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GPracer2500
06-11-2006, 12:25 AM
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I see a lot of questions about 400EX cams. I thought it might be helpful to have a list of many of the available cams with their specifications. I picked up these specs from various places...if anyone sees errors point them out. The Hotcams specs are straight off their website and I called them to get the specs for the old version of the stg 2.

I won't comment on brand X vs. brand Y because I'm not qualified to do so. Also, I can't really comment on how cam X will perform in your quad because in most cases I don't specifically know that information. Instead, I've tried to put together some technical information that might help YOU decide what cam might suit you and your engine.



On to the specs!!

cam: Intake lift; Exhaust lift; Intake duration; Exhaust duration

stock............... .316, .302, 234, 238

XR400.............. .326, .321, 240, 244
HRC................. .350, .339, 254, 256
GT Thunder....... .350, .345, 256, 256
WB Track.......... .350, .345, 256, 256
WB All Around.... .345, .335, 240, 248
WEB 450/451..... .350, .345, 256, 256
WEB 479........... .378, .378, 250, 250
WEB 463/9i....... .385, .370, 272, 270
Hotcams stg 1... .354, .354, 246, 246------Intake centerline 106, Exhaust centerline 107
Hotcams stg 2... .354, .350, 254, 248.5----Intake centerline 106, Exhaust centerline 104.25
HC stg 2 (old).... .348, .349, 254, 254------Intake centerline 106, Exhaust centerline 107
Hotcams stroker. .358, .354, 262, 257------Intake centerline 110.5, Exhaust centerline 104.5
Megacycle x1..... .346, .346, 246, 246
Megacycle X2..... .378, .378, 254, 254
Megacycle X6..... .402, .385, 270, 262

Notes:

--Numbers are listed in inches and degrees of crank rotation (lift duration at approximately .050" lift).
--The Hotcams stg 2 old version is identified by "HCDG NO. 08" etched onto the cam--not sure what the current version says. Hotcams part number for the old cam is 1008-2.
--Valve clearance specs for all Hotcam cams are: intake .005", exhaust .006"
--White Brothers All Around is etched with "WB1870".
--White Brothers Track is etched with "WB1498".
--Notice that the WEB 450/451, GT Thunder, and WB Track are all the same grind.
--Honda part number for the HRC cam (it's actually an XR400 HRC cam) is 14000-NKK-000. I don't [i]think they are still available from Honda.
--Some retailers list a Hotcams Stage 3. This is an sometimes an erroneous label given to the "old" version of the Stage 2. Some retailers have stock on both the "old" and "new" versions and have to call the "old" version something, I guess. Other times the "stage 3" label is given to the stroker cam. So just be careful concerning the the "stg 3" label cause it could mean different things.
--This is what Hotcams told me about the performance difference between the "old" and "new" versions: "...As far as the difference between the old stage 2, and the new stage 2, the new stage two still has a good top end gain, but doesn't loose as much on the bottom..."



The lift is how far the cam opens the valve. The duration is how long it leaves it open. The more lift and duration the more aggressive the cam. Big lift and duration numbers work best at high RPM while more mild numbers are best for lower RPM.

The more duration the intake valves have the more important it is to have a high(er) compression piston. This is because with lots of duration there is more opportunity for air to escape through the valves as the piston begins its compression stroke. Even on the stock cam, the intake valves are still open when the piston begins its compression stroke. With an aggressive cam some dynamic compression is lost through valves that stay open for a long time. This must be made up for with a higher compression piston. An aggressive cam with a stock compression piston may actually perform worse than the stock cam because too much compression is being lost through the valves being opened so much. I have personally seen this happen--dyno confirmed (although it wasn't a 400EX).

Here's a theoretical example to help in understanding this concept:

-bore: 85mm (stock)
-static compression ratio: 9.1:1 (stock)
-elevation: 1500ft
-intake valve closes: 40deg ABDC (After Bottom Dead Center) (stock at 1mm lift)

The resulting dynamic compression ratio is 8:1. Note that is a smaller figure than the static compression ratio we started with. Again, this is because the actual compression of the compression stroke doesn't really start until the intake valves close.

