More R&D from Frank

[OB_Brock Davidson]

Bob,
The main difference between the car and bike world is the efficiency of the stock
components. Especially the cylinder head.

The volumetric efficiency of a late model
sportbike is a thing of beauty! If you dramatically increase the lift/duration of on one of these machines.....you generally end up with a pooch.

The bikes are designed very well from
the factory, but they have to deal with emissions and a set rev range.

It seems to be a trend lately for the factories to install an extremely short duration exhaust cam in these bikes.

Web-Cam (909) 369-5144 has the stock cam specs, they regrind the stock cores for their cams.(general rule: American aftermarket.050.... Japan 1 mm)

Increasing lift/duration mildly will help the stock machine. More aggressive ramp profiles do help the performance, but lead to float/accelerated wear.

The real performance increases occur with a moderate cam increase in conjunction with
additional compression and the ability to rev higher without valve float. Even with a stock (or "cleaned up")cylinder casting. They are that good!

You have probably confused some
here with lobe separation angle. As you know, this is set by the manufacturer of the car camshaft. On bikes, we can adjust the intake and exhaust cams independently, producing our own lobe seperation.

Brock

 

[OB_Brock Davidson]

Frank,
My system uses a completely independent ignition system . Replacement coils, wires, trigger etc.

This system, in conjunction with a Schnitz Box controls: High limit, fully progamable ignition advance curve, shift kill time,nitrous retard,shift light, 2-step, autoshift etc.etc.

The stock ecm does not know it is no longer firing the coils, it only controls the efi.

Brock

 

[OB_ducmanic]

Thanks Brock, and Frank, and Bob for bringing some real useful information to org. This is what we need more of. My bikes still stock, but i love reading this stuff-
ducmanic

 

[OB_Johnnycheese]

Every word you said is the truth. I have set cams with " zero lash " and at spec. no differance just alot more time if under bucket. also moving the powerband is a very valid point. I always get one or two customers tell me the want there cams degreed to get more hp. I laugh and try to
explain but some article is the spoken truth.Thank you for putting it to words I myself am a DOer as you can tell by most of my post typing is not my skill.

 

[OB_Bob]

Thanks Brock
Sorry about the LSA comments did not mean to confuse anyone--yes separate cams allow you to adjust L.C.'s on the bike, all my motor work to date has been single cam V-8's so you need to decide upfront what you want.


I guess i will start the phone calls to Web and Yosh. Hopefully they have tech. reps that are knowledgeable. If something interesting comes from it i will post. Busa is still fairly new, which probably doesn't help with information or choices.
Bob

[This message has been edited by Bob (edited 31 December 1999).]

 

[OB_KawAbuser]

For the little it may be worth there is a UK company that makes a plug in box to the ecu harness to adjust the rev limiter, they currently make one for the late model GSXR750. If this is of interest I will in a little deeper.

Frank, Brock and Bob thank you!

Have a Happy New Year!

 

[OB_cbxchris]

Thanks Brock.....

 

[OB_Johnnycheese]

Thank you all, I had to print the page.
Like I said before I have a hard time explaning what y'll said.
Maybe more of my customers won't think I'm blowing smoke up there a--.
Thanks again and Happy New Year!

Johnny Cheese.

 

[OB_Dirty Pete]

Yes thanks Brock. Your back-to-basics info will help non-technical people like me make better decisions when it comes to aftermarket cams.

 

[Frank Adams]

Bottom line is...

If the Cam's are built to run (example) 100Hp, Thats all there going give you. No matter were you have them Degreed.

Degree or Advance your Cam's to move your power band around.

That all depends on what application your wanting to use.(Dragrace, Roadrace ect)

Look at your curves on your dyno sheets.

Thats like on My 1430 motor with the stock Cam's. This deal was just starting to build Hp when it hitting the rev-limiter. Because I had no way to advance the rev-limiter I had no way to know what the 1430's Hp capibilities really were.

