ASW Racing, Sportster question

[Shooter1]

@aswracing,  you had posted the data below in response to a person considering a Sportster R in the 2005/2006 range. You had mentioned the '05 having a more robust cam tappet pin setup than the later model bikes. If you were going to build an R model that would put out say 90/95 HP and intended to put some miles on it, would you use an '05 model or use a newer '06 and up FI 1200R?
Thanks


2005 and 2006 XL1200C and 1200R motors use the same heads, the same cams, the same pistons, the same ignition and carb and air cleaner and exhaust. So they make the same power. However, they may dyno very differently based on the rear wheel. Spokes dyno the best, mags are in the middle, and the solid wheel (as found on many "C" models) dyno the worst. I'm talking about an inertia dyno here, which is the most common. On a brake dyno that does a steady state measurement, you won't see a difference based on wheel type.

The big difference in the motors between those two years is the tappet anti-rotation method. From 2000-2005 Sportsters used screw-in tappet pins. It's a solid, robust setup. In 2006 they went to a plastic anti-rotation device (cost reduction) that flexes with cams over about .600 lift. The 2005 setup is better.

Also there are differences in the transmissions between those two years. In 2006 the gear cut was changed to reduce noise and also the ratios got changed. I don't have all the details handy.

The stock cams are the "W" grind, which has very early intake valve close (IVC) timing at 25 degrees ABDC, which means it's a low rpm oriented design. In fact that's the earliest IVC of any Evolution Sportster cams available. So any cam swap you make will have a later IVC and thus a higher rpm range. Therefore if you do a cam swap without also swapping the ignition, you'll be missing out on much of the benefit of the new cams because your stock 6000rpm limiter won't let you get there.

For some dyno sheets showing what can be accomplished with good stage 1 pieces and bolt-in cams, go here: http://www.hammerperf.com/tthoppingup1200.shtml#camsalone . Those were taken on a 2007 which has an identical motor except it's EFI, and the EFI makes a bit more power. Derate those numbers 10% or so for a realistic expectation. Also, the EFI throttle body is bigger (45mm) as compared to the CV40 carb and it'll support more power. You'll find the CV40 starts choking the motor above 90hp. So above 90hp, you need to be thinking about a bigger carb. We like the Mik HSR series carbs.
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[aswracing]

EFI came out in 2007. 2005 and 2006 are both carb. So really, in comparing a 2005 to a 2006, you're looking at the tappet anti-rotation system and the transmission changes. Other than those two things, they're the same bike.

In 2007, of course, they all got the Delphi EFI system. It's an excellent EFI system if you want my opinion. There are some really nice tools available for it, too. It's been the focus of the aftermarket for a long time. Blows away what came before it, Magnetti Marrelli as found on later Evo Big Twins and early Twin Cams. Also blows away the Buell DDFI system. Both of those systems alienated a lot of HD guys away from EFI, including me. But the Delphi system won me over. This is all just my opinion of course, I'm sure you can find plenty of guys who disagree.

The EFI Sportsters make a bit more power, too, than an otherwise identical carb motor. Partly because the cylinders can be tuned individually. But the bigger 45mm throttle plate found in the EFI throttle body can also support more power than the CV40 carb. CV40's, in my experience, start really holding back a build at around 90-95hp. For the EFI, it's more like 105hp. And we've found that with some work, the factory throttle body and manifold can support builds up to almost 120hp.

We've found the same to be true of big twins, in fact we just had a customer with a 98ci Twin Cam send us a 120+hp sheet using a ported version of his factory throttle body & manifold (among many other mods).

So anyway, if you're asking which one I like more, a carb'ed rubber mount Sporty (2004-2006) or an EFI version (2007+), personally I'd choose the EFI. But that's just me. There are plenty of guys who would rather have a carb.

[PC_Hater]

I like EFI when everything is working properly, but I prefer a carb when things start going wrong!