Now, if we increase the intake valve duration to 55deg ABDC and leave the static compression ratio at 9.1:1, we get a new dynamic compression ratio of 7.4:1! In order to get the dynamic compression ratio back to where we started (8:1) with the increased intake valve duration we would need a piston with almost 10:1 static compression. Just for the heck of it I looked at how 5500 ft of elevation changes things. At 5500ft with the 55deg ABDC spec you'd need a 10.8:1 static compression piston to yeild an 8:1 dynamic compression ratio.

Now, you might be thinking what's the point of adding a cam and a piston if doing both gets you the same dynamic compression ratio you started with?? Good question. The answer is that now you have the same dyanmic compression ratio you started with but also have the cam specs that will allow the engine to breath better. And in the real world, most piston choices are actually going to bump your dynamic compression beyond what it was stock even with the addition of a cam. A 10.5:1 piston with a cam (using the 55deg ABDC spec) would get you a dynamic compression ratio of 8.6:1--0.6 points higher than all stock.

I used a dynamic compression ratio calculator to get those figures. I guessed on certain required values because there's some information I don't have. So, the above numbers are not quantitatively exact. But the relationship between static compression, dynamic compression, and intake valve timing IS accurate.



Knowledge is HorsePower!

JOEX
06-11-2006, 10:30 PM
Thanks for consolidating this info GPracer:)

Can you elaborate a bit on Duration and Lift and how they affect performance? i.e. How a relativly higher lift/shorter duration cam performes differently than a lower lift/longer duration cam.

I'm not sure if this applies to the 400ex and similar motors though....

GPracer2500
06-12-2006, 03:18 AM
Originally posted by JOEX
Thanks for consolidating this info GPracer:)

Can you elaborate a bit on Duration and Lift and how they affect performance? i.e. How a relativly higher lift/shorter duration cam performes differently than a lower lift/longer duration cam.

I'm not sure if this applies to the 400ex and similar motors though....

I'll try and answer with my current level of understanding:

Increasing lift without increasing duration will normally yield more power throughout the RPM range. However, an increase in lift is almost always accompanied by an increase in duration.

Lift and duration generally go up and down together because of practical limits governing the shape of the lobes. If you tried to have super high lift with moderate duration than the lobes would become prohibitively "pointy"--very tall but narrow. The ramps of the lobe (ramps are the transition zones on the sides of the lobe) can only be so steep for reliable valvetrain operation.

Specific to intake valves, there is a limit to the speed of the intake charge before effiecency begins to drop off. That natural "speed limit" for the intake charge helps do define the lower limit of possible lift specifications for any given duration. Long duration with moderate lift would leave you with very high intake charge speeds. Go too fast and you start going backwards. That doesn't apply to the exhaust gases exiting the exhaust valves though. I'm not sure why.

I hope that at least partially answers your question. I'm gonna stop there because I'm starting to get in over my head--I'm no expert on these matters.

ETA: Actually, I probably should have stopped before I started...really, I'm an amature. I'd much rather we got answers from an expert.

Choppers
06-20-2006, 04:55 PM
you should sticky this. so many people ask about this.

Choppers
06-20-2006, 07:12 PM
Messed up

GPracer2500
06-26-2006, 03:47 AM
I wonder if this info is really helping the average joe make a choice. I feel like something is missing--but I'm not sure what. :ermm:

Where does valve overlap fit into this? Why don't cam manufactures publish overlap data? Is there away to evaluate the most efficient RPM (peak torque) for a camshaft from lift/duration numbers alone?

Are there any engine builders that could enlighten us?

PowerJunkie
06-28-2006, 03:07 PM
so how do you know what is the best rise heigth?

GPracer2500
06-28-2006, 04:21 PM
Originally posted by PowerJunkie
so how do you know what is the best rise heigth?

