I am new to all this so please bear with me, I've just bought a 2005 wr 450. It come with a scorpion can (not my first choice of exhaust). Ive removed the grey wire and the exhaust baffle. From what i can tell it runs sweet altho a lot of popping on deceleration (to be fair my 2011 r1 is the same no cat mapped ect). Kicks over easy first kick when cold with choke or couple of secs on the starter.
For my first run i took it about 36 mile through some back roads no problems not topping it out in 5th gear just on off acceleration
Today i took it off road down by the shore where i used to take my xr400 just a bit fun. After about an hour of light ish abuse (i aint no king of the off road) stopped for about 5/10 min then kicked it it over and idled for about 30 secs to put my lid back on and it cut out, no bother fired it back up and away i went. But after about another 15 min i stopped to talk to my mate for 10min. Then i tried to kick it over and it wouldn't so i tried the starter no chance of that so i bumped it down a hill first time fired up straight away then went about 6 mile to another location and took it off road for about 10 min then it stalled when i got to a slow bit and there were no hills to start it. After about 20mins of rage     i pushed it to the road and bumped it.
After that i took it home thinking will this stall at a junction which it never pos due to the fact i kept it revving slightly when i was going to stop.
So any ideas?????????

Also I can't seem to find the ASI removal kit here in the UK anyone know where i would get one thanks

You using the hot start lever?  Is it adjusted properly?  Had this exact problem on my '05 and tracked to the lever cable being way too loose...

Hope this helps

Yup, don't forget to use the hot start.

AKmud, on 29 July 2012 - 09:36 PM, said:

+3  

this bike needs that hot start lever pulled in.  Do not turn the throttle when you try to start it.

However, we are assuming that your jetting is correct.  Is it?

You just got the bike and its an 05.   How is the top end?   A correctly jetted wr with a good top end starts so easily that guys on other bikes would be jealous.

Edited by mauricedorris, 30 July 2012 - 07:44 AM.

Initially I was having hot start problems too... Caused by 2-stroke habits... Keep your right hand off the throttle;)

Jrbuete, on 30 July 2012 - 05:10 PM, said:

It's funny how hard that habit is to break, sometimes I have to
take my hand completly of the throttle because its such a reflex
to twist while kicking. Damn 2-stroke habits !

And I'm currently just the opposite! I've been on fourstroke Yamaha's since '98, and when I tried to fire up my YZ144, I kicked and kicked and kicked some more. Then I remembered to twist the throttle as I kicked, and it fired right up!! Damn Fourstroke habits!!!
Maniac

Jrbuete, on 30 July 2012 - 05:10 PM, said:

Opposite of mine . Half the time when I stall it needs a throttle of gas to start back up... Not sure why but it's been like that since I got it. If I press the starter it just tries to start till I giver some gas

Thanks for the replies. Turns out my hot start leaver was broken behind the rubber boot so i pull it with some pliers and it was jammed. So I've unscrewed the black sort of 90 degree pipe next to the carb choke and filled it with wd40 and wd the cable at the handles no joy. Ive removed the carb and found that the small lug things that hold the cable are seized solid. I got the cable off it and now one has broke off   is there anyway i can replace the part? Ive looked at some diagrams and I think its the plunger starter? can i just drill the old one out? don't want to destroy my baby

Soak in PB blaster for a few days. you may have to use a small slide hammer to pop it out. If you are uncomfortable doing this, take it to a machine shop. Be sure to bring the replacement part so they know exactly what they are dealing with.

Thanks dude ill give it ago tomorrow after its soaked for like 30h. Ive got the new parts ordered so fingers crossed

still2smokin, on 30 July 2012 - 05:42 PM, said:

Those habits are so troublesome that Yamaha saw fit to add a bit about it in the WR450 manual:




Habits are hard to break, and I had the kickstarter broken off of one of my WR450s by a long time two-stroke rider who wouldn't follow the four-stroke starting drill...

He kept opening the throttle despite repeated instructions not to and sure enough eventually it kicked back and there went the kickstart shaft.

If you need to give it gas to start when hot, what would that be?

When using my hot start I occasionally have to crack the throttle a bit to give it a little encouragement. Fires right up though.

AKmud, on 01 August 2012 - 05:30 AM, said:

same thing as me but MOST of the time it needs throttle then fires first hit. Without the extra gas it just tries to start