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Discussion Starter #1
I've got a little project in mind, and I have no experience with designing or making camshafts.
 

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I've got a little project in mind, and I have no experience with designing or making camshafts.
design is easy, its the mfg process tht kills it, not many machine shops are willing to do them due to the tolerances required
 

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cam shafts are best left to the pros. I work with cad 50 hours a week and i wouldn't think about doing a cam. That is something that takes years to get good at. If you want a custom cam then call up a race shop that makes them and start there.
 

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I agree with the above two posts. A race shop is your best bet.

But usually you get some camshafts and the lobes are hardwelded and reground to the profiles you want. I guess some racers have some pretty radical lobe profiles I'm told.

Anyway, I think there are specialty machines dedicated solely to grinding camshafts - not something your run-of-the-mill machine shop will have.
 

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Maybe try APE out in California...
or Webcam out in Riverside...
or megacycle out on the east coast...
there are probably plenty of places. Expect to spend about $400 (I'm guessing for two cams...).
 
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Yeah, I know all of the above. I'm just looking to get a jump on getting things designed for the project so I can figure out the rest of the changes. Everything else is electronic, but all depends on how the camshaft will work.
 
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is the project top secret???
Nope.

I love the torque and power delivery of twins, but love the agility and balance of the 600RR. Screamer engines are nice, but big bang engines are even better (The R1 has an irregular firing order, so don't mention that bike).

Custom cam shaft to open the intake and exhaust ports at the same time on cylinders 1 and 4, and 2 and 3. Reworking the ignition firing order, and injector firing order. Cuts down on rev pick-up, but that is easily made up for with lightened parts, and overall peak HP will be lower, but the torque will be increased a ton and the overall power delivery will be smooth as butter. Also makes sliding the rear easier to deal with, and my riding style gets the rear loose a bunch.
 

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if you have the brain to understand and get it to work, and the money to do it go for it.

But i wanna hear and see the before and after
 

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damn...somebodies done their homework lol... sounds pretty cool man.. kind of getting the best of both worlds eh?
 
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Discussion Starter #11 (Edited)
damn...somebodies done their homework lol... sounds pretty cool man.. kind of getting the best of both worlds eh?
Somewhat. People have done it to older gixxer 750's and 1000's, but it's far easier on those since it takes nothing special to hack the stock ECU.

Here's an 01 R6 changed from a screamer to a big bang. Don't know why they did that to a carbed bike, because as you can see, they're hard as **** to start up without FI.

The R1 has the irregular firing order, and how the power is delivered explains why they eat up tires.
 

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its not all about where the bangs happen.

A lot of the low end torque from a V-twin or a cross plane inline four comes from always having a piston at full velocity while the other is stopped (in a four cylinder 2 are stopped at BDC and TDC while too are full speed at mid stroke).

this means that the weight of the pistons helps contribute to the momentum of the system, where as in a traditional 180 degree crank shaft all 4 pistons come to a dead stop, then must be started again, all the inertia to keep the engine spinning must come from the crank shaft and fly-wheel. in short this is bad for power and drive grip.

BUT...

Another aspect of engine design and tuning is acoustic properties, the pressure waves inside the intake runners and air box (and exhaust) caused by the intake valve opening and closing can be used to the engines advantage by timing the high pressure portion of the wave with the intake valve opening, helping force air into the cylinder. The length of the runners and the size of the air box can be selected so that this effect is maximized at a certain RPM.

uneven firing order i4's and v-twins have pour acoustic properties because the waves inside the air box are not regular because the engine sends out a bunch of waves in a short period of time (well not really time, but crank angle) then is silent for a long time (again, more in terms of crank angle). which is why the new R1 has poor top end power when compared to the traditional engine configurations in other i4 liter bikes.


I am far from an expert in this field, but trust me when I tell you changing the firing order on your well running RR will be a world class head ache that best case scenario will give you mediocre results.
 
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its not all about where the bangs happen.

A lot of the low end torque from a V-twin or a cross plane inline four comes from always having a piston at full velocity while the other is stopped (in a four cylinder 2 are stopped at BDC and TDC while too are full speed at mid stroke).

this means that the weight of the pistons helps contribute to the momentum of the system, where as in a traditional 180 degree crank shaft all 4 pistons come to a dead stop, then must be started again, all the inertia to keep the engine spinning must come from the crank shaft and fly-wheel. in short this is bad for power and drive grip.

BUT...

Another aspect of engine design and tuning is acoustic properties, the pressure waves inside the intake runners and air box (and exhaust) caused by the intake valve opening and closing can be used to the engines advantage by timing the high pressure portion of the wave with the intake valve opening, helping force air into the cylinder. The length of the runners and the size of the air box can be selected so that this effect is maximized at a certain RPM.

uneven firing order i4's and v-twins have pour acoustic properties because the waves inside the air box are not regular because the engine sends out a bunch of waves in a short period of time (well not really time, but crank angle) then is silent for a long time (again, more in terms of crank angle). which is why the new R1 has poor top end power when compared to the traditional engine configurations in other i4 liter bikes.


I am far from an expert in this field, but trust me when I tell you changing the firing order on your well running RR will be a world class head ache that best case scenario will give you mediocre results.
When you get everything else to work with it, there's no problems to really be had. Hell, Ducati can change their V4's firing order at will with just swapping some electronics and the camshafts.

Though, this isn't going to be intended as a project to gain HP or anything.
 

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give these blokes a go, tell them what you want and they will build it, even down to what flow rates you will get through the valve train for the timing events your after.

http://www.surecam.com.au/

Although I would be a little concerned with the extra stress you will be putting through the crankshaft at higher rpm given that you will be firing two cylinders at once.

I think the simple part will be getting the FI system to do its job, all you have to do is ensure the ecu will sink the current required to drive two injectors and coils at the same time, if it wont then it is a simple thing to fix, however that will affect the timing events.
 
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Getting the FI system will be the hardest for me. I ******* hate electronics.

Camshaft wont be stock so I wont have to worry about added stresses. If I ever have the money to do it, it'll be as a full superstock build.
 
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Eh? How about the crank?
Crankshaft doesn't need to be changed out unless you're running an irregular firing order, like what only Yamaha uses. Big bang and standard firing engines run off of the same crank design, just different fuel/ignition controls and different cam shafts.

Piston timing stays the same between big bang and standard firing orders.
 

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So on a normal firing order, while one cylinder is TDC and firing, the other one at TDC exhausting and about to intake? Then the other two come up and do the same thing?

And you want to change it so that at TDC they are both in sync with each other?

Hopefully that makes sense to you. I'm pretty sure I get the concept
 
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