400ex build.

[Baxter]

http://i739.photobucket.com/albums/xx34/Baxter58/Fun%20Stuff/Margate2013-1-2015-2_zps78e8b53d.jpg


http://i739.photobucket.com/albums/xx34/Baxter58/Fun%20Stuff/Margate2013-1-2001-2_zps60177108.jpg


I got a 400ex because of the the problems , I was having with the 700xx .

Kinda of putting it out there but after searching for far too long did anyone do anything than put 450r bits on it ?

[CJM]

Not much you can really do if you race, not sure if you have engine restrictions or not.

Generally build that works the best is as follows:
11:1 piston, heavy duty GT Thunder head studs
Hotcams stage 2
04-05 450r carb
Slip on or full exhaust.
Open airbox lid with filter.

[Baxter]

There's no engine restrictions . They are starting an EVO quad and ATC Championship here in the UK and just wanted some input.

I always wanted a 400ex and the EVO series was a good enough excuse to buy one. Will be racing 250r's, Banshee's ,Quadzilla's and Tri'zs.

[RNL]

Originally posted by Baxter
There's no engine restrictions . They are starting an EVO quad and ATC Championship here in the UK and just wanted some input.

I always wanted a 400ex and the EVO series was a good enough excuse to buy one. Will be racing 250r's, Banshee's ,Quadzilla's and Tri'zs.

Awesome, enjoyed following your 700xx stuff and I'm sure your 400 build will be sweet as well.

[Baxter]

Originally posted by RNL
Awesome, enjoyed following your 700xx stuff and I'm sure your 400 build will be sweet as well.

Thanks the 700xx is good fun .

The 400ex will be used for xc,mx beachcross,ovals and a 8 hour XC.

I'd the motor to be strong enough to keep with a few 450's but stock or better reliability .

[Baxter]

Been playing.


http://i739.photobucket.com/albums/xx34/Baxter58/lil%20rex/400ex-1009-2_zpsc268c60f.jpg




http://i739.photobucket.com/albums/xx34/Baxter58/lil%20rex/rex004-2_zps1fe0dea2.jpg

[RNL]

So what motor mods do yo have planned? Exhaust, Sparks timing key? Going into the motor more?

[Baxter]

I have a 2 700xx motors to build first but I have alot of 450r/700xx parts so it may just get slightly modded. Big Gun exhaust and a Hot Cam.

On a side note did anyone build a bigger inlet manifold for the carb. I have an idea but it won't fit the stock one.Talking about the carb to cylinder head boot.

[gasguzzler]

There is quite a bit of meat on those factory intake flanges, I've hogged a few of them out to fit various carbs and port matched the intakes.

[Pittsburgh400ex]

Were you thinking about boring it over at all? A nice 11:1 416 kit is super nice and reliable. I had that and a 426, loved them both with my Sparks' full system and cam.

[Baxter]

I'd like a stock bore stroker.

http://i739.photobucket.com/albums/xx34/Baxter58/Frank/400ex-70182_zpsc0ddc4cb.jpg (http://s739.photobucket.com/user/Baxter58/media/Frank/400ex-70182_zpsc0ddc4cb.jpg.html)

Ideas.
Edelbrock, 04 450r,700xx EFI, CRF450r EFI. missing FCR from a CRF450r. It was suposed to be in the middle.


Also on a side note the 700xx flywheel is slightly smaller in diameter and a tad lighter. The stator has a differant bolt pattern also.