My official build thread!

[Zakradu398]

I figure I'm a good way through it to start one of these. So here we go!

So it was my 17th birthday and my Dad told me he'd buy me tires and rims for my '99 Wrangler. That was sweet, but then I happened to look on a local Yamaha Dealer's website because I knew they were going out of business soon. They had an '04 400ex on there for $1400!! I thought it was a misprint or there was something wrong with it. So, I told my Dad and since rims and tires would cost the same, we went and took a look at it. Looked nice, rode fine, but needed tires. We talked them down $50 and got it for $1350.

Here's the pic they had on their website.


I got it home and rode it for a while. I'd shut it off and then the fuse would be blown, so it wouldn't start. I then realized that was why it was so cheap.
Now, this is my second quad besides an old Arctic Cat 90. (I rode dirtbikes) So I tried diagnosing the problem. Turns out there was a bare wire grounding out on the frame and a 2" piece of electrical tape later I was set.

I then flipped it the same day doing wheelies and bent the bars. I went ahead and ordered Tusk bars and Polisport roost deflectors.

[Zakradu398]

I started browsing craigslist for any aftermarkets and came across a Yoshimura Comp slip on listed for $150. I felt that was a damn fine deal so I went and picked that up. I also got anm Ebay PB block, 757 brand?



After that, my friend was selling a powerbomb header from his 400 but I was cracked by the "bomb". My GF's Dad is a welder, so he patched it up for me.



Next came some 450r shocks, they don't look the best but work just fine for me. I'll be in the market for new shocks this next payday

[Zakradu398]

By now, I rode it for about 5-6 months and the tires were still horrible and I beat the living hell out of the stock rims. The clutch also started slipping so I got 4 gbc x rexs, black ITP BAJAs, uni filter, swingarm bearings, and a Tusk HD clutch.

[Zakradu398]

The swingarm bolt was a NIGHTMARE to get out. We had to cut it out, but it was still stuck in the motor bushing. MY friend who is an Arctic Cat dealer also has a shop so he drilled it out of there for me.

Here's how I ended up cutting it out.



During this time I also ordered GT thunder +2 A Arms.




It was now summer and I started doing a lot of night riding, So I read the sticky and went ahead and bought the DDM Tuning HIDs.


Here is a middle of the day shot.

[Zakradu398]

I broke off my back brake caliper mounts because a bolt had come out, I was drifting backwards, hit the back brake and it snapped. So I ordered a new one of those.



I want to do a few harescrambles this year too in the AWRC Series, so I got a Tusk Tether.



Here it is at that point, I got a moose case saver too because I had $50 free on RMATV

[Zakradu398]

My motor started leaking oil from the Rocker Arm Shaft washer on the head. So I was about to start tearing it down, but I went to ride one last time and it started blowing smoke pretty bad. I didn;t end up going out that day so I tore it all down.

I sent out my cylinder today to be bored and I ordered a Stage 2 Hot Cam along with a 11:1 Wiseco 86mm piston.

This is my first time tearing down a 4 stroke motor. MY Dad says I'm gonna end up messing something up so I should take it to a shop. I had to tell him I don't believe in that and to sit back and let me prove him wrong.






Notice the blood by the dowl pin, I cut my finger on a piston ring








My cylinder, cam and piston will be in on Saturday.

[AtvKid4Eva]

Bike looks awesome man! If theres one recommendation i can make thats to send the cylinder to GT Thunder and get the HD head Studs put in for around $100. That way when you reinstall it you dont blow head gaskets from the studs stretching. They dont like to be reused once you take them apart. If you have any other questions PM me and im sure i can help. Ive built many many 400ex motors. You can also text me 216-536-1500.

[Zakradu398]

Thanks for the idea man, I'll take your number down too if I have any questions or things. CJM has taken care of me so far

The stud thing though, I planned on doing that over winter because I will probably go up to a 12.5:1 piston on Avgas and get my head ported at the same time.

[AtvKid4Eva]

Sounds good. It just sucks to get the whole motor back together and then have to re tear it down because of the studs. Just text me anytime if you need any info.

[Zakradu398]

I just ordered a few bolts I was missing along with a Tusk Frame skid plate and 5 extra oil filters.

A guy on my local CL has AC blackline nerfs he is selling, it says $120. Is that reasonable or no?