11:1 pistion and web cam?

[backwoods 400ex]

Hi i have a 2006 400ex with a lexx pipe,uni air filter,dyno jet 160 and 38, and an open air box. I wanna do a 11:1 wiesco std. bore pistion and a custom web cam from Rossier Enginering i was just wondering will i have trouble running 91 pump gas??? and will i notice a big power gain to justify the cost??? i ice race and i need some more power to keep up with the 450s and i DONT wanna sacrifce reliabilaty cause in like 2 years im building a 450 but still want the 400 for trail riding sorry this is so long but THANK YOU

[CJM]

Would be fine, Id use 93 to be safe just cause its only a few cents more tho.

[slightlybent47]

The answer is yes you’ll be fine on 91, but let’s all step back and look at this 89-91-93-race fuel issue. Your ex get at least 45- 50 miles a gallon. How much riding are you doing? Is a few cense a gallon going to be that big of a deal? Because if $0.10 a gallon is going to break the bank, you have bigger problems to worry about. Quit being such a tight wad and spend a few pennies and get what you need.
If you skimp on the fuel then what’s next? Skimping on the oil and how often you change it? Treat your bike and your riding gear like it was worth a million dollars and don’t skimp on anything.

[backwoods 400ex]

they gas staition im my town only sells 91 thats why i wanna run 91 if they had 93 id get 93 and on the trails if i need gas i wanna beta use what they got and not have to carry gas i just wanted know what i could run in this motor safely

[honda400ex2003]

I plan to run 91 in mine most of the summer, i guess ill see how it goes when the time comes and cross the bridge at that time. I cant get 93 without driving the 15 miles to town, I can get 91 about 2 miles away with non-ethanol. If i have to get 93 i will, maybe ill mix some 110 in there with 91 if needed. Ill see how it goes this spring.

steve

[backwoods 400ex]

Okay thanks..will i notice a big power increse?? the guy at Rossier said i will just wondering what you guys thought??

[honda400ex2003]

where are you from? I think it will be a pretty good increase for sure. Ill be doing my 440 this spring sometime and will probably have it dynoed again down at Rossier.

My 416 made 34 hp on their dyno with about 2years of riding on it.

Im hoping to get closer to 38 with some more stuff done to it this spring.

Steve

[honda400ex2003]

now if only i could talk dallas into hooking me up with his roller frame i would be set. Id use his stuff for the 440. Id turn mine back into 397cc and go completely stock with it. lol steve

[trailrider894]

I run 93 on my stock motor. :devil:

[slightlybent47]

Your not going to see any real power increase so don’t get your hops up on that.
Everyone has this idea that the higher the octane is the more flammable or the more power you will get. Octane rating only has to do with the flash point of the fuel. The lower the octane the faster it will ignite so in a low compression motor the low octane will light easer then the high octane will. When you get into a high compression motor the fuel needs to be more stable and have a higher flash point so that it dose not pre detonate before it’s supposed to. That’s where the pinging noise comes from; your fuel is firing before it’s supposed to and causing you to lose power.

Take jet fuel for example, everyone thinks that it so explosive but in fact jet fuel is nothing more then high grade kerosene and it actually has a low flash point. In other words it takes more heat to ignite it. But pre heat that kerosene and it will burn much hotter then gas will.

Everything that burns has a flash point, witch means at some point with just heat alone and no spark, will cause it to spontaneously combust. So a low octane fuel will ignite at a lower temp then a high octane will.

High octane fuel in a low compression motor may not explode with the velocity because the spark may not be strong enough to light it properly. And so you don’t get a good complete burn of your fuel. So it’s a waste of money to run high octane in a motor that doesn’t need it.

And if you run a low octane in a high compression motor it will light to fast or early just form the heat and compression alone before the spark plug actually fires. That’s pre detonation.

I hope that make since and helps clear it up for you.

