Will bigger cams effect reliability of Honda 400ex

[DeathMoose5000]

does bigger cams effect the relableity of his 400ex and will it keep up wit 450

[Stoopidbot1]

No it won't hurt reliabilty. Depending on what stage you get. Most increase mid-high end or the RPMs. You won't gain top speed without changing your gearing. Maybe 1-2 mph.

[DirtDemon]

I think it would take more than cams to make a 400ex keep up with any 450. But, it is a good start and like Bot said, it won't hurt reliability much, as long as you don't go with a cam with a really aggressive profile. If you aren't doing a bunch of other mods to go with it, you don't really want really aggressive cams anyway.

BTW, I changed the thread title.

Edited November 12, 2009 by DirtDemon

[CK1999_400ex]

a stage 1 or stage 2 cam will not hurt ... but if you go with any thing larger then it will ! i run an XR 400 cam in 1 of mine and it was a big difference .. the dirt bike cam is a little more than a stage 1 cam for the 400ex .. but is a little less than a stage 2 ... its kind of in the middle ... and it is a stock honda cam and is legal to run in any stock 400 class ... i run a few hill climbs that the motor must remain stock... so its legal but its kind of not ...lol... if ya want to know any more about the 400ex send me a message ... i own 2 of the 400 ex's and have 9 motors that i use for different races and or classes that i run...

[rrdh]

im looking into getting a cam. but everyone is talking about it giving u more high end. i want more low end aswell... what do i do for that?

[CK1999_400ex]

use a stock XR 400 dirt bike cam ... they will give you alot more grunt through the whole rpm range .. and they are fairly cheap on ebay

[Stoopidbot1]

im looking into getting a cam. but everyone is talking about it giving u more high end. i want more low end aswell... what do i do for that?

Go up a tooth in the front.

[DirtDemon]

Go up a tooth in the front.

I think you meant to say go down a tooth in front, or up in the rear.

[Stoopidbot1]

Thanks, I ALWAYS mix it up.

[rrdh]

alright thanks.. will try that

[DirtDemon]

Keep in mind, when you start changing the gearing, you will sacrifice top end speed for low end performance and vice versa. Changing the front sprocket will make more significant differences, maybe more than you are looking for. Changing the rear sprocket will make a more subtle change, adding or removing teeth on the rear sprocket has the opposite effect of changes made to the front sprocket. If you don't want to loose top speed, then look to motor mods to get the low-end boost you are looking for. It sounds like the XR cam will do well for you, CK1999 seems to know that machine inside and out. If you don't mind losing a couple mph, then a sprocket change is an easy, low cost way to get the low end perfomance you want.

Edited November 21, 2009 by DirtDemon

[aces86]

will any year of xr 400 cam work? I have a 07 trx400ex, looking to make it come alive.

[DirtDemon]

I checked a Honda parts fiche and it looks like the camshaft part# was the same in all years. So I would just get the newest one you can find if you buy a used one. If you buy a new one, the year won't matter because they are all the same.

[CK1999_400ex]

i also have the 07 motor and my cam is an 98 xr400 ... if you really want your 400 to come alive buy a complete xr400 motor and put the internals from it in your ex block and use the xr side cases and have kick start ... it will rev alot faster and be nasty ... but it dosent have the rotating weight of the ex motor and will stall alot easyer ... but it will keep up with any stock 450R hondas and is leagal in most all compitions for the 400 class ...

[opiewhitaker]

does bigger cams effect the relableity of his 400ex and will it keep up wit 450

no they dont if you match them with ur motor if you run stock highcompression pistion go with a stage 2 hot cam but you must remove the compression release. i have a 400/ex 460 big bore mil crank stroker with a stage 3 but i can go to webb stage 5 using 114 octane this big can be seen o this web site.

[greasemonkey259]

JESUS CHRIST! Is a stage 5 Cam really that important?

[Stoopidbot1]

Don't let certain people fool you. Web Cams does not make a "stage 5". Their different cams are not called stage anything. They have grind numbers. They have 3 different styles of cams for the 400EX.

[greasemonkey259]

That's what I thought. I have a stage 2 in my 05 400, I knew there was 3 differant ones. If i went up to the craziest one I would have to do a bore on it. I really don't wanna do that to my motor.

[Stoopidbot1]

Web's "stage 2" requires new rockers and stuff the "stage 3" requires new just about everything.

[greasemonkey259]

I put in a stage 2 hot cam in. The guys at the local ATV shop said I wont need.

[Stoopidbot1]

Web Cams are more aggressive that Hot Cams. I run a Stage 2 Hot Cam in my 450

[greasemonkey259]

Really? I want more of a lop in my cam really. If I put a Stage 2 Web Cam will it give it more of that?

[Stoopidbot1]

Really? I want more of a lop in my cam really. If I put a Stage 2 Web Cam will it give it more of that?

You need additional parts to run their level 2...

Performance profile designed to increase overall performance. Requires Performance Valve Spring Kit, Shortened Valve Guides, High Compression Piston, Exhaust System, and Hardwelded Rockers.

[greasemonkey259]

Damn, so it runs like a whole new machince I'm guessing.

[Stoopidbot1]

Oh yeah, Hot Cams is the camshaft company for the average/rec rider. The cam the everyday guy buys. Web cams is what people who build their motors run. That is what Dasa puts in their motors. That is what the pros like Joe Byrd and all the use. My racing buddy who has a 62 RWHP on a TRX450 built by Dasa uses the level 2 from Web. I run a Hot Cams and love it.

[greasemonkey259]

Yea I love my hot cam but doing that much motor work to mine is gonna cost a pretty pennie for just the parts. So I will just hold off on that for a bit. at least till I get college out of the way.