400ex 416 final checklist run through

[doublejz]

So I have everything sitting in front of me except the tensioner and cam but I'm getting anxious to get to work already.

Is there anything on the list below that I'm missing that I should really replace while I have it apart?

JE 416 Piston Kit 12:1
Honda OEM Valve stem seals
Kibblewhite Valve Spring Kit
Kibblewhite Valve Guides
Kibblewhite Titanium Retainers
Kibblewhite Black Diamond Exhaust Valve 30.00 mm 1mm Over
Kibblewhite Black Diamond Intake Valve 34.00 mm 1mm Over
Hot Cams Camshaft (Stage 2)
Cometic Complete Top End Gasket Kit
GThunder Head Studs
CRF450R Timing Chain
OEM Timing chain guide
OEM Tensioner
170-180 Jets

Whats the difference with the following? I want to replace the tensioner but I'm not sure which one I need or if I need to replace both?
14520-KCY-671 - LIFTER, TENSIONER
14511-KCY-670 - TENSIONER, CAM CHAIN

The only thing that I'm worrying about is the 12:1 piston. I don't see many people running that with a stock bottom end :-/

[CJM]

You realize 12:1 will mean 100+ octane right? Thats why most dont run them, 11:1 is usually the safe cut off.

14520-KCY-67 thats the spring loaded tensioner
14511-KCY-670 timing chain guide. You dont need it unless yours is worn.

Also you will need a valve job to run those oversized valves incase you already didnt know.

[LxMxL97]

Get the cam chain tensioner I always said when I'm putting that much money in it what's $60

[doublejz]

You realize 12:1 will mean 100+ octane right? Thats why most dont run them, 11:1 is usually the safe cut off.

14520-KCY-67 thats the spring loaded tensioner
14511-KCY-670 timing chain guide. You dont need it unless yours is worn.

Also you will need a valve job to run those oversized valves incase you already didnt know.

Yea, running straight race gas isn't a problem, I'm more afraid of the rod breaking or the crank giving up. Maybe I'll just grab a 11:1 piston and sell this one. *shrug*

So looking at this, I should probably grab numbers 4,6 and 8.
http://www.doublejz.com/images/forums/quad/parts.jpg

Yea, I know there is some machining to be done, p&p, valve job, gt thunder head studs install and maybe a 3 axis grind on the seats.

[CJM]

Yep 4, 6, and 8 are what ya want. I wouldnt replace the guides unless they are worn however.

[cheater13]

Not to hijack but since you guys were talking about pistons, what's the higest compression piston you can put in these 400exs? 13:1 maybe? I just haven't seen them anywhere.

[CJM]

Highest I recall was 12:1, race gas only I recall. Could try looking for an xr400 piston, might find something.

[jcs003]

i'd run the 12:1. race gas is better fuel and better for your machine as long as the gas is available and the dont mind the cost.

john

[cheater13]

I actually found out JE makes a 13:1 for our 400exs I'm pretty sure. :)

And no matter what, I'll probably be always running 112 octane.

[Stickman400]

Someone linked a 400 that was for sale on craigslist here awhile back and it had 15:1 compression. Believe it had a 13:1 piston, a xr400 head gasket and no base gasket with the head decked or something like that to achieve the 15:1. I wanna say it was a 450 or 465 too.

[cheater13]

Would a regular battery turn over that much compression?

[slightlybent47]

My results are as follows.

My build started with a stock 07 ex.
416 bore with 12.5:1
full race port and polish
2005 450 carb with choke plate removed (jetting) ah!!! I forgot!
xr 400 cam gear and chain
stage II cam
stock head pipe with welds ground smooth
WB MX4 slip on
over sized oil tank

I did this build back in 07 when the bike was new.
I didn't touch the head other then the porting.
Valves and guides, springs, all stock.
Crank case all stock.

I run strait VP U4.4 at 100% all the time.
I have no idea how many hours are on this motor but it's in the thousands not hundreds.
And these are racing hours, not riding hours.


Your build looks real good for a long lasting good running motor.

I wanted to ad that i only use the stock foam air filter with good foam oil and an outer filter over that.
Yes it does restrict the air flow just a "very" little bit.
But I'd rather have my motor last longer then one season.

Clean oil and a good clean air filter, goes a long way to a long lasting motor.
My EX is proof!

[cheater13]

How much hp you putting down?