[backwoods 400ex]

im from central wisconsin and race in the Central Wisconsin Ice Racing Asociation..i need the extra power to be able to compete with the 450s and do you know how much Rossier charges for the dyno? cause i had mine dynoed at power pac and got 26hp and when i get the pistion and cam i wanna see what itll be at THANKS

[slightlybent47]

Here is the reality;
A stock ex is 27-28 hp, and a stock 450 is 47 hp.
A built ex is around 50 hp and a built 450 runs around 65 hp.
Do you really think a ex will run with a 450 on a flat track where power is the key to wining a race?
Application is everything when deciding on what machine to ride. For flat track I would think the 450 would always have an advantage on the ex. But I could be wrong.

[trailrider894]

Originally posted by slightlybent47
Here is the reality;
A stock ex is 27-28 hp, and a stock 450 is 47 hp.
A built ex is around 50 hp and a built 450 runs around 65 hp.
Do you really think a ex will run with a 450 on a flat track where power is the key to wining a race?
Application is everything when deciding on what machine to ride. For flat track I would think the 450 would always have an advantage on the ex. But I could be wrong.

Hey, you make a good point... Lets help the guy though, not discourage him. I am sure he knows the reality of it anyway. The problem is that, i race MX and ride an EX. I know i can't lick the 450's like i want, but whatever i can't afford one so i am modding my bike to be better on the track. So lets help this guy get the info about modding his EX to help him win.

[honda400ex2003]

Originally posted by backwoods 400ex
im from central wisconsin and race in the Central Wisconsin Ice Racing Asociation..i need the extra power to be able to compete with the 450s and do you know how much Rossier charges for the dyno? cause i had mine dynoed at power pac and got 26hp and when i get the pistion and cam i wanna see what itll be at THANKS

im thinking that you guys should check out some of the dyno runs on rossiers site. you guys are giving way too much credit to these 450 engines when stock.

Last i knew, rossier was 50 for setup and 100 an hour after that I think. You have to either have a wider axle or spacers since you cant run stock width on their dyno.

rossier's number is 815-341-9919

steve

[Scro]

Originally posted by slightlybent47
Here is the reality;
A stock ex is 27-28 hp, and a stock 450 is 47 hp.
A built ex is around 50 hp and a built 450 runs around 65 hp.
Do you really think a ex will run with a 450 on a flat track where power is the key to wining a race?
Application is everything when deciding on what machine to ride. For flat track I would think the 450 would always have an advantage on the ex. But I could be wrong.

Not that it really matters, but a stock Honda 450 is 36-38 hp.

[honda400ex2003]

thank you scro for that info. I did not have time inbetween my classes to finish up the rest of that info i was providing. 36-38 is all that they are getting out of stockers according to all of the dyno charts i have been seeing.

steve

[slightlybent47]

Man I thought 93 was available everywhere. I have traveled quite a bit and I can’t recall not seeing 93 where ever I go. Regardless the guy is talking about running with 450’s and all he wants to do is bump the compression up to 11:1 and he only has 91 octane available to him. With the few mods he won’t be able to run as well as the 450 for ice racing. I would suspect that hp would be a big factor in how well you run on ice. The ex is a great machine but it has it limits and applications where it can do better then the 450. I’m not sure ice racing is one where the ex could do as well.

I would like to encourage him to do better but the ex is going to limit his performance.
Everyone is saying how much cheaper the ex is over the 450 but it’s really not that much deference. When you look at parts for ether machine the cost is very close to the same.
You can buy a used 450 with full suspension pretty cheap these days, compare that to building an ex and you are about the same.

I understand he may be trying to do the best whit what he has and nothing wrong with that. But I don’t want to fill him with false promises that his ex is or will be all that competitive to the 450. At least for the mods he wants and the racing he is doing. Yes he can do mods and get better performance but its going to be limited and he shouldn’t expect too much.
The ex will hang till the speeds get up around the top end 4-5 gear and the 450 will walk off and leave him on the top end.
If he still wants to do the mods he can, he should just know the truth so he can make the best decision and not to expect a miracle from the ex.

After all the 450’s are out running him, so that should tell you something.

[CJM]

To compete with a 450R, even a modified one you need the proper setup.

I found it, but it only works if the 450R hasnt had much more done to it than a cam and slip on and stuff-if its bored over forget about it your done.

