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2002 Sportster
NRHS Stage 2 Thunderstorm heads
NRHS/Axtell 1250 kit
NRHS HurricaneFlow Air Cleaner
SE .536 cams
Samson Caliber exhaust
Mikuni HSR42
Screaming Eagle nose cone ignition module (non-adjustable)
(tuned today)

Nice................

Nice two-peak torque curve. What did you think of that exhaust Aaron? Looks like it doesn't suck completely. Saw Danny Boy qualified third in Hot Street as did Friberg in Super Eliminator. Team NRHS keeps rolling on! :clap

Later,
Justin

It was an interesting exhaust for sure. the a/f plot almost mirrored the torque curve, which means where it wasn't pulling, it was pushing. That kind of annoyed me, I like flat a/f curves. The reversion wasn't terrible between the two torque peaks, but it was awful below 2500. Overall, I've seen worse, it wasn't a bad pipe.

Yeah, I thought Dan was in trouble until the last round, I was wondering what the hell was up. Haven't reached him, don't know if it was a tuning thing or a riding thing. But looks like he got his arms around it and is in the hunt. He certainly has the bike to get it done. The top 3 are within .08 of each other, so he has a chance. Didn't notice Mike, very cool.

Samson Caliber.... those real loooooong pipes?

BTW ... that's Rob Noble's bike above. He was there watching me do the whole thing and saw first hand how his SE air cleaner was costing him more than 3hp. The HurricaneFlow sells itself when you can show someone first hand what it does for his bike ;). He tried on both the centered and the offset and went with the offset, had better knee clearance for his forward controls setup than the SE unit.

Samson Caliber.... those real loooooong pipes?

Yeah, it was a 2 into 1 that came out way in the back.

Aaron, are those .536s really that good of a cam. I am looking for a little more cam but the duration makes me think it wouldn't be the best for just all round riding?

Am i wrong on this?

I know I have the JET heads but Bob isn't a big fan of big/long duration cams.

Bazza...

One of the problems with engine design is getting everything to work together well....

I've noticed differences between Aarons stuff and HQ or Jets stuff....

Aaron seems to get very good figures with larger cams, without losin as much at the bottom as one would expect....

To mix 2 different builders combinations together is not a recipe for success but rather dissapointment....

With the JET/stock heads I would stick with smaller cams......if you are getting the heads done at Aarons then I'd go with his recomendation which is normally for bigger cams than most of the other set up seem to able to handle well...

One of the biggest problems I see on street bikes (and this goes for street cars too) is most are over cammed and over carbed for where they are being used

That's what I mean. The heads are ported, 1.715I and 1.480E, 54cc chambers, 10 to 1 and some nice port work. I'm not sure about the 551s as they were designed for the 1200 chamber, valve to valve clearance, but the 536s are a nice spot between N4s lift and 551s lift. I like the mid range power but I also like to spin it up now and again and realy want the best of both worlds :D . I just don't want to lose the 82ftlbs I have now. But I would really like to get close to 90Hp on top.

The dyno above shows 82ft lbs. I basically am there now with 81.


I'm in a pickle, I know.....

536's are more a top end cam then the 551.....


Duration and intake closer ....longer and later = top end

More lift and an early close and more bottom end

I'm a big fan of the .536's, but I gotta go with Stevo, match the heads and the cams. I wouldn't go slapping them in with a set of heads that were ported around some other plan.

You gotta remember, too, that torque by itself says nothing about performance unless you also consider the rpm it's made at, and when you do that, it's called "horsepower". By itself, torque is not a performance metric, if it was, we'd all gear our bikes into the basement and leave'em in first gear all the time, because the deeper you're geared, the more torque you're putting to the back tire. We don't do that because speed DOES matter, and when you combine torque with speed and consider how much of both you can make at the same time, the term for that is horsepower. The motor making the most horsepower always puts the most torque to the rear wheel at any given rear wheel speed, it's a fact.

The .536's are actually very gentle on the valvetrain and don't need a lot of spring pressure at all. They run reasonably quiet and properly done, the valvetrain has great longevity. The only real issue with them is the late exhaust close point, this can cause a valve to valve clearance issue especially when used with larger valves. Also it causes a valve to piston clearance issue with a lot of the pistons on the market.

The 50 degree intake close event is a good place to be with 10.5:1 to 11:1 compression, and they have enough overlap to get good exhaust augmentation of the intake flow. Making a wide powerband with them is a function of properly sized ports and a well matched exhaust system. Exhaust systems just have a profound effect on powerbands, particularly with some overlap in the cams.

I ain't gonna knock Bob or Doug, we all have our understandings and experiences and those guys are successful with their approaches, so "more power" to'em. I do approach it differently, though, in particular I'm a big believer in CNC. I've seen what it can do for quality and consistency and our CNC-Flex process overcomes it's main limitation and gives us the ability to do custom work with it.

Arron - On the cam topic, if you were doing my stage 2 or 3 heads ('04 heads on my '00 motor) and I wanted to keep my V&H Straight Shots, what cam would you choose for street (under 6500 rpm) use?

Have you got a dyno sheet from that pipe? I don't know much about it.

Just on that note..

I've been runnin 0.536's in my sporty at up to 11.25:1 since early '99...;) FULLY streetable as daily transport....

I like 'em BUT I can feel what the motor is doin and I'm not afraid to rev it if I need to, even tho it rarely goes over 3500 on the street...I tend to stir the box and keep it between 2250 and 3500....it doesn't like bein under 2250 and it will "cam" below that rev.

I find that they don't suit a lot of riders, 'specially the ones that don't change down when they're overtakin...and my girlfriends sporty is quicker on top gear roll ons up to 130kph...then mine catches and just keeps goin to 7000+ in top..

Aarons repeatability with headwork means he can reclaim some of the bottom end that some other builders lose.....but at the end of the day ..

IT is the WHOLE package...NOT just a cam that makes the power.....the parts MUST BE MATCHED

Hey guys,Im a novice rider with a 1999 1200C with 10,000 miles on it---Im looking for the best set up,thats dependable,,looking to get like 80hp---Can I do this without heads or headwork??? Cams,pistons ,CV carb-worked,airclaner,Etc. Does any of that ignition stuff,like performace coils or ign. modules give HP??? 80HP has gotta be better than the ,what is mine stock,56 HP??? :tour Thanks

ASW---I like your stuff,but moneys a factor--also---these mods I wanna do---can I work the heads later down the road to work with these mods now???