I remember back in the 80s, Alfa Romeo improved the 0-60mph time of their GTV6 with slightly taller gearing.
Shifting can waste time.

 

My friend had his 883 converted by an H-D/Buell dealer for about the same cost as the normal conversion,
but they used cams & heads from 103hp Buell.
His '06 isn't EFI, so they put a larger carb on it.
I've ridden it, it's really fast.
We both changed to taller primary gearing.
I don't think a Buell case attaches to the frame like '04-'13 Sportsters.

 

O.p. you have a ton of different options you can do, read up on hammers website. You can go from mild to wild. I'm a firm believer in there services and parts, I've had two different awesome performing engine packages from them. Very street friendly and very powerful.

I was always told there is about a 16% difference from crank to rear wheel hp....crank being higher....not sure if that is true. The 98-02 buell with thunderstorm heads made 103 at the crank and around 85ish to the tire , give or take

 

I saw this on the XL forum and I think it says it all:



The Hammer guys were the brains and know-how for nrhs but now they stopped helping nrhs and there just killing them there so far ahead.

 

Why was Doug Grover's 1250 so slow?

 

Actually thats a pretty awsome post with the mapping of everyone's quarter times! I love my bike don't get me wrong, I certainly wouldn't want to trade it but I would like to be able to push past 120 IF I wanted to and be able to some extra pull and power around town and especially the highway. 80 isn't terribly difficult at all but 80-90+ is a much slower climb then say 40-60. End game I would like to have a a cafe'd sportster with some lungs on it, I ride with a Buell and 2 R6's fairly frequently so I am the slow fat kid out of the group but I don't mind and they aren't jerks about it at all. But I would like to be able to stay relatively in the same speed range IF possible while still being reliable and all that good stuff.

The question on the Buell conversion was because I had been looking for info on the 1250 conversions and I had read this mentioned more than a couple times. Some people were saying it was a direct bolt on but it does seem to be an incredibly rare conversion. Thanks for the info guys, pretty sure I'm leaning towards Hammer. I'd ideally like to do some performance mods and stay in the 1k range for now and slowly add on more as more funds become available. I appreciate everyone input, thanks again!

Also I forgot to mention that I am currently still under warranty. What would you guys do in this situation? Upgrade through the dealership to 1200 and get some better heads and cams or possibly void my warranty with the Hammer 1250? I need to double check the warranty info as to what will void it but I'm pretty sure this likely would.

 

Zane, here's the deal ... through the 2002 model year, Buells and XL's shared the same motor platform. The Buells had better heads and bigger cams and lighter flywheels, and made more power, but it was the same platform, and moving a Buell engine into a Sportster was not a big deal.

Starting with the '03 model year though, Buell went to the "XB" series, which is a whole different bike. The cases changed radically and they would no longer bolt into a Sportster. Some parts could still interchange, but not many. Mainly the top end stuff. XB heads could still be fitted to Sportsters.

Then in '04 a radical change happened to the Sportsters in the form of a rubber mounted motor. The cases changed quite a bit. This basic arrangement survives to the present bike. But it's not the same as the Buell XB setup at all. There's no interchangeability with the motors.

So basically, in 2002 the two motors diverged, and they're not the same anymore.

Now, in terms of grafting Buell parts onto Sportsters, well, the cylinders & pistons will move over. The heads will move over up through the 2006 Sportster model year, as in 2007 XL's went to EFI and the heads changed somewhat. The heads need to have their breather holes milled and drilled and tapped, so they're not a straight bolt-on, but using XB heads on Sportsters is a fairly common thing. Madnss has XB heads on his Sportster for example. Silver XB heads in particular are popular when doing a conversion on a silver motored 883.

But in terms of your bike, being a new one, there ain't much from a Buell that will move over, and the pieces that will move over offer no real advantage. The Buell pistons are nothing special and won't work with your heads anyway.

That's just about the extent of it. XB cams will not go into a Sportster without a lot of trouble, but HD offers the XB cams configured for the Sportster motor in the form of the SE .551 lift grind. Not a very good grind anyway if you ask me.

At one time, moving Buell engines or parts from Buell engines to XL's made a lot of sense, but those days are long gone.

 

There you go, can't get any simpler than that!! :P