400 to 440 conversion

[redlined94]

I am thinking about getting a 440 kit with the new sleeve and the different cam and the works and I was wondering if anyone has this set up and what they have noticed in power difference from the stock size to the 440? Just let me know what you guys think about it. Thanks!!

[Knips178]

it made a huge improvement. But only if you run a good pipe and air filter.

Night and day!

[sportraxkid]

Originally posted by Knips178
it made a huge improvement. But only if you run a good pipe and air filter.

Night and day!

I agree totally different bike!

[400exrider707]

Personally I would stay away unless you plan on doing the "works" to your bike to compensate for the 440. Like hardfacing your rocker, heavy duty cam chain, oversize head studs, and probably an 8 plate clutch setup. JMO

[Knips178]

you don't need all that stuff. you only need hard faced rockers if the cam you get says it needs them. Hotcams stage 1 or 2 don't use the stock rockers just fine. A heavy duty cam chain is optional, but not necessary. If your stock chain is questionable, just replace it with another stocker, it'll be fine. You don't need a special clutch setup, just use heavy duty springs and a good set of pads/plates. The head studs are also optional. I ran standard studs and didn't have any problems.

Now, having said that. Any of those additions would help your piece of mind knowing your likely hood for a failure is slightly diminished. But, none of them are needed to do this conversion.

I know this because I went through this exact same process.

[ZSK]

Do all of the heavy duty parts now and save headaches later. A couple hundred bucks you can make your engine pretty reliable. I had my headstuds pulling the threads, blowing headgaskets, my stock clutch went away in about 4 races, the HD cam chain is cheaper than the stocker so why wouldn't you use it instead? :huh

[Knips178]

what heavy duty cam chain are you buying? what the crf chain?

[UglyMotha™]

Originally posted by 400exrider707
Personally I would stay away unless you plan on doing the "works" to your bike to compensate for the 440. Like hardfacing your rocker, heavy duty cam chain, oversize head studs, and probably an 8 plate clutch setup. JMO



what does hardfaced rockers do for a 440 other than destroy the cam if your not using them with a cam that is hardwelded, hardened rockers do nothing for reliabilaty, only time they are needed is if you use a cam that is a regrind that had been welded :huh


a crf chain makes for a good heavyduty chain, it is identical to the 100 dollar heavyduty chain engine builders sell, same number of links and plates so why not buy a 30 dollar chain that is identical to the 100 dollar chain

[ZSK]

Originally posted by Knips178
what heavy duty cam chain are you buying? what the crf chain?

Yup the CRF cam chain, UglyMotha said it right. It's the same chain that builders sell as HD.

[Knips178]

The cam chain is not the same! I've heard this argument a hundred times on these forums that they have the same number of links and are identical. They are not identical. Call any big name mechanic like sparks, ct, etc. and they will tell you that the pitch of the chain is different. But most people manage to make it work just because it is close. I tried the crf chain personally it didn't work right so I called sparks and others only to find that none of them ever used those chains because they aren't the same.

[UglyMotha™]

Yah if i was an engine builder selling a 30 dollar chain for 100 bucks, i'd tell you the same thing too

been running the crf chain in my bike for over a year now, just split the cases the other night, chain is in good shape, and the stock sprockets are showing no wear let alone any abnormal wear, the only problem i have experienced is a timing chain tensioner failure and that would happen with any chain

[Knips178]

Yeah, that's why. Cause Curtis sparks sells so many HD 400ex cam chains that it's really worth ruining his reputation as an engine builder to lie. That makes perfect sense to me.

This is the same tired *** reasoning that you can find in 50 threads across exriders when you search for crf cam chain. Tell you what, buy all that crap and make your quad bullet proof like uglymotha says and i'm sure your quad will never have another problem. Good luck!

Oh by the way, the cam chain tensioner died in mine to after i installed that crf cam chain........then the whole engine blew up because of it and I wasted over $1200 fixing it. Have fun!

[UglyMotha™]

boy you hit that nail on the head........ i'm running the crf chain i guess that's why my engine has gernaded three times in the past two seasons :rolleyes:


my oppinion your problem sounds more like user error :o


for the record this is my second timing chain tensioner and the first one that went it was on the stock chain, so once again i doubt the chain had much to do with that

[400exrider707]

I too am running the crf chain and have had no problems whatsoever......... Also I read that the timing chain tensioners should be replaced every 100 hours, because they can and do fail.

[Knips178]

Yep, your right it was user error. I made the error of ever trying to put a cam chain from a completely different motor into a quad motor it didn't belong in.

