hotcams pro's/cons?

[hondaking52]

i got my head cover off...might be getting a hotcam cheap, anything else i should to while i'm in there?, and do the cams mess anything up?

thanks

[Pipeless416]

if you're doing a cam, you should also bump the compression ratio up higher than stock. as with anything that adds extra power, a cam will put a little more stress on things such as valve springs and rockers. you probably won't notice a difference in reliability though.

[hondaking52]

ok, and i dont really wana go high comp cause i got the timing key also..

[Pipeless416]

ditch the key. you will see a much larger gain with high comp and a cam.

[hypersnyper6947]

I would change the valves if i were you. I put a stage 2 in and i did not change my valves, b/c i didnt know i had to, and it dropped 2 valves and destroyed my whole motor. I would have rather spent a little cash on new valves and having the head serviced rather than having to buy a whole new motor. Although i love the motor i have now its more powerful than the 440 i had, it just would have been a lot cheaper the other way.

[hondaking52]

i dont really want to get into pistons and such.. and wat do i need to get as of valves? more clearence or wat? explain please..

[NacsMXer]

Originally posted by hondaking52
i dont really want to get into pistons and such.. and wat do i need to get as of valves? more clearence or wat? explain please..

You're really leaving a lot on the table by doing a cam and not the piston but if you must I would suggest to keep the cam mild (stage 1 Hotcam). Don't worry about doing the valves if you go this route.

[hondaking52]

Originally posted by NacsMXer
You're really leaving a lot on the table by doing a cam and not the piston but if you must I would suggest to keep the cam mild (stage 1 Hotcam). Don't worry about doing the valves if you go this route. thats wat i'm getting is a stage 1.

[hypersnyper6947]

call hot cams and see what they say about the whole valve thing

[rob_990]

Originally posted by hondaking52
i got my head cover off...might be getting a hotcam cheap, anything else i should to while i'm in there?, and do the cams mess anything up?

thanks

id put a crf450 timing chain in there and you can use the sparks key up to a 416.also if you wanna up the compression a little bit cause you will lose some with the cam put a xr400 headgasket in there its not hard to do since your already half way there. ive been running stock valves with a stage 2 and i havent had any problems with valves.

[ae13291]

i will be doing the same hotcam stage 1 with a timing key. its a real good mod and you dont need to mess with the compression or piston. it will be a great combo. make sure to use lots of assembly lube on the cam when u get it in

[hornetgod13]

I installed a Hotcams Stage 2 cam, Wiseco 11:1 High Compression Piston, HD Cam Chain, XR400 Head Gasket, Monster Coil and aftermarket Rev Box. I removed the advanced timing key as per Curtis Sparks recommendations. I've ran this set up now for well over a year and it's awesome! It's an entirely different quad. The timing key and stage 1 cam are just a drop in the bucket. It's not much harder to bore and hone and install a better piston.

Side note: I still have the stock valves installed. I did however, replace the valve seals while I had it apart.

[hondaking52]

i know uping the compression is going to make it better, but i dont really wana fork out tht much dough right now....just wanted to know if there where any drawbacks to the cam, and why is the crf450 cam chain better?

thanks

[scuzz]

I had the "stage two" on my stock-bored 400EX and never had any issues. I was quite pleased with how well it did with the filter and exhaust.

No reliability issues either. Of course I'm religious about maintenance.

I can't believe in every one of these threads no one mentions this until I do then they all say "oh yeah"

You have a good possibility of loosing low-end without going to a high-compression piston and a aftermarket cam.

You might...MIGHT not notice that big of a loss with a stage 1 since it's a mild cam, but it'll still be there.

Aftermarket cams increase the duration the intake and exhaust valves stay open, which in effect lowers your compression. That is typically why people do piston's at the same time. 450's can get away with it because they have fairly high compression stock, but 400ex's are low. The cam will make it lower.

If you want more pep and don't want to replace the piston, look into a stock xr400 cam and a stock xr400 head gasket. The cam is slightly more aggressive then the stock 400ex and the head gasket is a little thinner.

Then look into the 450r carb.

[NacsMXer]

Originally posted by hondaking52
i know uping the compression is going to make it better, but i dont really wana fork out tht much dough right now....just wanted to know if there where any drawbacks to the cam, and why is the crf450 cam chain better?

thanks

The CRF cam chain is wider, stronger, and less prone to being stretched like the stock 400EX chain.

[Pipeless416]

Originally posted by DMC-4OOEX
I can't believe in every one of these threads no one mentions this until I do then they all say "oh yeah"



Originally posted by Pipeless416
if you're doing a cam, you should also bump the compression ratio up higher than stock.

Originally posted by Pipeless416


oops, kinda breezed through the thread and didn't notice your post. Sorry.

