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Pappy
02-13-2004, 03:58 PM
can someone walk me thru the process:confused:

str400ex
02-13-2004, 04:07 PM
yfzcentral has a step by step guide on the cam mod with pics, also a good place to look for jetting specs.

Pappy
02-13-2004, 04:08 PM
sorry, i cant post at other sites:o its in my contract:p

Maxx_Action
02-13-2004, 04:40 PM
Cam Mod Vids...

www.eskimo.com/~daddog/index.htm

Maxx

BigAl
02-13-2004, 04:54 PM
1. line the motor up on TDC.

2. remove cam chain tensioner.

3. remove exhaust cam cap WATCH THE HALF MOON WASHER IT IS MAGNETICALLY ATTRACTED TO THE CRANKSHAFT!!!!!!

4. rotate the exhaust cam 1 tooth backwards, so that the timing mark that should line up with the top of the head is slightly higher than the valve cover/head mating surface.

5. put it back together and ride.

You are pretty mechanically inclined right? It's real easy to do.

As far as jetting goes???????? somewhere between 168 and 180 mains, and 45-48 pilot. NVCQ needle from the YZ 450 F

Jetting is kinda like toilet paper, you gotta go with what feels best to you. :D

Sick0
02-13-2004, 05:36 PM
Just make sure you put a rag in the cam chain hole. Watch out for the half circle ring that holds the cam in place.

Bad Habit
02-13-2004, 06:04 PM
Originally posted by BigAl
Jetting is kinda like toilet paper, you gotta go with what feels best to you. :D


LMFAO, that's the best one I've heard yet. I'm gonna use that one for sure.

Baley69
02-14-2004, 03:18 AM
I have to find out if it voids my warranty. If it doesnt I'm going to do that along with my woods intake and pipe.

brif
02-14-2004, 09:00 AM
go to gtthunder's website. Click on yfz and on the page with the dyno graphs you'll see a link for "cam mod".

jarsong
02-14-2004, 11:10 AM
Originally posted by BigAl
1. line the motor up on TDC.

2. remove cam chain tensioner.

3. remove exhaust cam cap WATCH THE HALF MOON WASHER IT IS MAGNETICALLY ATTRACTED TO THE CRANKSHAFT!!!!!!

4. rotate the exhaust cam 1 tooth backwards, so that the timing mark that should line up with the top of the head is slightly higher than the valve cover/head mating surface.

5. put it back together and ride.

You are pretty mechanically inclined right? It's real easy to do.

As far as jetting goes???????? somewhere between 168 and 180 mains, and 45-48 pilot. NVCQ needle from the YZ 450 F

Jetting is kinda like toilet paper, you gotta go with what feels best to you. :D

You will also need a quality torque wrench for this operation. It is very easy to do just make sure you follow the steps in the video posted in this link from Daddogrider. Also carve out a good piece of time to do it in and DON'T rush. Make sure your bike is as clean as a whistle. I did mine with less than 5 minutes on the bike and hadn't seen the dirt yet. I finally got to take it out on our track 2 days ago and all I can say is WOW. It will lug down like our Z400 now and pull hard to the rev limiter. I now see why the dirt bike only has 4 gears. with the power produced 5 aren't needed.
www.eskimo.com/~daddog/index.htm

My jetting is as follows.
275 foot elevation, 55-60 degrees....
168MJ
45P
You HAVE to go get the YZ needle (NCVQ)?? Mine is in the 3rd position.
2 turns on the fuel screw
Mods are :
Cam mod
Pea shooter removed
GYT-R air filter with the lid off.
With is jetting it will also run pretty good corked up wiht the air box lid on and pea shooter in...
jarsong

raptor_02
02-14-2004, 12:08 PM
I retimed my exhaust cam and I couldn't get my quad to start. I have a 13/1 piston, 172 main, 45 pilot, and i'm around 1200 above sea level. I put it back to stock timing for now but plan on doing it again soon. Did any of u have trouble starting your quad when you did the cam mod?

jarsong
02-14-2004, 01:36 PM
Originally posted by raptor_02
I retimed my exhaust cam and I couldn't get my quad to start. I have a 13/1 piston, 172 main, 45 pilot, and i'm around 1200 above sea level. I put it back to stock timing for now but plan on doing it again soon. Did any of u have trouble starting your quad when you did the cam mod?

No and funny thing is it started like I never touched it. WOnder what the deal is.
jarsong

norcal.z400
02-16-2004, 11:15 AM
Originally posted by raptor_02
I retimed my exhaust cam and I couldn't get my quad to start. I have a 13/1 piston, 172 main, 45 pilot, and i'm around 1200 above sea level. I put it back to stock timing for now but plan on doing it again soon. Did any of u have trouble starting your quad when you did the cam mod?

you probably turned it the wrong way

raptor_02
02-16-2004, 02:25 PM
no i turned it the right way i am positive. I'm thinking maybe we may have retarded it two teeth instead of one. But we are getting ready to try it out again soon so hopefully everything will work out ok.