Engine mods to the Z

[KILLSWITCHngage]

I am starting to think about getting a 450 kit for my z400. Need some info ect on what u guys have got, prices , ect. I race xc.

[CFRacer03]

I have a Z450, built by my local engine builder here. I can't remember all the specifics, but it's been bored and stroked to a 450, ported, cams, everything, also a FCR39 carb. I think it cost me about 2500 all together. It made a huge difference but it would be hard for me to justify doing it again, now that all the new bikes(450r, 450z, yfz450) are running with it almost stock. If you don't want to spend that much money though, I would recommend the carb $400, cams $200, and a port job $300 and you'd see a huge difference, and maybe a high compression piston. with that you could get out for about 1000 and you'd feel a world of difference. plus I'm assuming you already have an exhuast, just cause thats one of the first things people get...

Where are you from in AR? if its the northern part I can recommend you to a guy that does a real good job, right outside the Mem, TN area...

[KILLSWITCHngage]

Russellville. about 2 1/2 hours from memphis. thanks for the info . i might be interested in it when i am ready for some motor work. thanks

[IrideMHSC]

Im runnin a 470 kit but with stock cams and all that... its definately alot torqier through the woods and stuff and i can lug in 2nd and 3rd and come out of the corners with good speed. it was pretty expensive but i nikalised the sleeve sna stuff so aroun 1500 to 2000 i think

[BLACKZ400]

IVE HEARD THE CAMS ON AZ REALLY DONT DO THAT MUCH IS THAT TRUE AND ALSO WHAT KIND OF CARB DO U RECOMMEND.AND ALSO CFRRACER WHO DID U TAKE URS TO FLETCHERS

[CFRacer03]

BLACKZ400. no, I don't care for Fletcher's. I took them a banshee motor once to build a drag bike. Three months later I went up there to see what was taking so long (this is after I've talked to them on the phone a few times, they tell me about progress being made...blah blah blah) and the engine is sitting EXACTLY how I left it, hadn't even been taken apart, they hadn't even ordered parts! THREE MONTHS they had my motor! plus just being in the quad/dirt bike/street bike/ etc sceen, I've never even heard much good stuff about Fletcher's work.

I had Jeff at Maximum Cycle in Millington build a 416EX, 400cc Banshee, and my Z450. They were all good bikes, he does great work.

about the cams...I had Jeff put in cams(Webcams) and an FCR39 carb before he fully built the full motor a few months later and I saw a pretty big difference with just those two things(along with the exhuast I already had)

But my most recent bike's engine, 06 450r, is at Sparks right now, THAT is going to be an engine, I can't wait to ride it.

[BLACKZ400]

YEA I HAD JEFF JET MY BIKE I REALLY LIKE HIM HE S A SUPER NICE GUY SO HOW MUCH FOR CAMS AND INSTALL. ALSO WHERE DO U NORMALLY RIDE AT

[CFRacer03]

I really can't remember, that's been two years ago now. I'd just call Jeff and ask him 901-872-8676. I'd estimate about 800 with parts and labor, but I'm really not sure. An FCR carb is about 350 I think, cams 200, then some little things, gaskets, etc. and labor costs, but don't hold me to those prices...

I actually live in Oxford, MS now. I'm going to school at Ole Miss. So I really don't get a lot of time to ride. But we used to mostly ride the local MX tracks around there, Dry Hill, Thrill Hill, Hidden Valley, a few others. But last year we got into TT and raced a few of the national series races TT races and we are planning on making that whole series this year...

[HondaRider250]

if i put a high-compression piston in my kfx (13.5:1) do i gotta run race fuel?

[CFRacer03]

yes, usually 12:1 people start using race gas. you at least need to mix 50:50 when you're just ridin trails, goofin off, whatever. but if you're racing the bike I'd run all race gas(110+ octane) during a race...I've been running race gas in everything so long I could be a little off on those numbers, somebody please correct me if i'm wrong

[djm137]

I run a 13.1 VCP Hammerhedz piston (stock base gasket), and I run a 50/50 mix of 93 pump and 110 cam2. it works fine. I was told i need to keep the octane at or above 97 for this compression and also to run straight ras gas for 14:1 not sure about 13.5

ps a lot of people just use the thinner drz base gasket to bump the compression up from 11.3 to around 12.2. This only requires 93 octane as far as i know