To Me, The rev-limiter is the Biggest thing standing in the way for Hp.

On applications like Mine, reving past the stock rev-limiter is where the real hp is at!

Do You have a "FOR SURE CURE" for this?

I'm listening!

Frank

 

[OB_Bob]

Looks like the motorcycle industry keeps the cams a black art more than the Auto industry.

I have been building street / strip motors for cars for twenty years and never really messed with the bike motors much. Is information that hard to get from a cam company?
The majority of muscle car enthusiasts don't understand how to degree a cam or more importantly select one.
If you don't know, you better find someone you can trust or learn. Otherwise don't screw around with it. YOU need to decide what performance you want. Bigger is not necessarily better. Do you want a drag bike-high rpm power, no low end? Mild increase--A slight increase in power without sacrificing too much low end?
You primarily degree cams to move the power band -agreed, but when you swap to new cams and sprockets you degree them to insure their installed where you "want them". Your trying to insure that the sprocket co. and cam company manufactured the parts as stated. A little bit off in tolerance on the sprocket, and a little in the cam and your off. My last Ultradyne cam/timing gears was only off 1 degree, but it was off.
AS mentioned above, a cam is generally selected to peform within a certain rpm range (power band) This power band is determined by lift/duration, and lobe sep angle(can't change). Where you install it also affects where (i.e. 104 intake 105 exhaust). Compression should also be considered when selecting.

You also select the cam with airflow in mind. A wild high lift long duration cam may not work out if there are other limits in airflow--(head, valves, exhaust, rev limiter).

Anyway, I will be looking into cam swaps soon and I guess I will find out whats out there soon enough.
I would like to ask a couple questions though, and it seems like there are a few here that could answer them:

1. When comparing cams to one another what is the motorcycle accepted std. on duration? In other words 285 degrees duration at WHAT LIFT? .050? 1mm? Comparing cams at zero lift is generally bogus because cams can have different ramp profiles. Comparing two cams using different lift numbers is useless. Then we will need the stock cam specs?? for comparison. Until I know whats in it now, how can I change it.
2. Generally cam companies list cams by desired use (rpm range) Lobe sep angle generally determines the range of the powerband, tighter LSA means a more narrow power band and a larger LSA a broader power band. How does Web or ?? list them?

I would think the stock Busa (exhaust/PC2/airbox) would benefit from a little more lift/duration. Maybe a quicker ramp profile to open the valves sooner and a little longer. I would probably only look for a modest cam change keeping the power band usable all over. Those of you trying to Drag the bike only would want a bigger lift / duration cam installed to bring the power band up (7000+ rpm)
3. What are the stock cam specs??

I do know what the YOSH Stage 1 cams specs are thanks to Kawabuser. But, I don't know the stock cam specs??

For what its worth the Yosh specs:
INTAKE 244 degrees @ 1mm lift
9 mm max lift---102 degrees Lobe Center(102 is what you confirm with the degree wheel)
--(maybe the 285 degree number Frank mentioned is at zero lift for the stock cam?)
EXHAUST 230 degrees @ 1mm lift
7.8 mm max lift---105 degrees Lobe Center

3. Anyone have other specs from a different manufact? Or does everyone custom specify/grind

Bob

 

[OB_Brock Davidson]

Frank,
With a larger engine and stock cams,I would expect the power to fall off sooner.
Perhaps your ports are very large?

I have a cure for the rev limit on the busa.
Similar to the set up on my 750 .This is more for serious race applications. I hope that Yosh will distribute a plug-in black box, or dyno jet will allow for this in the power comander. Only time will tell.

Once you have the ability to rev higer, you must have springs that will not allow float at these revs. I find a way to use Yosh springs in all of my high-reving engines.
(I even have them in my wifes zx-11, 175 rwhp! shhhhhhhhhhh!!! )

Once again, hopefully Yosh will sell them soon.