[slightlybent47]

Only guessing, around 35 HP

[cheater13]

Only guessing, around 35 HP
Sounds like it should have more, haha. Mine is at 42hp. Hoping to get around 46hp on my 426 build after I'm done everything I wanna get done.

[jcs003]

Sounds like it should have more, haha. Mine is at 42hp. Hoping to get around 46hp on my 426 build after I'm done everything I wanna get done.

do you have a dyno sheet. its hard to get more than 40hp out of a 400ex. but you can get awesome torque numbers. espcially with the 440.

john

[cheater13]

do you have a dyno sheet. its hard to get more than 40hp out of a 400ex. but you can get awesome torque numbers. espcially with the 440.

john
I do but it has a dip in it since I had my old 450 carb on. He'll print me out another one when I pick it up tomorrow or Thursday at latest since I'm having a crf250 carb and my new HMF put on. I'll post it up then.

[slightlybent47]

I just made a guess. I've never put mine on a dyno.
Most HP from an 400ex that I have heard of is 52HP, But I didn't see the dyno sheet that proved it.
Whats the HP on a stock 400ex? I've heard it's around 27.

[cheater13]

do you have a dyno sheet. its hard to get more than 40hp out of a 400ex. but you can get awesome torque numbers. espcially with the 440.

john

Here's my dyno sheet I just got yesterday. Gained 4 hp with a different slip on and my crf carb!

And a stock ex has 28 I think.

http://i396.photobucket.com/albums/pp47/cheater13_photos/Mobile%20Uploads/image-137.jpg (http://s396.photobucket.com/user/cheater13_photos/media/Mobile%20Uploads/image-137.jpg.html)

[slightlybent47]

It really dosn't mater to me. Most of the tracks I ride on I don't need 60 HP. I still pass 450's on a regular bases all the time.
The only draw back is on fast tracks where high speed is needed. Then the old ex falls flat.
On tight technical tracks, the ex still can put down some fast laps if the rider is capable.

[slightlybent47]

I haven't posted any pictures of me and old red having some fun in a long time so here ya go!
There is 3 or 4 things different about the bike in the first two pics and the last two.
Can you spot whats different?

http://i62.tinypic.com/20h0tg3.jpg


http://i58.tinypic.com/1zf5uh4.jpg

http://i62.tinypic.com/2n8sxf.jpg

http://i62.tinypic.com/scqdrn.jpg

[mtsnieg]

Hard to see good on my cell, but the front numder plate is different.

[slightlybent47]

Hard to see good on my cell, but the front numder plate is different.

Good catch. Thats one!

[mtsnieg]

Front fenders

[mtsnieg]

No handguards

[slightlybent47]

Front fenders

Thats two!

[slightlybent47]

No handguards

Thats three!

Your doin great!:muscle:

[slightlybent47]

There's three more but there hard to see. Good luck!:D

[Stickman400]

Front fenders are cut
Handlebars are Renthals
Powermadd handguards
450R front shocks
Extended arms?
Front number plate
The gear you're wearing, lol

I think that's all of them, atleast from what I can tell.

[slightlybent47]

Front fenders are cut
Handlebars are Renthals
Powermadd handguards
450R front shocks
Extended arms?
Front number plate






The gear you're wearing, lol

I think that's all of them, atleast from what I can tell.

Awesome! you got them all!
Good eye!
I'm impressed, you got the a arms. lol

[Blodg]

It really dosn't mater to me. Most of the tracks I ride on I don't need 60 HP. I still pass 450's on a regular bases all the time.
The only draw back is on fast tracks where high speed is needed. Then the old ex falls flat.
On tight technical tracks, the ex still can put down some fast laps if the rider is capable.
I agree! Many people are fascinated with the straight-line speed of a 450 but I could care less if my 416EX is slower in a straight line because that is not the type of riding I do. I don't race anymore so of course there are many racers faster than me but I have found very few trail riders on 450's that can keep up with me in the woods. I also recently entered a hill climb competition that was not based on time but purely scored on whether you could make it up a series of knarly, steep, rutted, tree root hills with turns as you went up. I won the novice below 450 class but also scored more points than all the novice class riders in the 450 class as well.

[Blodg]

Here's my dyno sheet I just got yesterday. Gained 4 hp with a different slip on and my crf carb!

And a stock ex has 28 I think.

http://i396.photobucket.com/albums/pp47/cheater13_photos/Mobile%20Uploads/image-137.jpg (http://s396.photobucket.com/user/cheater13_photos/media/Mobile%20Uploads/image-137.jpg.html)
Cheater, I know you have a Web cam but I can't remember what compression piston are you running on that build?