The key is the rider, no you wont be flying past them but keeping up is key. Without keeping up you dont even stand a chance.

Still when your already starting off with a lowered powered machine and racing alongside machines that have about 10hp more it is tough.

[hondanator]

my 400 is 11:1 with a web cam and lexx exhaust. i love it, its great for the riding i do and has all the power i need. anybody have an idea what the hp would be?thanks

[slightlybent47]

I can only go buy what I’m seeing and what I have experienced.
When I first started racing I was on a stock ex and all the guys I race road 450’s.
At the beginning I could easily out run them all and the reason for that was my riding skills were better then those I was competing against. After about a year I was have trouble staying in front and was getting beat some of the time. Which meant that they were getting better and so was I but my machine was holding me back. I did not have the power to come out of corners and clear jumps that my friends were doing on there 450’s.
So I rebuilt the ex and added better suspension and more power. Then I was able to get the power I needed to clear those same jumps I could not do before and I could keep up and still beat the 450’s a lot of the time.
But as my friends continued to get better and faster on there 450’s my ex is not keeping up any more. And it’s not me it’s the bike holding me back. I have to ride harder and carry more speed and use momentum to try and keep up, the 450’s are clearing jumps that I just can't get enough speed to clear, so I have to roll those jumps. And the 450’s just walk off in the straits and there is nothing I can do to catch them.

We have a woods track that we ride and I can still beat them on that track because it’s so technical that the ex can do better then the 450.
But on tracks where speed and power are factors the ex just falls flat.
The ex is a great machine but there is a reason all the A class riders ride a 450.

CJM your one of the few that can see that the ex has limits and you can only do so much with it. Rider skill being equal of course.

[CJM]

Exactly bent, you just cant match a 450 with a 400 in the end, your starting off with another 50cc of displacement vs only 397cc of the EX. Even boring the EX and making more power you will still b e hurt by a relatively modified 450. There is no real replacement for displacement in this case no matter what you do.

Can my EX keep up with the 450's? Sure it can-but and the big but here is kicker: not everyone has the same skills, nor riding ability. So while I can keep up and if not best some of the guys I cant keep up with everyone as there are others who are more skilled than I am. I know in a drag I can jump off the line well, they gain a few lengths and then I catch up and either beat or tie them. But like I said, could be the rider or could be quad..or both.

Bottom line is if you want to keep up with the 450s you eventually either settle for a modified EX and beat them using skill or you switch to a 450 machine. Dont get me wrong, there is nothing wrong with starting on the EX and racing it-just have to know its limits.

FWIW: A 440 is nice-but I feel a 416 or 426 has a better power delivery b/c it revs much faster and generates less heat. What really works is a stroker-but then you get into alot of $$$ and unless you want to be unique you might as well buy that 450.

For trail riding the EX shines, but for the track it can keep up decently but it wont win against the 450 all that easy.

[backwoods 400ex]

Thanks guys i understand my little 400 wont beta walk 450s but in the class i run which is a beginers class we have to use knobby tires which belive me dont grab to well but i can keep up last weekend i bet a yfz its mostly about the rider in this class but i know to move up to more of a pro level class i need a 450 but i dont have very deep pockets im a senior in high school and got collage to think about too i just wanna beta be competative on a budget

[slightlybent47]

Yeah the ex is a great starter bike and can run strong against a bigger bike. And if that’s what you have to ride then so be it. Hey I still ride the ex and do well on it. There’s nothing wrong with fixing up an ex and racing it. Just as long as you know what you have and what its limits are. And if that’s what you want then go for it. You can always move up later as you get better and can afford it.
I bought my ex not to race but too trail ride with it. It just so happened I started racing it and didn’t want and couldn’t afford to buy a 450. At this point a 450 is where I need to go, if I want to progress and do better. Some riders find that the ex is all they need and don’t need to move up.
I’m just trying to give you all the facts so you can decide if it’s worth it to you.

[backwoods 400ex]

I know its hard to beat a 450 with a 400 but will the cam and pistion make it posible to do ice racing?