To the best of my understanding, it depends on how the rest of the engine is configured (porting, bore, compression ratio, etc.) and where you want the engine's power to be concentrated (low rpm vs. high rpm).

I realize that answer may not help you make a decision. But when I try and elaborate more than I already have in the original post, I start becoming unsure of the accuracy of my advice...

07-22-2006, 12:03 PM
do have any specs on the magnum cam

GPracer2500
07-22-2006, 12:39 PM
Originally posted by pimpin416ex
do have any specs on the magnum cam

I've looked and can't find squat. Last time I looked I couldn't even find a website for the manufacture....:ermm:

07-22-2006, 05:39 PM
ok thanx

EXevan91
07-24-2006, 10:47 AM
the magnum seens to have long duration and i meen alot. i have one and i scompared to stock and lots more duration

GPracer2500
08-20-2006, 09:35 PM
I see a lot of discussion about the HC stage 2 vs. the HC stage 1 for a stock compression engine. I've done some calculations to define how much the stage 2 might hurt bottom end performance. If you read the entire first post then you know that the issue is the loss of compression from the intake valves staying open a long(er) time. Compression is a dominating factor for producing low end torque. Here's the difference:

Taking into account the valve specifications:

Stock cam cranking compression at 1000ft = 8.2:1
HC stage 1 cranking compression at 1000ft = 7.8:1
HC stage 2 cranking compression at 1000ft = 7.6:1

If you go to a 11.0:1 piston (instead of the stock 9.1:1 piston) then the numbers change to:

stock cam: 9.9:1
HC stg 1: 9.5:1
HC stg 2: 9.2:1

(figures may not be absolute but the comparison is accurate)

kennymac131
09-02-2006, 11:37 AM
Does anyone know where to get the white bros. all around cam for a good price? I live in Mesa, AZ and I would assume that local dealers 1) would be expensive and 2) would have to order it. So I'm willing to go mail order.

Any help is appreciated.

Does anyone use this cam? What are your thoughts?

wilkin250r
09-02-2006, 08:08 PM
While extremely informative, I'm sure some people are a bit confused on what the numbers MEAN, and also what the numbers DON'T tell you.

As GPRacer said in the third post, higher lift generally means more power. The valve is actually open more, so the engine breathes better. But it's not always possible to increase lift without increasing duration.

As a general rule, more duration will have more top-end power in higher revs, but less low-end power.

wilkin250r
09-02-2006, 08:24 PM
Now let's talk about what the specs DON'T tell you.

What is duration? It's a measurement of how long (in crankshaft degrees) the valves are open. But an important aspect is the definition of "open". If the valve is lifted .001 inches (about half the thickness of a piece of paper), it's not really "open" because you don't get any meaningful amount of airflow through such a small opening. So cam manufacturers define "open" when the valve is lifted at either 1mm (about 0.040"), or 0.050". Both are standard, it just depends whether you're using a metric system or not, but they don't always tell you which one they measure to. YOU need to be aware of the issue because that difference of 0.010" can change your specs by a degree or two. You may wish to talk to the manufacturers to get all the information.

wilkin250r
09-02-2006, 08:41 PM
The specs also don't say anything about overlap, and it can be extremely important. Overlap is the amount of time (in crankshaft degrees) that both intake and exhaust valves are open.

Overlap is critical because air has mass, and therefore has inertia. It doesn't move instantly, and it doesn't stop instantly. Both are important.

When the exhaust valves open, the exhaust gasses go rushing out, and the piston begins it's upstroke. The piston gets near finishing the exhaust stroke, and the intake valves open before the exhaust valves close. Why?

You have exhaust gasses moving OUT, and they have their own inertia. Meanwhile, the air sitting in the intake also has inertia sitting still, and it takes energy and time to get that air moving. Wouldn't it be great to use the inertia of the exhaust going out to help kick-start the intake process? This is exactly what overlap does. Because both intake and exhaust are open during overlap, it takes advantage of the inertia of the exhaust gasses to pull a vacuum inside the cylinder, and that vacuum will help get the air moving inside the intake. This means that you can actually begin the filling process BEFORE the piston begins it's downstroke. This is called scavenging.

