500cc kit 4 a 400ex???????? any info let me know

[redracing88]

i have a 400ex that i would like to get a 500cc kit 4. i heard of them but cant see to find them. i know the stroker crank makes it 460 so if i got a 440 sleave and a stroker crank what would that make it?? well let me know what you guys got for me plzzzz.

www.chad502ex.com has all the info u need

[ST87]

four stroke tech makes one or used too and TC makes a 505ex still i think not sure dont hold it against me.

[honda92]

Originally posted by blue450yo
www.chad502ex.com has all the info u need


44hp for a 490 kit? that seems really low.

[ride_red666]

no a 460 is a 440 bore with a stroker crank

[Chris S.]

Stroker motors aren't known for a big horsepower gain but when you look at the torque gains you start to see the benefit. When you switch to a stroker kit, changing your sprokets to maxamize the torque transfer to the ground to make more acceleration is neccessary. Stroker motors aren't going to rev as quickly generally. Correct me if I am wrong. If you compare raptor700 to a YFZ450 you will see two quads that make similar acceleration performance two different ways. Which is better? Depends on riding terrain.

[wilkin250r]

High revs are a must in order to build big horsepower. But the 500cc strokers just don't seem to rev as high. Big torque gain, but not a huge horsepower gain because of the limited revs.

[chad502ex]

admitting low hp graph on the 502 posted. My peak 502 hp dyno'd was 47. But as wilkins said a strokers purpose is not for hp it is for torque. Remember, hp is only a calculation of how the engine makes torque in the higher rpms.

HP = TQ * RPM/5250

If two engines produce the same exact hp, the engine that makes the power faster wins.

I went through the digital archive to pull a graph with hp over rpm to calculate torque, but I never printed any out while on the dyno. My calculations for the 44 dyno printout are at about 45 lbs or torque at 4500 rpm

However, since then I've done porting and looking at my port on the 502 that was done by my machinist years back, I bet I could easily re-port and get low 50's hp and high 40's tq if I was interested in higher hp numbers. I do plan on re-porting though and dyno'ing on Mobile Dynos setup probally within a month or so.

hope this helps.

[chad502ex]

Originally posted by blue450yo
www.chad502ex.com has all the info u need

heh! thanks for the website plug. I havn't had much time to update lately with all the building done on the two 530R's the 550 and my latest 450R project.

As soon as the 450R is done the 502 will be re-ported and dyno'd again. :D

After that, the website before spring riding. :D

[2muchquad]

man if you open up those ports a lil'bit more,im sure there are some more rpms hidin in there:D i like your site

[chad502ex]

Originally posted by 2muchquad
man if you open up those ports a lil'bit more,im sure there are some more rpms hidin in there:D i like your site

yes, i agree 2. It's apparent that the porting on the 502 is not setup for hp, but looking at the pic above of the 502 ports makes me feel a bit constricted with my breathing,.. lol


thanks for the website comments. i guess i should spend more time with updated info to help out more ppl.

[TWISTED]

What do you know about horsepower anyway????? What's up???? How's the new motor coming?

[XCRACER26]

FST has a 500 kit. thats what chad duvall used to run.

the 500 kit is susposed to be safer than a normal 440 kit. cuz of the sleav or sumthing. not for sure

[chad502ex]

Originally posted by TWISTED
What do you know about horsepower anyway????? What's up???? How's the new motor coming?

didn't you read a hint about the new 450R build in the dyno section?

I have all the new HONDA OEM parts (i.e. bearings, seals, gaskets)

custom harmonically balanced,
polished,
lightened,
blueprinted,
welded
chamfered oil passages,
cryo-coated,
knife rod.

14:1

my custom "DRG" porting

45mm-to-43mm taper bored FCR

customer linearly accelerated intake

custom ignition

should be done in a couple weeks.

pictures forthcoming :macho

out of all the builds i've done, this one xcites me most... :D

[TWISTED]

BE AFRAID, BE VERY AFRAID!!!!! Can't wait!!!!

