416ex cam vs compression

[matts27]

I'm trying to figure out if leaving the stock cam on a 416ex with 10:1 vs 11:1 with a Stage 1 cam. I like the idea of getting rid of the stock cam since it's been in use my quad it's whole life ('02) and upgrading it with the new fresh bore & piston with a nice clean valve train. My main concern is overbreathing the motor and also creating too much heat with the higher compression and larger cam profile. Also, I would like to keep running 93 octane and all I'm in is trails and rarely do I hit 5th gear ( only when a trail is closed and we rip down the road ).

The cylinder was pretty good but the rings were shot pretty bad and I'm the 3rd owner and have cleaned up almost all the issues I've had over the 2 years I've owned it. Haven't gotten around to Mic'n the cam yet but it was pretty clean with no heavy wear or irregular pitting and such when I tore the motor down so I feel the cam will probably check out. I just hate the cam decompressor tick and feel that it's probably pretty beat so was thinking of the swap. Just looking for some input either way, appreciate any first hand advice. Thanks, Matt

[trailrider894]

I am kind of confused what exactly you are looking for, but from what i understand...

A 416ex with 11:1 with Stage 1. DO NOT DO A STAGE 1. Do a stage two. The stage 1 is not designed for bored over engines. You can run 93 with an 11:1 piston with no problems. Heat wont be a huge problem. Also, what is your definition of overbreathing the motor? i've never heard that term before...

[jjm400ex]

i agree stg2 cam and 11.1 comp piston.

[matts27]

"Overbreathing"

I'm refering to the cam being too large for the stock components. I'm still going to run my stock carb, air-box w/lid, snorkel, exhaust and valving.

I didn't realize the stg 1 is designed for a stock motor.

[trailrider894]

Originally posted by matts27
"Overbreathing"

I'm refering to the cam being too large for the stock components. I'm still going to run my stock carb, air-box w/lid, snorkel, exhaust and valving.

I didn't realize the stg 1 is designed for a stock motor.

It won't over breath... YOu'll just have to re-jet your carb. But you'll see minimal gains without an aftermarket intake and exhaust.

[matts27]

Thanks for the replies. Appreciate it, I mainly trail ride so 2nd to 3rd gear a lot, gotta keep the pipe legal for the forests and the water/mud makes the snorkel almost needed a bunch of times. Was thinking the stock components would kill any extra volume. Matt

[trailrider894]

Originally posted by matts27
Thanks for the replies. Appreciate it, I mainly trail ride so 2nd to 3rd gear a lot, gotta keep the pipe legal for the forests and the water/mud makes the snorkel almost needed a bunch of times. Was thinking the stock components would kill any extra volume. Matt

I would look into the Lexx pipe.

[sneaky11]

I'll go 10:1 with the stg 1 cam on a 87mm bore. That way you'll get a good dynamic compression, without any overheating issues.
This mix will give you a lot of bottom end torq.

If you go 11:1, like others said, i'll go stg 2 for sure.

both setup should be good with 93.

Stock cam on a 416 High C/R is not a good idea.

As for the pipe, I don't think you need a full pipe, just grind the weld in the stock head pipe. I'll put the FMF Q4 for low noise and a little bit more bite.

You definitly should look at the 450r carb! Cheap, and maybe the greatest mod on the EX.

maybe you already go over this reading: How to pick a cam (http://www.exriders.com/vbb/showthread.php?s=&threadid=392231)

[wilkin250r]

I don't really agree with the stage 2 cam. The stage 2 has a much longer duration, which will build power in the upper RPMs, but he alread says he's in pretty tight trails, it doesn't sound like he's in the upper RPMS very much. And the stage 1 cam actually has slightly higher lift on the exhaust, giving him a little better breathing without sacrificing low-end grunt.

It sounds like he needs his low end, I'd totally reccomend the stage 1 over the stage 2 cam.

[sneaky11]

Originally posted by wilkin250r
I don't really agree with the stage 2 cam. The stage 2 has a much longer duration, which will build power in the upper RPMs, but he alread says he's in pretty tight trails, it doesn't sound like he's in the upper RPMS very much. And the stage 1 cam actually has slightly higher lift on the exhaust, giving him a little better breathing without sacrificing low-end grunt.

It sounds like he needs his low end, I'd totally reccomend the stage 1 over the stage 2 cam.

x2
that's why I said 10:1 stg 1 should be the best for tight low speed trails.

[trailrider894]

Originally posted by sneaky11
x2
that's why I said 10:1 stg 1 should be the best for tight low speed trails.

exactly... but 11:1 needs a stage 2.

[matts27]

Thought the stage 2 would need the 11:1, seemed like a must. I've read all the posts on cam choices and gone over the grinds repeatedly, this is why I figured I'd throw out the post. Everyone seems to run different set-ups with happy results for each application. My concern was with the stock cam & the decompressor. I understand all the principles behind the set-up by Honda but just don't agree with the benefit. More moving parts drain more power. Lighter can be better, but the aftermarket grinds seemed a little too agressive for any power gain unless I go 11:1. But, everywhere I read about the stg 1 cam it sounds like it falls on it's face in the upper rpm's. The stock seems to pull well but I'd like to dump the decompressor and "freshen" the cam up too!

I appreciate the replies.

[wilkin250r]

Originally posted by matts27
But, everywhere I read about the stg 1 cam it sounds like it falls on it's face in the upper rpm's.

I'll admit I haven't tested each and every cam, but I think this is mostly perception.

Most people couple the cams with a high compression piston, and higher compression WILL kill the upper RPMs. And if the engine has more power everywhere, except the same power at the highest revs, it will FEEL like if falls off worse, when in reality it falls off exactly the same.

[CJM]

Lets do a comparison:

1. Stock 400ex, hotcam stage 1
2. 416 11:1, hotcam stage 2, open airbox lid, exhaust.

The above is my friends and mine (#2 is mine). He likes his lowend power, he has no real topend with the cam. yes its there-but it just kinda tapers off to nothing it seems. But even if the compression was higher I dont think a stage 1 would work to well since it was designed for a stock engine (stock bore and basically nothing more than an exhaust), it was designed for trail riders in mind tho and does have good lowend till you hit 4th gear where your topend mostly is.

Now mine of course is obviously gonna be faster, but I have plenty of torque-can lift the front up with ease in almost any gear. Would a simple piston and cam do all that without the rest of the mods-Im not sure.

What I can say is I have no issues flying thru some very tight trails with my setup. Not only am I quite happy with the entire thing, but everyone who has ridden with me is impressed. I have no issues at all keeping up with and pulling (depending on rider and setup) alot of 450s b/c I have a ton of torque. I can let off the gas 100% and be rolling and blip it and it pops up.

When I built it I only used high quality components. I have a wiseco piston, cometic gaskets (which are similar in thickness to the thinner XR400 head gasket). So maybe im getting more compression than you would using normal gaskets. I also run 93 octane without a single issue at all.

If you perhaps want to run a lesser compression than perhaps the sparks cam is the one to go with. Its been explained to me that its a 1.5 stage hotcam really the way the duration and lift is-maybe best of both worlds.

Still, what people often fail to understand about these engines is bore size is relative-its compression you want-thats where you make the power. If I could run a 12:1 piston on pump gas Id do it-we cant b/c the heads air cooled and generates to much heat with such a setup. This is why I recommend to everyone 11;1 and run on 93 with the supporting mods.