But on a different note, you didn't really explain why, a lot of people dont know so don't think much of it. (not trying to be an a-hole so please don't take it that way)

[hondaking52]

....i have a timing key so my comp is already uped a bit...but thanks for the info, and i will look into the timing chain NacsMXer

Originally posted by hondaking52
....i have a timing key so my comp is already uped a bit...but thanks for the info, and i will look into the timing chain NacsMXer

Timing key doesn't raise the compression it just changes when the ignition fires. It turns the flywheel foward making it fire sooner then stock and giving it more time to burn.

(And please don't take that as an insult, seems everyone assumes im attacking them when I say things like this..)

[RaceinCircles]

How much is the crf450 cam chain? jw

[hondaking52]

Originally posted by DMC-4OOEX
Timing key doesn't raise the compression it just changes when the ignition fires. It turns the flywheel foward making it fire sooner then stock and giving it more time to burn.

(And please don't take that as an insult, seems everyone assumes im attacking them when I say things like this..) no no, its ok, always open to more info :)

[smorris1]

I am running a stage 2 with stock everything else besides pipe, filter and jetted. Its what came with the bike when I bought it but it runs perfectly.

[rob_990]

Originally posted by RaceinCircles
How much is the crf450 cam chain? jw

i think i paid 30-40 bucks for mine. but i know its like 20 bucks cheaper than stock and its way stronger.

[RaceinCircles]

Cool, Thanks Rob

[TP450R07]

If your going to run the 450r timing chain get the 06+ it is shorter the 04-05 is to long and will have to much play.

[Pipeless416]

Originally posted by TP450R07
If your going to run the 450r timing chain get the 06+ it is shorter the 04-05 is to long and will have to much play.

that is not true. mostly everybody that does this for some reason chooses the 2002 chain, including me. works perfectly.

edit: my brother just pointed this out.. we're talking about the crf450 timing chain, not the trx450r chain.

[brian76708]

Originally posted by Pipeless416
that is not true. mostly everybody that does this for some reason chooses the 2002 chain, including me. works perfectly.

yea i used the 02 chain two it worked great.

[rob_990]

mines an 03
im pretty sure any year will work

so its the exact same size length wise? Its not wide enouh to be rubbing anything?

[brian76708]

Originally posted by FlewByU352
so its the exact same size length wise? Its not wide enouh to be rubbing anything?

yea it just barley fits on the sliders.

[ae13291]

Originally posted by DMC-4OOEX
Timing key doesn't raise the compression it just changes when the ignition fires. It turns the flywheel foward making it fire sooner then stock and giving it more time to burn.

(And please don't take that as an insult, seems everyone assumes im attacking them when I say things like this..)

it actually turns the flywheel more back so the ignition fires later forcing the piston down even harder.

[TP450R07]

My bad should of read crf but if you get the trx chain get the 06+ the 04-05 is one link to long

[tri5ron]

Originally posted by ae13291
it actually turns the flywheel more back so the ignition fires later forcing the piston down even harder.

^^^^^incorrect.^^^^^

Advancing the timing means it fires sooner.
Retarding the timing would mean it fires later.

By firing the spark 6 degrees earlier,
it provides for more "burn time", and more complete fuel burn overall.
Allowing for more power to be generated per each combustion cycle.

The Lower the compression any given engine has,...
the more the timing can be advanced without causing detonation, (Pinging)

The Higher the compression any given engine has,..
The less the timing can be advanced until causing detonation.

Hence, this is why it is not recommended to use the Timing advance key, (in a 400ex), with a piston that has a compression ratio of 12.5 : 1 ,or higher.

using a piston with 10.5, or 11 : 1 compression will still tolerate use of the timing advance key. (In a 400EX).

Now with all that being said,...
The higher the compression,...
or the more the timing is advanced,...

the more likelyhood that you will need to run priemum grade, (91 or 92 octane) fuel.

low compression = lower octane requirements
higher compression = higher octane requirements

[ae13291]

Originally posted by tri5ron
^^^^^incorrect.^^^^^

Advancing the timing means it fires sooner.
Retarding the timing would mean it fires later.

By firing the spark 6 degrees earlier,
it provides for more "burn time", and more complete fuel burn overall.
Allowing for more power to be generated per each combustion cycle.

The Lower the compression any given engine has,...
the more the timing can be advanced without causing detonation, (Pinging)

The Higher the compression any given engine has,..
The less the timing can be advanced until causing detonation.

Hence, this is why it is not recommended to use the Timing advance key, (in a 400ex), with a piston that has a compression ratio of 12.5 : 1 ,or higher.

when u install the timing key you move the flywheel counter clockwise. if the engine turns clockwise that means you are making the motor fire a lil later.

[tri5ron]

Originally posted by ae13291
when u install the timing key you move the flywheel counter clockwise.

^^^^correct^^^^


if the engine turns clockwise that means you are making the motor fire a lil later.

^^^^The engine turns counter-clockwise, when viewed from the flywheel side^^^^


on edit, I didn't do the qoute thing correctly. I tried to split it in two, to reply to the two seperate statements. hope I didn't confuse anyone with that....