stock for stock 400ex-z400

[wildchild2]

Went to little sahara in wynoka last weekend and raced sevral mostly stock(slip on) and beat them. My buddy that went with his 690 raptor BLEW up on friday night so it was me his brother in law and his friend that I was with.I've never seen the same ambulance that many times in the same day as by the south gate. Had a blast didn't crash wheeled for ever and nothing broke.

[frosti108]

well i heard the z400 is faster. it makes sense since its liquid cooled and all. plus its brand new technology they have invested in it while "they say" the 400ex is ancient. but still the 400ex is way ahead of the 300ex in design so yea :o what am i getting at? nothing im just babbling for no reason because its late and im bored. sorry :huh

[devildriver422]

there are 2 reasons the z is faster...cam, and piston....the piston compression on a ex is 9.1? correct me if im wrong and on a z its 10.1? again correct me....so if you put it a piston that has the same or higher compression you should about keep up...then theres the cam, on an ex its a tame cam thats meant more for trails and on the z its meant more for racing...so replace those 2 things and youre faster

[wildchild2]

I probably didnt say it right but I was riding the 400 ex. The guys I raced were about the same weight and height as me but on z400 and kfx 400s. I wasnt the only one to beat them. There were maybe a handful of ex's that beat these guys but I don't know what was done with these. Remember were talking a really short race like a 16th mile.

[cals400ex]

the z's compression is actually right at 11:1 stock


with that short of a race, the driver is what matters most.

[440ex2001]

The z's also have double over head cams.

[Billdog350]

The 400ex has a bit more torque down low than the z400. I have had both (I have the z400 now) and I noticed right off the bat that the 400ex had tons more low end. If you were doing short drag races, the torque of the 400ex might be helping you win over the z400. However the z400 has WAY more top end power out of the box and with the airbox mod and some jetting, you're better all over the powerband than the 400ex.

I liked the smoother and higher revving z400 motor over my 400ex motor, however the 400ex is reliable and there are tons of aftermarket mods available.

It really comes down to if you want reliability, performance, and for what price. The z400 has REVERSE which is NICE to have and the liquid cooling and twin cams respond better to performance mods than the air cooled SOHC of the 400ex.