On a related note, the intake duration actually extends past BDC, because of the inertia of the incoming air. The air is already moving, and doesn't stop instantly. That can be used to stuff the cylinder even after the piston begins it's upstroke, like a super-charging effect.

Now, this stuff happens at high RPM, when air is moving the fastest and thus has the greatest momentum. But what happens if that momentum didn't exist? When the piston begins it's downward stroke, it would pull in air from both the intake AND exhaust, because the exhaust wouldn't have that outgoing momentum and would be free to reverse. Obviously the exhaust won't burn a second time, so any space it takes up is lost power. Likewise, if the intake valves are open after the piston begins it's compression stroke, you certainly wouldn't super-charge the cylinder, you would force a little bit of air OUT, back into the intake. This not only results in lost power, but it would pass through the carb again, and get mixed with more fuel and result in a double-rich mixture.

This is exactly what happens at low RPMs. Without that velocity, the air doesn't have momentum. This is why camshafts designed for high-rev have very poor performance at low RPMs and rough idle. The exact same things that are beneficial at high rpms will cause problems at low rpms.

This is also related to head porting. This is why bigger isn't always better, because the key is VELOCITY, not AMOUNT. Although a larger port might be able to flow a larger AMOUNT, it may have a lower VELOCITY, and that velocity is very important to your scavenging and supercharging effects.

GPracer2500
01-17-2007, 09:45 AM
Some info from a recent thread that I thought belonged here too:

Regarding the various Hotcams cams, there are four different cams.

A few years ago 1043-2 replaced 1008-2 as the stg 2 and the "Stroker" cam was released. Hotcams has since dropped the "Stroker" label and now calls that cam Stg 3. But sometimes the old stg 2 (1008-2) is called a stg 3. :confused: Some of the Hotcams "stage" labels are ambiguous. It's better to use the HC part numbers to possitively identify.

1007-1: Stage 1, always has been.
1008-2: The original stage 2. Sometimes called "old stg 2" and sometimes called stg 3. No longer being manufactured.
1043-2: The current stg 2. Replaced the 1008-2.
1051-3: The current stg 3. Use to be called the "Stroker" cam by Hotcams.

Got it? Good. ;)

cam: Intake lift; Exhaust lift; Intake duration; Exhaust duration

1007-1... .354, .354, 246, 246------Intake centerline 106, Exhaust centerline 107
1043-2... .354, .350, 254, 248.5----Intake centerline 106, Exhaust centerline 104.25
1008-2... .348, .349, 254, 254------Intake centerline 106, Exhaust centerline 107
1051-3... .358, .354, 262, 257------Intake centerline 110.5, Exhaust centerline 104.5

Those are the 4 Hotcams cams for the 400EX. It's no wonder some manufactures just stick with numbered names instead of "stages".

hypersnyper6947
05-31-2008, 12:01 PM
I have the 1043-2 and with my mods im wondering if i should get the old stage 2 or a stage 1. Will this work well for my 440 11:1, i already have just have not installed it yet.

tri5ron
04-06-2009, 12:20 PM
Bump.
(Just because I had not seen it up for a while).

Ryan'07400ex
05-01-2009, 05:55 PM
Sticky?