Anyway, he'll do what he wants and I'm sorry I hijacked the thread and ranted about something that none of us will agree on.

But, the quad will have a ton more power than stock.

[markk]

I asked this question last winter, I would honestly go with a 416=(87mm bore) or a 440 stroker, (4mm crank 87mm bore)

The guy that travis bought that plactics from has a 440, and has had alot of issues with it, U should talk to him. But then i rode his 440, with the works, and then i rode my 416, His 440 did make for tourge, But my 416 snaped harder than his ever thought of! a 416/ or even a 406 are both good motors, and they will last a long time! With the 440 you luggin that big old piston up and down on that stock rod! Its gona cause alot of stress expecaliy down the road.

Patte440 has an Edelbrock carb for a 400ex!

[Plante400]

i installed wiseco 11:1 piston with my 440 kit and the thing has massive bottom end

Just witht hat one mod my bike owns Z's.

i dont have a cam or after market filter.

[redlined94]

I've thought about a 416 before and almost want one of those. How hard is it to do these kits yourself? Do most of you guys have it done or do it yourself?

[QuadJunkies]

Originally posted by UglyMotha™
what does hardfaced rockers do for a 440 other than destroy the cam if your not using them with a cam that is hardwelded, hardened rockers do nothing for reliabilaty, only time they are needed is if you use a cam that is a regrind that had been welded :huh


a crf chain makes for a good heavyduty chain, it is identical to the 100 dollar heavyduty chain engine builders sell, same number of links and plates so why not buy a 30 dollar chain that is identical to the 100 dollar chain

I agree on the rockers.. Dont need them... I have a 440 and a 426 for a back up just in case I ever need to change it out ... I havent got to fully test out my 440 yet but I LOVED my 426ex :cool:

[markk]

Tina is correct about the rockers, and How do u like your 426??



Redlined94- Our 400 motors are very very simple man u can put that kit in yourself im sure. The only thing u might want to let somone do, Is bore/hone your cylinder, and mabey Have that same person do a valve job on it! Porting is also pretty good!



There is a guy that does great work down in Ashley/Radom IL. Ill send u a PM and send u his # and name if u want?

[QuadJunkies]

Originally posted by markk
Tina is correct about the rockers, and How do u like your 426??


I have had no issues with it whatso ever ove the year Its been installed, it was sumply worn out from ALOT of races and fun rides.. Thats why Im keeping it for a back up.. I LOVED iT! I just coudl use more on top so we shall see how my 440 is!!!

[redlined94]

Explain the hole point of boring it out. I thought the new sleeve that came with the kit took care of that or maybe I am just totally confused on how much work has to be done. Sounds like the 416 or 426 is the kit to go with though!

[foleyit]

On the 440 kit you need to have your barrel re-sleeved. Now if you go with a 406, 416, or 426 you can use your existing sleeve. But you will need to have it bored to fit the new piston size.

I am real happy with my 416 kit. I went with the Sparks 12.5:1 compression piston. The 416 piston is lighter than that of the 440 and as a result your throttle reponse is snappier. I had a local shop bore my barrel, and a had the head ported by a friend with experience in this area, but I took the motor a part and put it back together myself. In addition, to your standard tools make sure you have a torque wrench and a rubber mallet on standby.

[redlined94]

how do they bore out the sleeve, is it like a special drill or something or how is that done? How much does a sparks kit run for the 416 kit and how much for a 426? You guys are helpin alot thanks!!

[foleyit]

You plan on tearing your motor down and putting it back together too?

http://www.sparksracing.com

[markk]

Originally posted by redlined94
how do they bore out the sleeve, is it like a special drill or something or how is that done? How much does a sparks kit run for the 416 kit and how much for a 426? You guys are helpin alot thanks!!



The bore setup that i have sceen done was all on car motor, But it cant be that much diffrent im sure, Well have u ever sceen a brake laith (sp). It has some really really tough tips/blades and they will set the machine up to fit directly into the center of your Jug, Then the shaft coming outa the boring machine will spin at a steady motion and it will run itself at a set spead threw the cylinder moving in a downward motion very slowly. But to set the machine up alot of times the Tech. likes to have the piston and make sure the mesurments are all correct.

i think a stock bore is 85mm, and a 406 Im not sure of, mabey 85.75mm, and a 415= 87mm, and a 426=89mm and a 440 =91mm (i think?)

The only thing bad that im gona say about a 426 is that it has a heat issue! Your cylinder will be punched out as far as it will go, whitch leaves u will very little steel left inside your jug. Its a great motor for tourque and RPMs But say your motor is caked in mud and your just trail riding real slow it has a possiblity of over heating!