I'm looking for some help. I'm thinking of getting an Athena 435 kit and a Yoshimura full system ( RS-3 series or TRC?) . Your'lls thoughts?. I have a stock 04 Z400 and am having trouble keeping up with my buddies who have 450's and stroked 400 EX's. Any other go fast goodies? (Lid,Rejetting?) I ride mainly trails and some open country.

Thanks for any help.

 

I have a Yoshi Comp (RS-3) Full system and re jetted carb. Was a huge inprovement, but not enough to keep up with the TRX450.

 

id say go for the 435 and the full yoshi, with a stage 2 dyno jet also.

also, if you really want to keep up, get the stage 2 hotcams(intake and exhaust) and the drz-400 springs and valves and that puppy will riiiiiiip.

 

and actually while u have the head off u can give it a little port and polish job with some sandpaper.

 

if u start playing in the motor, dont mess with a jet kit. find a yfz 39mm carb on e-bay. so.... much better!!!! got mine for 150 off of e bay. suz. should have put a 39m on in the first place.

 

Carb is definetly a very good upgrade. Like KAWIKING said 39mm fcr from a yfz would be the way to go.

You would also want cams with the big bore. Get both cams, either brand Webb or Hotcam.

With my mods in sig (no big bore) Im running with piped 450's.

DRZe springs are stiffer, but the valves are the same as the Z.

You might also want to replace the timing chain with hd chain.

I wouldnt mess with the porting unless you have someone who knows what their doing(flowtest) port it.

Woodwardspecialties and advantagecyclelc both have some good prices and service on cams and/or big bore.

 

Thanks for the replys, just ordered my Yoshimura system (RS-3). I think I going to wait on the others and see what the pipe does for me. Thanks for the suggestions again.

 

I was wanting to know if i should put a 435 kit in my ltz 400 its piped and has k&n filter thanks.

 

If i put that kit in my ltz 400 would it start to have engine problems.