Js7bla
05-11-2009, 08:20 AM
If anyone could help me i would sure appreicate it, i am looking for a cam for my 2000 400ex, i have a std bore je 12:1 comp piston in it, a full curtis sparks exhaust, stage 3 rev box, i am lookin for a cam that is mostly bottom end and mid range, i been lookin at the hotcams but they say mid to top range and im wanting bottom and mid, can some 1 please help me, any suggestions? Thanks

2001400exer
06-01-2009, 01:46 PM
Originally posted by Js7bla
If anyone could help me i would sure appreicate it, i am looking for a cam for my 2000 400ex, i have a std bore je 12:1 comp piston in it, a full curtis sparks exhaust, stage 3 rev box, i am lookin for a cam that is mostly bottom end and mid range, i been lookin at the hotcams but they say mid to top range and im wanting bottom and mid, can some 1 please help me, any suggestions? Thanks

what they mean by mid and top is added mid and top over the stock cam
the best way to get an idea of how a camshaft will effect your motor is by looking at duration, typical added duration provides an earlier intake opening point and a later intake closing point therfore adding more duration (or time the valve is open) to the cam. BUT there are other factors that truely determan the power range the cam is going to work in. example: because i mostly build raptor 660's i will give an example of two cams that look identical based off lift and duration but will perform totaly different
the X3 is a 276 intake duration and 274 exhaust duration
the X4 is a 276 intake duration and 274 exhaust duration
both cams have identical duration and lift but the X3 has and earlier intake opening point and and earlier intake closing point making up the 276 duration and the x4 has a later intake opening point and a later intake closing point
X3 Intake open 36 BTDC Intake close 60 ABDC
X4 intake open 30 BTDC intake close 66 ABDC
so even though duration might be the same actualy performance of the cam and power range is based off of overall duration, intake closing point, LSA (lobe seperation angle), and overlap...so when comparing two cam like the X3 and X4 the different opening and closing points of the cam determain the total amount of duration, lsa, and overlap a cam has the
X3 has more overlap and a tighter LSA
where as the X4 has less overlap and a wider LSA so they will performe differently and are designed for two different engine profiles the X3 is more of a stroker style cam where as the X4 works better in a big bore high rpm engine
anyways back to the 400ex and a list of duration and in general the given rpm range where the cam will make its best power
210-220= 1000-5200rpm
220-230= 1500-5700rpm
230-240= 2000-6200rpm
240-250= 2500-6700rpm
250-260= 3000-7200rpm
260-270= 3500-7700rpm
270-280= 4000-8200rpm
280-290= 4500-8700rpm
typicaly for every 10 degrees duration you move the power band up 500 rpm but if you have a degreeable cam sprocket, taking any given cam and advancing/retarding the timing by 4 degrees will move the powerband up or down 300-400 rpm
advancing the cam timing will move the powerband lower where as retarding the cam timing will move the powerband higher
i would look into a stage two or even stage 3 hotcam for your set up, even a stage 3 with 262 duration falls into a solid midrange engine if you figure with your rev box adding rpm and being set at lets say 10500 rpm then a stage 3 cam is pretty well in the middle, also with a later intake closing point you will bleed off alittle more compression and you should be able to run high octane pump gas in that 12:1 engine, and odds are if you have 12:1 in your set up now with a stock cam, i would say your jetting is rich because you should be getting knock if you run it on pump gas, and if you run race gas i wouldnt run straight race gas (depending on what octane it is) you will be fine with about 98 octane so (like me) if you have 110 available at the pump, mix it 50/50 with 87 ctane this will take that 110 down to 98.5 octane and with the added lead in the 110 you should have no problem with heat in the motor...this is just my opinion based on the knowledge i have

Ryan'07400ex
06-06-2009, 09:29 AM
Originally posted by GPracer2500
I see a lot of discussion about the HC stage 2 vs. the HC stage 1 for a stock compression engine. I've done some calculations to define how much the stage 2 might hurt bottom end performance. If you read the entire first post then you know that the issue is the loss of compression from the intake valves staying open a long(er) time. Compression is a dominating factor for producing low end torque. Here's the difference:

Taking into account the valve specifications:

Stock cam cranking compression at 1000ft = 8.2:1
HC stage 1 cranking compression at 1000ft = 7.8:1
HC stage 2 cranking compression at 1000ft = 7.6:1

If you go to a 11.0:1 piston (instead of the stock 9.1:1 piston) then the numbers change to:

stock cam: 9.9:1
HC stg 1: 9.5:1
HC stg 2: 9.2:1

(figures may not be absolute but the comparison is accurate)

To me this says that the stock cam is better because don't you want higher compresion? Or with less compression you get higher top speed?