[chad502ex]

Originally posted by TWISTED
BE AFRAID, BE VERY AFRAID!!!!! Can't wait!!!!

and of coarse your GOING to ride it HEHE!

[TWISTED]

DEED I AM!!!!

[Chris S.]

Chad - I just put in a 500fst motor that I bought from 44oex on this forum and wanted to ask you what carb you are using. I'm going to use my 450r carb. Also, are using the stock cdi box and stock rev limiter settings? What sproket combos would you use for dune riding?

[chad502ex]

Originally posted by Chris S.
Chad - I just put in a 500fst motor that I bought from 44oex on this forum and wanted to ask you what carb you are using. I'm going to use my 450r carb. Also, are using the stock cdi box and stock rev limiter settings? What sproket combos would you use for dune riding?

Chris,

WTG on your new 500. Is yours the 496cc or 502cc? what bore?

right now i'm running a 450r stock carb. seem to flow more than my Lectron powerjet carb. the difference i think is the 502 likes the bigger diameter 42mm carb, compared to the 40mm Lectron.

Because of the 502 increased power and tq, I had to up one tooth on the front sprocket from stock with 22" tires on the back. I ride the 502 mostly xc, but for you riding dune I would start with one up on the front with 20" sneakers on the back.

the cdi is +1000 rpm

[Chris S.]

Chad - I believe that I have a 490cc. I am having trouble getting it to start, I have tried a 45, 50, and 52 idle jets and 165, 168, and 170 main jet. What combnation of jetting do you use and what combo would you recommend? I have a full HMF exhaust and open airbox with UNI filter and like already mentioned the 450r carb. The head had a mild port and polish job with a web cam. I will be getting a 16 tooth front sprocket for it and I already have 20" paddles.

[chad502ex]

Originally posted by Chris S.
Chad - I believe that I have a 490cc. I am having trouble getting it to start, I have tried a 45, 50, and 52 idle jets and 165, 168, and 170 main jet. What combnation of jetting do you use and what combo would you recommend? I have a full HMF exhaust and open airbox with UNI filter and like already mentioned the 450r carb. The head had a mild port and polish job with a web cam. I will be getting a 16 tooth front sprocket for it and I already have 20" paddles.

i think your still a bit rich on pilot. I think I run a 38 slow in the stock 450r carb, but honestly 40 may be closer (i'd have to check the main tommorrow for ya)

It's real tough to guess your jetting with the porting you have on your 490 without seeing it. In other words, port size, cam timing, and displacement all effect the signaling on your carb. my point is I would go lower until it starts good, but make sure you don't get kick back through the electric starter sprag. if the pilot is too lean kickback occurs and you'll be replacing spags often. The bigger the port the lower the velocity, the lower the signaling off idle, the bigger the jet required.

__________________
smaller ports = faster velocity = more bottom end = lower or same top end
_________________
big ports = slower velocity = lower or same bottom end = more top end
_________________
big port with velocity stack on lid = more bottom end velocity with stack = same or slightly better top end
_________________
or,.... another type,..... additional information forthcoming :D

[Chris S.]

Chad - You were right, I switched to a 38 pilot and it fired right up. I have a 160 as the main jet. After I cold start, I have to wait for that engine to warm up or it will just stall if I give it any throttle. Once warm it revs strong and faster than I excepected. Now I need to get new sprockets and I think I will get a new CDI. Do you know if the one from FST for about $100 is any good? Thanks Chris

[chad502ex]

Originally posted by Chris S.
Chad - You were right, I switched to a 38 pilot and it fired right up. I have a 160 as the main jet. After I cold start, I have to wait for that engine to warm up or it will just stall if I give it any throttle. Once warm it revs strong and faster than I excepected. Now I need to get new sprockets and I think I will get a new CDI. Do you know if the one from FST for about $100 is any good? Thanks Chris

glad i was able to help you.

I will never buy from FST, too much bad history for me there.

However, I would have to say that fst cdi would be the same as white brother ignition. So, either-or would work

let me know if you have any other questions i may be able to help with.

good luck.