OK, promised I was going to test these, did it today, here's the result:

http://www.nrhsperformance.com/images/575vs536.gif

This bike also has a 1250 kit, Stage 2 '04 heads, 6800rpm ignition module, Mikuni HSR42. Stock lifters, Hurricane fixed length (non-adjustable) pushrods, stock rockers (although rollers aren't a bad idea at this lift). CR is 10:1.

More power on top without losing anything down low, I always like that ;)

Don't read too much into that low rpm advantage, I'm rolling into the throttle at low rpm and it's not a real repeatable process. I probably gave it a little too much too soon on the red pull. The other pulls on that cam set didn't have that issue.

The 575's wanted one jet size fatter on the main, I went from a 165 to a 167.5. Timing was set for max power on both cam sets.

Both pulls were done on the same bike, same dyno, same day (less than 3 hours apart), same operator (me).

The valve springs in these heads are moderately light pressure, about 150lbs on the seat after break-in, and are well broken-in. By comparison, a stock spring settles down around 120 after break-in. Lots of bigger cams need 180 to 200 to control the valvetrain properly, or even more (I have a race motor with .785 lift cams that need 270 on the seat). So 150 is not a big number. Should have good life and not tear things up. Part of this experiment was to see how these cams would work at moderate pressure. No signs of seat bounce in that chart. The lobes don't look aggressive, either.

As far as valvetrain noise goes, so far I can't tell any difference between these and the 536's. I reserve the right to change my mind as I ride it more, I've only done dyno time and about a 20 mile ride home from the shop. They certainly don't sound anything like the 551's did.

I would expect these cams to show more advantage at Stage 3 on the heads, since much of the improvement on a Stage 3 head comes in at higher lift.

So all in all, these new cams sure seem like a winner to me.

ard to believe a properly tuned stage 2 bike makes over 100 h.p. wish I was there for you to tweek mine a bit. Thats simply superb. Maybe I need to ditch my n8's for a set of these. Do you have to cut pockets into the pistons for these cams?

I was actually kind of annoyed by that 101hp number. This is the same bike that was making 103.5 easily last June.

I rolled it on the dyno today, figuring I better re-test before I swap cams. It was only pulling 95hp and showing real lean. I checked it over for intake leaks, nada. Ran compression and leak-down tests and everything was fine. No oil usage or anything like that. So I was stumped and finally just changed the main jet. Fattened it up and it came up to 101hp as shown. Fiddled with the timing but it was already dead nuts perfect.

Here in Colorado our gas gets oxygenated in the winter, I think this was gasahol. I'm thinking that's what made it go lean and probably also accounts for the 2hp loss since June.

TDC lifts on these 575's are .228 intake and .221 exhaust. So they're not terrible hard to install like a lot of racing cams are. Hurricane pistons have enough room unless someone gets real crazy with the head milling or doesn't set up the stem protrusion correctly. Stock pistons, probably not. At 1.850 intake/1.615 exhaust valve sizes, valve to valve is OK with these cams with stock stem protrusions. With a 1.900 intake valve (ala Stage 3), we'd likely need to do a little valve sinking to make it fit.

I didn't have to do any cam box clearancing, although it was close in a couple spots. These are small base circle cams and that helps with the cam box issues a lot. Ditto anti-rotation pin clearance.

So in the grand scheme of things, this is not a difficult cam set to install, clearance wise. The main thing is you need the heads set up with longer travel springs, slightly higher pressure springs, and shorter guides (for retainer to guide clearance), but that's all standard at Stage 2.

OK, now for the $400 question. I see you ran the .575s with stock rockers even though you recommend using roller rockers for lifts over .500. Is this safe on a stage 2 street motor. I kinda would like to spend the $400 on something else if I can. Also, why not use stock pushrods?

Man, you guys ask good questions. I normally reccommend roller rockers if you're going above .550 lift, and they start becoming mandatory at .600. But spring pressure plays a role in that. At lower pressures there's less friction at the rocker tip to valve interface and side loading won't be as bad. I'm not overly concerned about this lift and pressure with stock rockers. But I'll keep my eye on the valve tip and guide wear and reserve the right to change my mind.