2001400exer
06-06-2009, 10:25 AM
i guess i really didnt get into static compression and dynamic compression

compression is only one peice of the puzzle in building a big HP motor
yes when you put in a bigger cam with a stock piston or any piston for that matter, the compression will drop with a bigger cam vs. a smaller cam
this is known as static compression (if the intake valve closes at BDC), and dynamic compression (because the intake valve closes how many ever degrees after BDC based on the cam profile)
BUT you have a window of peformance here, typicaly you do not want your dynamic compression to fall much below the 7.5:1 mark, some may argue with this compression ratio but once you hit that mark your cranking compression starts to fall beyond the usuable mark, this is why the higher compression piston is needed, im pretty sure i stated it before and i will state it again, just because you have a 12:1 piston in your engine does not mean you need to run high octane race fuel, but most do because they like to say they have to run it...blah blah, what they dont know is that they are losing power because the fuel actualy burns slower, and depending on the ignition curve they probably wont actualy burn as much in a cycle as what they would with a lower octane,
as long as you stick to 200 give or take 10 psi on cranking compression you will be just fine on 93 octane, and higher and its time to start uping the octane rating but just because you cant run 93 doesnt mean you have to dedicate your engine to 110, start mixing the two and get a more usuable octane. and i will say this for everyone out there with a cam and high compression engine NONE of you need 110, 110 is stable for about 300 psi cranking which equates to arround 13.25 DYNAMIC compression so for any of you thinking you may be close well you would need 15:1 piston with a stock cam, so for all you running 110 really its not needed and you are wasting your money but just beware of your dynamic and cranking pressure
back to the high compression low compression and rpms
high compression will always make more power and torque across the board when compared to lower compression but typicaly you see the bigger gains made in the lower rpm range when you are "off" the cam, high compression will also always give more snap when tuned right over a lower compression piston
some people do run the stage two cam with the stock piston which is ok, but you may not be happy with the results of going to this cam unless it is with an 11:1 or so piston to bring the dynamic compression back up
well i hope i coverd a few more things for some people

odog
10-26-2009, 05:28 PM
im just wondering with my setup 11.1 piston should i keep the stage 3 hotcam or get another cam i have plenty of bottom end power i mean plenty 1-3rd but i wouldnt mine having a little bit more on the top end what do u guys think.

papasmurf660
11-13-2009, 11:15 AM
I have a Motor I took the cam out of and I am not sure if it is stock or not. It came out of a 440. I just am not sure if it is stock. There is some scribing on it. I think it is 81HT...but I am not sure. I tried to get PICs of the scribe but they won't come out. If you guys can help....thanks!!

siggy konowaluk
12-07-2009, 07:38 PM
can you put a 450r cam in?

440exhondaman99
03-08-2010, 12:00 AM
Originally posted by papasmurf660
I have a Motor I took the cam out of and I am not sure if it is stock or not. It came out of a 440. I just am not sure if it is stock. There is some scribing on it. I think it is 81HT...but I am not sure. I tried to get PICs of the scribe but they won't come out. If you guys can help....thanks!!


that is deflently not a stock cam... it doesnt have the compreshion release on it that comes on the stock cam... i cant say what it may be but i know it aint stock

400exmxrider15
02-11-2011, 04:25 AM
Read through this whole thread and couldn't find any info about whats best for the type of riding you do. I was just wondering, but i race MX, and I have always been curious as to which cam is best for MX...Someone give me some info please. thanks Mods are in my signature.