[Blodg]

One last thing - awesome pics slightly bent!

[slightlybent47]

I agree! Many people are fascinated with the straight-line speed of a 450 but I could care less if my 416EX is slower in a straight line because that is not the type of riding I do. I don't race anymore so of course there are many racers faster than me but I have found very few trail riders on 450's that can keep up with me in the woods. I also recently entered a hill climb competition that was not based on time but purely scored on whether you could make it up a series of knarly, steep, rutted, tree root hills with turns as you went up. I won the novice below 450 class but also scored more points than all the novice class riders in the 450 class as well.



It's all about "usable" power.
Having the bars ripped from your hands when you pin it is fun and thrilling, but it's not always good to have.
Many riders insist on more power, but there not even using the power they already have.
Sure, there are time when more power is a good thing but fast lap times are not created from just a fast bike.
"TIRES" Fresh tires can make it seem like you have a new motor in your bike.

And thanks for the thumbs up on the photos.

[cheater13]

Cheater, I know you have a Web cam but I can't remember what compression piston are you running on that build?
Just a little 11:1 JE. Hoping to get one of those 13:1 JE pistons when I get my bigger Web cam.

And yeah, awesome pics slightlybent. I would love to have a 400ex to run mx with. I went the drag route on this one though. :p

[CJM]

True, faster isnt always better. Friend had a DONE UP 06+ 450. Talking 65+hp, it would rip your arms out of there sockets! Too bad it had little useable power unless it was wide open. Any of the tighter spots I easily passed him with my 50hp 450. Also rode the done up 400 for years and it had plenty of power, but still not as torquey as a 450.

I still think I had the most fun on the 400, the tractor like power is something the 450s dont really have/

[slightlybent47]

Thanks guys for the complements.
The first pic is at Cycle Ranch in Florseville Tx on there new night track. Shot last month 2014
This was the first time they let quads on that track and I was the first bike out there.
If you live in TX you gatta ride this track.
There main track is 2.4 miles long and is just as sick as there new night track.


The second pic is a new track in Anderson Tx called Battleground.
That pic was the grand opening weekend. That was last year in 2013.
You cant see in the pic but T brown is stalking me. lol

The third one is also Cycle ranch but it was shot in 07.

The last one is at Three Palms in Conroe Tx where we ride most of the time. this was back around 2010


The best thing about riding the 400 is durability. I built my motor in 08 and she has thousands of hours on her and she still rips.
Everyone that rids a 450 has had to fix the motor at some point before the bike is 2 years old.
Sure you can over build a 400 and the durability will go out the window. But if you build a slightly modified ex she will run great and last a long time.

The motor hasn't been touched since it was built.
Can say the same for the chassy.
I broken a Durablue heavy duty axle.
I broken the tie rods.
I droke the knuckle on the a arms.
Bent the steering stem.
Bent wheels.

[slightlybent47]

Here is the promo vid for Battlegrounds where T Brown is stalking me. lol
Me and TB are 0:20 sec. in on the video.
http://vimeo.com/84837944

[MoparMadness]

Doublejz I've had the same setup as you are describing and let me say its an awesome setup there's only one problem that I have found wrong with this setup and that is that JE Piston will not work with +1 intake and exhaust valves and that is because they do not cut the combustion chamber right to allow for the bigger valves. My valves hit the exhaust side of the 87mm piston unbeknownst to me until I had to tear it back apart. Didn't know what went wrong at the time so I ordered the 88mm JE Piston (426ex) kit. My crank locked up so I had to tear everything back apart again :mad: lol then realized valves hit exact same spot again thank goodness my valves are fine. No more JE Pistons for me going back to the trusty old 87mm wiseco piston. I hope im not to late to tell you this and hope what I found out will help other's in the future

[MoparMadness]

If you have any other question's feel free to ask away. :D

[slightlybent47]

I agree! Many people are fascinated with the straight-line speed of a 450 but I could care less if my 416EX is slower in a straight line because that is not the type of riding I do. I don't race anymore so of course there are many racers faster than me but I have found very few trail riders on 450's that can keep up with me in the woods. I also recently entered a hill climb competition that was not based on time but purely scored on whether you could make it up a series of knarly, steep, rutted, tree root hills with turns as you went up. I won the novice below 450 class but also scored more points than all the novice class riders in the 450 class as well.


Awesome! Keep rippin!