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CVO Technical => Twin Cam => Topic started by: ltank on November 28, 2018, 06:48:53 PM
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What's the best midrange cam for 124 motors? I ride at 3200 most of the time. What about the S&S 625 that has a 55 degrees intake valve close. The 585 cam closes at 45 but is sluggish on a big motor.
Doesn't have the Pep that I like. Thanks
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I wouldn’t use the 625 it has to much exhaust my choice would be 585 or more compression and 640. Something seems astray if the 585 is sluggish (expect it is your pipe it’s too big for your build).
The group of them we have down here jump out real quick and in stock trim are delivering 134-142 torque and 118 to 128 HP
With the light compression it will be imo tough to get what your after at 10 to 1 Have to make trade offs. Without a Dyno you have no real way of gauging your a/f other that what you think is happening. You might consider a Wego or other device to see where your A/F is actually at.
What do your plugs look like? Have seen this exact scenario with another RB pipe on a 124. Shannon finally relented, he put a thunderheader on it and couldn’t be happier. My opinion is your pipe is hurting you where you want the power. I’d try a smaller pipe before I’d change the cams. Maybe someone has one u could borrow just for a test?
Hope ya figure it out.
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The S&S V124 I have used the same pistons as the
T124LC and 585 cam. I talked to S&S all the other parts are same. Heads, rocker rollers, Super G carb.
Only difference was the cam and pistons. The 600 has. 25 less lift, all other is same. The 585 is torque low end cam, the 600 is midrange cam the 640 is a mid/ top end cam. So the 600 should be fine for touring. I will see! Thanks guys.
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I ordered some used staggered dual pipes with smaller 1 7/8" head pipes with 2" ends with baffles.
If that works I can take it from there. Gonna try the 600 cam too. To me I prefer the sound of two pipes
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625 straight up is kind of a dud
Advanced 4 degrees at 10.8-11-1 works pretty well
What's the static compression of the engine now?
10:1?
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look at the T MAN .625
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The Tman 590 at a conservative 10.4 or 660PS2 at 10.8
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look at the T MAN .625
If you have a conventional cam chest, not the s&s, and you have compression releases, then the 625 T-man or the new 585 T-man, at 10.4-5 will be just what you're looking for
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Others, lower lift
Kuryakyn 24D
TTS 150
Both won't need big compression but will be good manered, easy on valve train, and easy to tune
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I’m running a tman 590 in a 117 at 10.7 to one and it runs cool and pulls from 2500 and doesn’t quit till redline.
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I’m running a tman 590 in a 117 at 10.7 to one and it runs cool and pulls from 2500 and doesn’t quit till redline.
t man 590 is a very good choice.set @ 10.8-1,or like I said earlier,t man 625 set @10.25-1
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But the 585 is a decent choice for what you describe.
Use it. A stock crate 124 work perfect there.
Eyeball should be on motor health (compression test/leakdown), tune and pipe.
Listen to unbalanced, he provides real world
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TMan 590s work well in those motors with some head work and a valve job that compliments them.
Flat TQ (130/130 from 110s at 10.5 is pretty standard. Intake close is just one parameter, the overlap
is a little more important imo, and 55* close is kinda working against you in the "midrange" department.
Stock heads hold you back allot as well, the short side is too abrupt and the bowls need help.
You'd be way ahead of the fame by making the heads work better and staying conservative on the cam.
No amount of cam can truly compensate for a bad head. You can band-aid some port issues
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But the 585 is a decent choice for what you describe.
Use it. A stock crate 124 work perfect there.
Eyeball should be on motor health (compression test/leakdown), tune and pipe.
Listen to unbalanced, he provides real world
S&S 585`s are a great cam and use them a lot in different builds,but wouldn't be my first (or second) choice for good midrange on a 124",much better choices out there
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My go to for mid is the 662-2. It likes 11:2-3 static but with 50 closing. It’s only static.
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My go to for mid is the 662-2. It likes 11:2-3 static but with 50 closing. It’s only static.
That's a good one as well, decent midrange on a 124.
Static. People like to cling onto static (cranking numbers), which is fine when discussing
starting the engine. After its running, that goes out the window to a large extent.
Even though the intake runners are horrible on these engines, air momentum in the
intake tract will overcome some of that 'late close' as RPM increases.
a 124 should have allot of grunt, no matter what you do to it. (Even if you pick a crap
cam, it's still gonna have grunt).
The cam should be selected after you know what the heads flow.... that's JMO.
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We're working on making a better intake manifold. It's going to be a challenge but we'll come up
with something pretty decent.
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a 124 should have allot of grunt, no matter what you do to it. (Even if you pick a crap
cam, it's still gonna have grunt).
Agreed, something is wrong and eyes should be on motor health, pipe, and tune before playing musical cams
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My experience with a 662-2 is not a good midrange cam . A good top end cam.
BigLew
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a 124 should have allot of grunt, no matter what you do to it. (Even if you pick a crap
cam, it's still gonna have grunt).
Agreed, something is wrong and eyes should be on motor health, pipe, and tune before playing musical cams
There's a prevailing tendency out there for people to blame the cams. If you select a cam set based on the
airflow of the head and intended use (RPM/displacement) of the motor, it becomes pretty straight forward.
The pipe and tune often take a back seat in these situations. People are quick to condemn the cams
when things don't turn out right. More often than not, it's not the cam. It's a mismatch of components.
I agree with that statement, pipe and tune must match the rest of the build or you're wasting money and
time.
The pipe is critical, and it's often overlooked from a performance standpoint.
(Selecting a pipe based on looks, sound or some uneducated guess is not a winning strategy. The intake
manifold is also critical. But the choices are limited b/c the of the design of these motors, they don't lend
themselves well to getting creative with a manifold.
We're using some CFD models to come up with something that's "tuned" for the engine. Getting something
that physically fits in there is going to be a challenge.
If looks and sound are more important, then by all means, go that route. But don't expect miracles from
a well thought out build with a less than ideal pipe).
Looks and sound are not even on my radar screen
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My experience with a 662-2 is not a good midrange cam . A good top end cam.
BigLew
If the motor is big enough, and/or the bike is light enough, it could be a great midrange cam. :vrolijk_24:
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The manifold needs to be 3d printed and hopefully made of a material that is not a good heat conductor.
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The manifold needs to be 3d printed and hopefully made of a material that is not a good heat conductor.
I'm still in the design/development stage. Making it fit on the bike is going to be the biggest challenge.
first one is going to be CNCed billet aluminum
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We're working on making a better intake manifold. It's going to be a challenge but we'll come up
with something pretty decent.
Space is at a premium, be interesting to see what you come up with.