250rforlife
02-11-2011, 07:18 PM
ok i understand 3/4ths of it. but the dynamic and static comprestion. i wanna no what each one means.and witch on is the one that makes u have to run race gas or not.

wilkin250r
02-11-2011, 08:46 PM
Originally posted by 250rforlife
ok i understand 3/4ths of it. but the dynamic and static comprestion. i wanna no what each one means.and witch on is the one that makes u have to run race gas or not.

Simple explanation. First off, we're not talking about compression readings, we're talking about the actual calculations.

The compression ratio as you normally see it, like 9.4:1, is the STATIC compression ratio. Let's make up easy numbers. The "size" of the engine is the actually volume the piston moves, let's say it's 360cc. Let's also pretend this engine has a 40cc combustion chamber (the volume of space when the piston is at Top Dead Center, the volume when you're actually burning). The compression ratio is calculated as the TOTAL (360cc+40cc=400cc) divided by the combustion chamber (40cc). This engine would have a 10:1 compression ratio.

However, the valves don't actually close when the piston is at absolute bottom, believe it or not, the air is still moving into the cylinder. The valve actually closes a little later, the piston has already started it's upward travel on the compression stroke. This is the Dynamic Compression. It's not when the piston is at the bottom, but the compression ratio when the valve actually closes.

Let's pretend, in our same 360cc engine, that the piston has started to move up and takes up 20cc of that space before the valve closes. Now we have 380cc (340cc plus the 40cc combustion chamber) divided by our 40cc combustion chamber volume.

380/40=9.5

This is a far cry from our static of 10:1.


As you can see, the static compression is based on the engine design alone. You can change it with pistons that take up more of the combustion chamber, but the dynamic compression actually changes based on the camshaft specifications, because different camshafts close the valves at different times.

Needmorehp
03-05-2011, 08:24 PM
XR400.............. .326, .321, 240, 244
HRC................. .350, .339, 254, 256
GT Thunder....... .350, .345, 256, 256
WB Track.......... .350, .345, 256, 256
WB All Around.... .345, .335, 240, 248
WEB 450/451..... .350, .345, 256, 256
WEB 479........... .378, .378, 250, 250
WEB 463/9i....... .385, .370, 272, 270
Hotcams stg 1... .354, .354, 246, 246------Intake centerline 106, Exhaust centerline 107
Hotcams stg 2... .354, .350, 254, 248.5----Intake centerline 106, Exhaust centerline 104.25
HC stg 2 (old).... .348, .349, 254, 254------Intake centerline 106, Exhaust centerline 107
Hotcams stroker. .358, .354, 262, 257------Intake centerline 110.5, Exhaust centerline 104.5
Megacycle x1..... .346, .346, 246, 246
Megacycle X2..... .378, .378, 254, 254
Megacycle X6..... .402, .385, 270, 262

I have a magnum cam and the #'s listed are the same as the gt thunder, wb track and web 450/451 not sure if there are any other specs to take into account hoping it was not a waste of money for a 416 mx build. I was wondering if a port job or should i go +1 valves and if 11-1 or 12-1 compression piston? Thanks

Mr-Sleeper-34
05-11-2011, 02:12 PM
How many guys are running the Part#1043-2 stage 2 HC on their (stock) 400ex's? I purchased one thinking it would be a good cam to have for my 4wheeler, but I have been reading that a stage 1 might be better suited. I have no desire to build the motor as I already have two other projects in the works.

I'm just looking for a bolt and go operation for some weekend fun(trail riding). Would you guys recommend I sale the stage 2 and get a stage 1, or keep the stage 2? I will be running a LEXX muffler on a stock header with the tube welds dremeled out for a little better air flow.

-mr34-

tri5ron
05-11-2011, 11:30 PM
I posed this question to Steve, and mentioned a possible addition of the +6 key with a stage 2 cam, on the stock bore. surprisingly to me, the responce/opinion was quite different than I would have figured it.

(I'll leave his exact responce out of it, in case HE would like to weigh in on it here).

I'd really like to hear from both GPracer2500, and Wheelie,
to see what their opinions on this would be comparatively...