Stock pushrods are very flexible, even with stock spring pressures, so a heavy duty set is always a good thing IMO. In this particular case, there was another reason as well. These heads come out of the box .020 shorter than a stock 91-03 head. After a little milling to get things perfectly flat and careful selection of gasket thicknesses to get proper squish clearance (this motor has no base gaskets for example, because that's what it took to get the squish right), we end up dropping the height of the top end quite a bit, enough that pushrod length becomes a concern. The small base circle on the cams helps offset some of this but not all of it. Anyway, the Hurricane pushrods I have in this motor are .040 shorter than stock for exactly this situation. It's a piece we keep in stock just because we see this situation so often. They're also .065 wall heat treated chrome moly with Mae West ends. So it's a nice, stiff pushrod.

I really prefer to be able to use stock lifters and pushrod covers (i.e. non-adjustable pushrods) when possible. Holds costs down and doesn't need periodic adjustments and reduces the number of seals and potential for leaks. A non-adjustable pushrod is inherently lighter and stronger than an adjustable as well. With more aggressive cam grinds though, the spring pressures and rpm's are such that a travel limited lifter becomes essential (solid or hydrosolid), and that means an adjustable setup, as well as roller rockers. Sure drives up the costs, though.

How do you measure the required length of a pushrod?

What sealant do you use on the base for a gasket and how long does it last?

Is the proper squish measured in compression ratio or is there some other measurement tool?

Are you using metal head gaskets? Like cometec.

Wow, more great questions.

"How do you measure the required length of a pushrod?"

One way is to put it together and discover you've got low or no compression and major leakdown. Not that I've ever done it that way ;)

The better way is to put the rocker box in place with the 4 large bolts started and the rockers resting on the pushrods and valve tips (motor positioned such that both lobes are on the base circles). Finger tighten the spark plug side bolts and measure the gap between the top of the head and the bottom of the rocker box on the pushrod side. You'd like this dimension to be about .100, because the tappet plunger has .200 of travel, so .100 of preload would center it. If the dimension is up in the .200 range there's a good possibility you'll hold the valves open after tightening down the rocerk box.


"What sealant do you use on the base for a gasket and how long does it last?"

3-bond 1104 and indefinitely.

"Is the proper squish measured in compression ratio or is there some other measurement tool?"

An easy, effective, and fairly accurrate way to do it is with strips of .065 solder strategically placed on the squish band (I usually hold them in place with a dab of grease). Torque the head on, roll it through TDC once, pull it off again, and measure the thickness of the solder strips with a caliper. .030 to .035 is a good range.

"Are you using metal head gaskets? Like cometec."

Yes, we've had tremendous success with the Cometic MLS gaskets and that's all we sell. It's the only gasket I've found that will hold on my nitrous race bike, making over 200hp on the juice. I've blown out every other gasket made I think, but never blown a Cometic except once when a head bolt broke.

So heres the bottom line question. I'm getting 2004 barrels and heads for my 2000. Will have you do stage 2 head work, bore and hone. Will be using hurricane 10.5 pistons, Hurricane flow 2" AC, TC88 ignition, and V&H Straight Shots. I like to rev the bike, and have changed to a 65 tooth rear pulley. Which cams for me, .536 or .575?

Okay...here is a great question for you...although not as inteligent, it still represents an inquiring minds thirst for knowledge.
WHAT THE HELL ARE MAE WEST ENDS ON THE PUSHRODS?

I believe it refers to the hourglass shape at the rocker arm end of the pushrod. It helps keep the pushrod from hitting the edge of the pocket on the rocker arm.

Sham, the 575's are working pretty well, and I haven't seen anything to suggest to me that they're hard on the valvetrain, which was my biggest fear. There are some grinds out there, in this size range, that are just brutal on the valvetrain, stuff I'd never put into a street motor myself (although I know people who do). All indications and measurements are telling me these are mild and unless and until I see something that tells me otherwise, I would expect them to have good longevity. Clearly they're capable of performing a little better than the 536's.

Kerry, cjburr is right, although it has more to do with the shape of Mae West's most famous anatomical feature. The rounded, bulging tip of the pushrod allows it to go to a more extreme angle in the rocker arm pocket, which keeps it from wedging out at high lifts.

Glad you explained the mae west thing, all I could think of is her cleavage and that is where my imagination stopped.

No worries ...

and before someone asks, here's the torque:

http://www.nrhsperformance.com/pictures/575vs536torque.gif

They look like a decent grind......may have to look into a set as appear as tho they'll be a LOT easier on the train than the N9's I've got here...which I'll use in at least one setup as I have a few sets



:)

It's always pleasant to see others do things the way ya do yaself...

I use solder for quench/squish and hold it in place with platicene or modeling clay....as I use that for the valve pockets as it allows me to how muc I have around the periphery of the valve in the pocket...


and I use mostly 3 bond or yammabond on metal to metal surfaces



Although I tend to use solid copper head gaskets as I've been using them for years and I either make them myself or get them made for me.....

