The Grey Wire and Starting with the Button

Anyone notice a reluctance to start with the Button once the Grey Wire is Disconnected? Mine seems to turn over rather slow, and yes, the Battery is fully charged. The Service Manager at one of the Dealers drew me a graph of the timing difference when the Grey Wire is unplugged and the way Yamaha described it to him was that the Grey Wire only affected timing in the mid range,apparently this was so that if someone pulled the stock exhaust baffle and cut the Throttle Stop and did not re-jet, the bike would be way too lean at part throttle.The backed down timing would prevent meltdown in this scenario. Any input/ideas on this? I know my bike had a part throttle cruise surge (lean) with the baffle out and throttle stop cut before I even pulled the Grey Wire.

There should be no difference. Has the weather changed? Jetting? I have not heard of this as an issue. :)

I've had three WR Yammies(400-250-450) I cut the gray wire on them all. Never noticed a starting problem.

Try cracking the throttle about 1/4 before you hit the button. Should fire right up. :)

Well, here's the scoop. When using the stock exhaust with the Baffle out or the YZ tail section (stock jetting), it started fine. I then pulled the Grey Wire and changed the Jetting to the specs below in my Signature, and with the YZ tail section or my new Big Gun Exhaust, it turns over slow. It seems like you are on the right track asking about jetting, I need to open the fuel screw, it's still at stock setting. I would bet money that this is a problem. With regard to the "Starter Jet" posts, if I am correct, the Starter Jet is only operational when the Choke is pulled out,right? Thanks for putting your thinking cap on, made me re-think that which I already knew. I gotta get me a Zip Ty fuel screw since from what I have heard, the fuel screew setting changes from day to day. It still seems like the Starter is turning at a lower RPM than before though.I do think it would "catch" quiker if I open the fuel screw a bit regardless of how fast it's spinning over on the starter motor. It has always started well with the kicker, although now it's not as good as it was before exhaust and re-jetting.

mine runs just fine the way it came...

Yes, that seems to work at least from my preliminary attempts in the Garage....BUT.....That is not the best idea due to the potential for a backfire and subsequent sheared Woodruff Key on the Crank-Flywheel that the $7000 WR is so famous for. I LOVE the bike, just wish it would hit everytime on the button like my buddies KTM does. Although, I can fix the starting problem, most likely with Jetting. He is stuck with KTM's linkageless Suspension in the back that STILL does not work right after much tuning. I'll stay on the BLUE BIKES tahnks........

Mine ran just fine "the way it came" too. The problem is, it was choked down and slower than a 250 with the throttle stop and Baffle. Glad you are happy with it "the way it came" but I am trying to keep up with KX 500's on mine.And I am getting closer.........

I just kick start it before the first ride,the rest of the day the button works great!!! I did notice easer starting with the z-tye fuel screw in and having it adjusted right.I also did everything but the grey wire.

Back to that Zip Ty screw. I'm gonna call Ty and have him bring one out to the Race this Weekend for me.Seems like a solution to the problem.

Thanks for the info!

How cool is this:

Just called Zip Ty Racing, asked if there was anyway Ty could bring out the screw to the race. They took my Card over the Phone and told me to find Ty (How hard is it to find a Semi That says "Ty Davis-Montclair Yamaha") and he would have it! Now THAT my freinds, is REAL Customer service!

On my WR I had to twist the throttle 28 times to get it to start. I opened up the starter jet. I use a micrometer and a numbered drill set. Non-cheapskates use a #72 starter jet. I also use 2-1/4 turns on the fuel screw.

It now starts instantly if not sooner.

Why did you change the Starter Jet? Would your Bike not start with the Choke on? The Starter jet only affects the mixture when the choke is pulled out, right?

I had a cold starting problem with my bike when it was still cold out(below 45 F.). The local Yam shop ended up drilling out the choke jet to a #80 and now it starts up great. The stock choke jet on the WR450's barely richens the mixture at all. I also had the dealer install a new battery (no charge) because mine would lose its charge too fast. My new battery and jetting work great now. I don't even touch the kickstarter unless I want to show someone how good the autodecompression works.

CowboyBob ,

Red loctite is like JB Weld. No Worries. :)

The starter jet only works when the choke is out.

Were is the grey wire on the 2000 Yamaha WR400

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