How would a 400EX stock piston/bore with a stage 2 hot cam, and a +6, timing key perform,...

vs.

a 400EX stock piston/bore with a stage 1 hot cam, and stock, (OR,... +6) timing key ?

(Keep in mind, this question/comparison is for a STOCK Bore, STOCK Compression 400EX)

GPracer, and Wheelie,..... would you guys mind weighing in on this ???

Steve ??? Pipeless ??? Beags ??? Nacsmxer ??? ZRpilot??? wilkin250r???

Thanks

honda400ex2003
05-13-2011, 08:48 PM
i will post my individual experiences with the keys, though it seems to be a bit different than some others.

I feel that the keys help out top end with more advance.

so a 6 degree with a stage 2 would result in more top end than a stage 2 with a stock key with the same setups for comparison. the low end falls off as a result of this timing advance also.

i dont have any numbers or anything to back this up though, which is why i have issues with anything on the subject.

just my experiences, thoughts?
steve

trxPOWER
05-14-2011, 03:29 PM
speaking from experience, stage two cam on a stock motor makes it lazy and the power was not impressive at all.

DirtyBirdRacing
07-13-2011, 11:08 PM
I have Read trough this all and I cant make since of anything...

I have a 100% Stock 01400EX with a slip on, what Cam and Piston should I run If I wanted to up mid - high but not really loose bottom end? If that if even possible...

tri5ron
07-14-2011, 12:38 AM
Originally posted by DirtyBirdRacing
I have Read trough this all and I cant make since of anything...

I have a 100% Stock 01400EX with a slip on, what Cam and Piston should I run If I wanted to up mid - high but not really loose bottom end? If that if even possible... on a stock bore, stock compression piston,...
You'd probably be quite pleased with a HC stage 1.
the stock compression does not really support the flow of a stage 2,....
without sacrificing bottom end.

Add to that, a Uni air filter, outerwears lid, +6 timing key, and a '04-'05 450r carb. (PROPERLY RE-JETTED of course)
You will then be at 32 - 33 Whp,... (as compared to your 26-28 Whp now).

See my carb comparison thread, ( in the stickies ).

and before you even ask,.....
NO,.... you will NOT gain anything with a aftermarket CDI, or coil. They are a complete waste of money, ESPECIALLY on a stock piston configuration.

but before you do ANY of that,...
You will be far better served,...
With a pair of good front shocks.

DirtyBirdRacing
07-14-2011, 10:13 AM
Would it matter if I ran a K&N filter? sorry for got to mention that I was running that before

Thanks for the help.



Originally posted by tri5ron
on a stock bore, stock compression piston,...
You'd probably be quite pleased with a HC stage 1.
the stock compression does not really support the flow of a stage 2,....
without sacrificing bottom end.

Add to that, a Uni air filter, outerwears lid, +6 timing key, and a '04-'05 450r carb. (PROPERLY RE-JETTED of course)
You will then be at 32 - 33 Whp,... (as compared to your 26-28 Whp now).

See my carb comparison thread, ( in the stickies ).

and before you even ask,.....
NO,.... you will NOT gain anything with a aftermarket CDI, or coil. They are a complete waste of money, ESPECIALLY on a stock piston configuration.

but before you do ANY of that,...
You will be far better served,...
With a pair of good front shocks.

Mr-Sleeper-34
07-22-2011, 07:09 AM
I'm going to sell the stage 2 cam, pick up a stage 1 cam with a Curtis Key and honed stock header/LEXX muffler combo. I mainly do trail riding, so these mods should suite me well.

Mr-Sleeper-34
11-02-2012, 07:26 PM
(Full circle once again. Look who was the last to post in this thread #yawn.)

Hotcams stg 2... .354, .350, 254, 248.5----Intake centerline 106, Exhaust centerline 104.25

Megacycle X2..... .378, .378, 254, 254

^So I'm I reading that the Megacycle x2 is a better option than the Stage 2 HOTCAM going by the specs?