perfectly capable of properly and accurately setting the air/fuel levels in these big-inch motors.