Have not had any problems with Cometics tho and use them on cutomers bikes regularly and I use cometic or James metal rocker gaskets

Yep yep yep.

The N9 is a pretty similar grind actually. Very similar timing, a little less lift, and a more aggressive lobe. Besides the lobe profile, the other big reason I haven't put many people in them though is the overlap & resultant tdc lifts, you gotta look at things pretty closely when you install them. I don't mind if I have the motor here but we send out a lot of kits and most people don't want to mess with claying the motor.

You bring up another good point on valve to piston clearance. More times than not, with a big valve, the clearance problem isn't the depth, it's the perimeter, what we call "eyebrow" clearance. And it's all too easy to weaken the piston if you over-clearance it, because it's so thin between the pocket and the top ring groove. So you have to do it very carefully, and radius that bottom corner of the pocket. On race motors I don't mind seeing the valve do the last little bit of clearancing for me, so long as it doesn't bend it. It's actually a good way to get it just perfect without weakening the pocket any more than necessary.

The only problem I have with the Cometics is that sometimes customers put o-rings on the dowel pins. Leaks every time if you do that ;) Oh, also, they have to know to watch for the rivets getting sandwiched, and they've gotta know the torque procedure is different. But if they read the instructions, they're fine, and the gaskets work great.

Yeah I run a different torque setting for my solid copper ones too.....

and I tend to run a lot tighter clearances on motors I put together myself than parts that are going to customers.....

Not that it's really one rule for me and one for them .... but I prefer to leave larger margins when I don't have the final control

I also have a set of posts as a dummy cylinder so I can do an assemble and check valve to valves as it's not always at TDC that they get close...usually just lok in thru the plug hole or use wire but with a new cam I prefer to take a bit more time and watch it the whole way..... I'll be usin that for the N9's as it would appear that's going to be a concern

most copper head gaskets I don't use O-Rings on (unless it's watercooled)... but I've got one customer that sat at over 100mph for hours on end across the Nulabour on his softail and it's warped the top of the barrell slightly near the exhaust and I had to ream the gasket and fit and O-Ring as it was seeping oil out......still had integrity on the other side tho....
I'll fix it properly later as he wants more power :D so I gotta go in a get some more ponies out of it ..... but sometimes ya gotta do running fixes..

Ok, don't know if these are good questions, but here it goes anyways...

You say that the valve to piston clearance may be an issue on stock pistons - does this matter for the year? I was under the impression that 2004+ 1200 pistons were dished from the factory, so would this still be an issue on an 04+ machine?

Also, how much difference does 50cc more and .3 higher compression ratio affect the numbers? And how big of an improvement (lower, mid and upper rev ranges) will a stage 3 head job do? Your best guesses will be fine.

BTW - Is squish the same as quench???

So are the .575 as noisy as the .551 cams ?

The 575s are nowhere near as noisy as the 551s. Our stage 3 headwork combined with 575 cams can net you upwards of 110 rear wheel hp as long as the rest of the components are of equal quality to match.

Man, you guys ask good questions. I normally reccommend roller rockers if you're going above .550 lift, and they start becoming mandatory at .600. But spring pressure plays a role in that. At lower pressures there's less friction at the rocker tip to valve interface and side loading won't be as bad. I'm not overly concerned about this lift and pressure with stock rockers. But I'll keep my eye on the valve tip and guide wear and reserve the right to change my mind.

After reading this thread I was wondering if you had put some more miles on the 575 equipped bike. Has the valve train shown any excess wear? Sorry if this has been addressed elswhere.

Part of the reason I ask is that I have a set of 575s. Got a very good deal on them. Of course, if it needs roller rockers, it's not such a good deal anymore.:( In that case I'd probably just go with 536s. The more stock valve train stuff I can use the better $$.:)

Thanks in advance.

We have put enough miles on the 575s to know that they are very good cams and they have been 100% reliable. No they have not caused any excess valve train wear. You do not need roller rockers to use 575s but you do need at least stage 2 headwork. They will not work with stock heads.

We have put enough miles on the 575s to know that they are very good cams and they have been 100% reliable. No they have not caused any excess valve train wear. You do not need roller rockers to use 575s but you do need at least stage 2 headwork. They will not work with stock heads.

I have SE 575 cams with NRHS stage II head work along with Hurricane 1212 pistons on a 2004 Roadster and the bike is surprisingly civil, idles as smooth as stock. I highly recommend this set-up for a very street able bike.

