Just purchased a 2000 yz426, any advice??

Great looking and running bike but starts like a POS :)

The bike has a full FMF exhaust and the seller also gave me some contraption to install on the carb. Any tips guys on that or any other things I should do to the bike??

hey are you willing to sale the pipe if so how much and what kind of fmf is it

I know its been said 1000 times before, but if your bike doesn't have it already, put the auto decompression cam in. The number one must have for the 426. The bike will go from the worst starting machine in the world to the easiest.

Check the valve clearences.

Check ur valves bro, they are probably too tight

Check the valve clearances and change the plug. Should fire right up.

Probably worth putting in a new timing chain if it hasn't been done yet.

know its been said 1000 times before, but if your bike doesn't have it already, put the auto decompression cam in. The number one must have for the 426. The bike will go from the worst starting machine in the world to the easiest.

Pfft. How hard is it to pull the decomp lever?

The exhaust has a power bomb header with a power core IV2 muffler. I want to keep this system for now.

Rumaging thru the box of parts the seller gave me I found the carb gizmo, a P-38 Lightning pump plate and a Power now. I have no idea why the seller didn't install these two gizmo's. Should I and what improvements do they make? I'm gonna let the bike warm up in my shop and then try to start it. The seller warned me that if it was cold out it doesn't like to start. Fortunately I don't ride in these temps.

I know its been said 1000 times before, but if your bike doesn't have it already, put the auto decompression cam in. The number one must have for the 426. The bike will go from the worst starting machine in the world to the easiest.

How much for the cam? I don't have a big problem starting mine but I'm always looking for better products.

do you have any sprockets for sale

How much for the cam? I don't have a big problem starting mine but I'm always looking for better products.

I paid $150 for mine from Hotcams, but you can buy the YZ450 cam for likley $70 bucks cheaper.

The 2000 model has the jetting way off.

You need to do three things here:

1) purchase or make an extended fuel screw (zipty, MSR or ebay, etc)

2) purchase a JD jetting kit. Best thing you can do. Alternative you can use the AP diagphram, jets and needle from the 2002 model year bike, but the JD kit works better

3) do the BK mod on the AP and set it properly. stock the AP floods out the motor.

450 cam mod is a must! Just did mine last week. Got the cam at North County Yamaha in San Diego for $96.

Both are great mods, I am running both on my 02 426, the powernow will mellow out the hard hit, and the P-38 will get ride of the bog when you crack the throttle, a must when adding a pipe!

Buy the summers seal savers if you do any kind of trail riding. They will save you a lot of time and money. Buy the long ones.

Keep the oil changed and the filter clean. I recommend buying a Scotts stainless steel oil filter, so you have a filter you can clean and reuse, but still filters better than brass or paper. If you change your oil every 10 hours or less like I do, the Scotts will end up being cheaper than $5 bulk paper filters in less than a year anyway.

The '00 426 is a brick. Except for a few things that needed refinement, like the clutch, the thing resembling a weak link they have is that the balancer shaft gear is located by a key, rathere than splines as the later models are. If you start to hear a disturbing rattling from the bottom end, check there before you hit the panic button.

The '00 used stainless valves instead of titanium, so they're a bit longer lived in that regard, too.

Starting can be mastered, although I do recommend the auto decomp cam mod. Yamaha has a video I can link you to later, I don't have it here that explains the procedure very simply. The biggest part of the trick is in positioning the engine. Run it up against compression and take the pressure off the kickstarter, but don't move it. Pull the compression release in and push the kick crank down just about an inch. Let the release go, return the crank to the top and give it a full smooth kick through with no throttle, or very little. Do not twist as you kick the way so many two-strokers do. With the release, you are trying to get past the first 1/2 to 2/3 of the compression stroke, but not the whole thing. You kick it through the last third, and it should fire.

The valves may be to tight, check them and give her a new plug.

Thanks for all the idea's guys :)

I have my 2000 426 since it was new and have had no problems. Did the clutch mod,flywheelweight,blue wire mod ect. I can start my 426 faster than most guys with the auto decomp. To me the cam mod would be a waste of time and money.

. To me the cam mod would be a waste of time and money.

I thought that b4 I made the decision to go auto decomp!!! you might think that its a waiste of money or time but I assure you it isnt..Dont be stubborn,go with the modern techno flow :):)

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