I understand that KWS(843)566-0004 has some springs in stock that are working well with the Hot Street #483/536 Web cams.

Brock

ps Hey Guys,I appreciate the "thanks".
I belive that enthusiasts are entitled to "hassle-free" performance gains.(I sometimes feel that I am alone in the industry on this one!)Any idea how many people say "to hell with this" after a small dose of what Frank has gone thru?
I have always thought- the more people that stay interested- the better!

I don't mind giving out info if I think someone is listening.(definately alone in the industry!)

 

[OB_Cycle Stuff]

Thanks Brock, I hope no one else has to go through what Frank and I are going through to get a high performance street setup. I wish I was more mech. inclined to elaborate more about my 3mm project bike. Has anyone heard about a lockup yet?

Chucky

 

[Frank Adams]

Ok Brock, Heres My situation.

My Head is ported.

The dyno shows a rapid climb in Hp just before the rev-limiter.

I've talked with a few Busa builders that are saying Suzuki did thier home work on the stock valve springs. But only two have made mention of the stock retainers being bad.(loose/rubbing)
Jay Eshbach at Ape should have a cure for this next week.(Titainum replacements)

I agree about the Yosh Plug in Box.

Your Cure:
If I understand this right?
Everything still goes through the stock Ecm first. right?
If so, When the first box says it's rev-limiter time, What happens to the second one?

Another one, The stock Ecm has to get a ignition signal to control the other elements. Right?
In this case, How is it possible to split the rev signal to each box(stock/add on) and get the bike to perform properly?

NOTE! These are question that come from Me, My engine builder has His own theries.

I'm just looking for a DEPENDABLE SALUTION until as Brock says, Yosh or Dyno jet and the Power Commander comes up with something else.

ALL OPINIONS are EXCEPTED!!

....Frank

 

[Frank Adams]

Brock, This sounds like the system that I need to further My R&D on the Hayabusa.(getting closer!)

Can You Help?

Jay, I think on the 70-761 Cam's with the .050 the duration is more in the 240's.

But anyway, This is the Cam thats going to do the "Talking".

....Frank

 

[OB_Kong]

Brock, noticed you mentioned your wife had a 175 rwhp ZX11. Can you tell me whats it got, is it still a good street bike motor, thanks

 

[OB_Brock Davidson]

Kong,
The standard stuff:
Yosh(GSXR) valve springs, my custom titanium retainers, custom pistons (my design from blanks ,79mm total seal rings), custom crank work (lightened stroker,carrillo rods, cryo-treated), custom valves (from ferrea blanks on intake, modified gsxr intake on the exhaust)Web cams, R&D tranny, bored out 41 Kehin carbs.

It ran great untill one of the stock oil lines burst and toasted the crank!( Ever try to repair a custom engine like this? Takes FOREVER and requires bank robery!!)

Cost? One Million Dollars(in Dr. Evil tone!)
Hastle factor.....off the scale!

Makes me realize how awsome these Busas are!

Brock

I sure do hope the new 12R has room to grow. If not...the Kaws will STILL not be able to hang in the FAST streetbike world.

 

[Guest]

Brock, I would like to ask your opinion on a subject of great importance to me. Cost being no object and without any geographical limitations, who in your opinion is or are the best in the business at honda motors. I have chosen erion racing to assist me in getting some additional horses out of the 2000 XX I just purchased. Am I where I need to be or could I do better?

 

[OB_Jay]

Web is listing 2 grinds for the Hayabusa.
#70-751 is .378" intake and .330" exhaust lift, with durations of 267 and 242 ( I believe those are .030" numbers.

#70-761 is .395" intake and .378 exhaust lifts with 266 and 267° duration.

I have the .050 numbers at the office.

Jay

 

[OB_DanaT]

Does anyone number the serial numbers that have the good cams? Where the 'good' cams the early or late bikes?

I have number 1135. What cams would this bike have?

Thanks
-Dana