My 2¢ ¿Where's the cent key?
JB

I have SE 575 cams with NRHS stage II head work along with Hurricane 1212 pistons on a 2004 Roadster and the bike is surprisingly civil, idles as smooth as stock. I highly recommend this set-up for a very street able bike.

My 2¢ ¿Where's the cent key?
JB

What kind of HP are you putting out and what AC and exhaust are you using? I ask because I will be starting the 1212 w/the Stage 2 883 heads real soon.

What kind of HP are you putting out and what AC and exhaust are you using? I ask because I will be starting the 1212 w/the Stage 2 883 heads real soon.

Forcewinder, only for legroom, and Cycle Shacks slash cuts. Also a Twin Tec TC88 ignition module and a Mikuni HSR-42 carburetor. My bike was dynoed with a failing crank position sensor, not the most optimum conditions, and the HP was in the 89 to 92 range. I believe another dyno test will yield a few more HP. I could be wrong but I don't think my set-up will make 100 HP. I didn't build my bike to be a dyno record breaker and specifically requested NRHS, whom advised me, for the bike to be civil.

JB

Can you run the big bore SE CV carb in this kind of set up and still get good power? I am asking because of the obvious benefits of the CV carb.

Oh and another question. What kind of power number hp and tq could you expect from a 1250 kit with SE536s and the stage 2 or 3 headwork?

The 44 cv has some bowl vent issues according to some sources... and may not be as good a choice as one would think...

Have had no issues on the few I've played with .... but I havn't pushed as hard as some... and it may only be with certain set ups..

Aaron can probably answer more because I think he's come accross a few hiccups with 'em

Yeah, I'm not a huge fan of that carburetor, and personally I think the supposed advantages of the CV design are highly debatable. I've spent a lot of dyno time trying to get them right on occassion, they're incredibly sensitive to that bowl vent as Stevo mentions, and it's difficult to get a nice flat a/f curve. We'll sell'em to people if they insist, but I warn them right up front, if it fights me on the dyno I'm gonna charge extra for it, I can't afford to eat that.

Once a person uses a Mikuni and sees how sweet the motor runs and how easy it is to tune, they generally lose their desire to get a CV44.

We've had lots of customers do Stage 2/3 with .536's, it's a very popular combination. Here are some examples:

http://www.nrhsperformance.com/images/drrobnoble.gif

http://www.nrhsperformance.com/images/drdandunn.gif

http://www.nrhsperformance.com/images/drartbartlett.gif

http://www.nrhsperformance.com/images/drbarneyhertzog.GIF

http://www.nrhsperformance.com/images/drrichmartinez.gif

http://www.nrhsperformance.com/images/drbobkasper.gif

http://www.nrhsperformance.com/images/drdannorlin.gif

http://www.nrhsperformance.com/images/drlarrygillam.gif

All of these are 536's and Stage 2 or 3 heads. That last one was done with a CV44, the others are all Mikunis, except the Buell X1 which is injected. More info on each of these setups in our dyno room: http://www.nrhsperformance.com/dynoroom.shtml

Thanks for the information. Some food for thought. I am currently taking Screaming Eagle 1 at MMI Orlando. SO a lot of this is now making sense to me lol.

I have a question about setting the squish. Say you're using Cometic head and base gaskets. After you torque the head down and turn the motor over, then you take it back apart to measure the solder, can you still use the same gaskets or would you need to use a new set?

Excellent question, and the answer is YES, you can re-use Cometics. They don't crush permanently like many gaskets constructions do.

We often re-use them even after running the motor, it's one of the reasons I like them so much on the race motors, which we're inside of a lot. I usually use them until the rubber coating starts looking shabby. But for a simple torque down & removal without running the motor at all, there's zero wear.

Excellent question, and the answer is YES, you can re-use Cometics.

Thank you very much for the reply. That's a question that's been bugging me for a while.

Dan, I got 200 miles on the motor today, she's doing good. I can' t wait until I can romp on her. Thanks again for all the help via e-mail.
Jes from Okinawa Japan

the issues you discussed with the 575's. How about the Redshift 567's? same topics with installation, roller rockers, pushrod lentgh, spring pressure and so on???

what components are needed (assuming good tuning) to get to 110hp on an 05 sporty?

I got the stage 3 with 1250 kit, 575's, 2" hurrincae intake, pushrods, SE 7k ign(going with a TC88) and an RB 2-1 pipe.

what else can i change/do to hit that mark?