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Hot start Wr450

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I just got a 2003 WR450 and the starter wasn't working so after learning how to kick this bike I could start it in one kick. (find tdc, easy piston past, full kick and it would fire.) After installing the new one it does start the bike as it should when cold. Meaning if the motor hasn't been run I can pull the choke and push the button and it fires right up. (quick) Once I take the bike off choke and ride it for awhile if I turn it off it doesn't want to start easy again. I've tested pulling the hotstart while running to lean it out and then kill it. This seems to help an instant off and back on for say less than 30 seconds. If the bike sits it doesn't want to start again and I have to pull the choke for a second and then push in and pull the hot start to clear the rich condition that I just created and then it will start. I've tried a slight pump from the accelerator and then the hot start and while that does work I haven't perfected that for an easy start. When the bad starter was in it was dragging abit and it was easier to find to roll slightly past TDC. Now once past TDC engine rolls past too far to get a good kick. 

Temperature high 80's to low 90's
Elevation 850-1250
Main Jet 165
Slow Jet 50
Starter 65
Fuel Screw 1.25 
Leak jet cant get out so I don't know the number.
Gray wire mod - Tested with and without.
TPS still hooked up

Side note the intake valves are now down to .004 and that's on the tight side and I will be adjusting them this week. I know that this could have something to do with hot starts as valves might be cracked slightly and the over rich and then back to lean with the hot start helps it start.

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Pilot jet is waaaay to big. 45.

You make no mention of the rest of the tuning: intake, exhaust, ACV system operation, needle, hours on motor, last time the carb wear parts were changed, etc.

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Your right it is, bike came with a 175 main and that 50 and my local shop only had a 43 which was too lean so I left the 50 to go ride. Exhaust it's Yamaha but has a stainless can and the header doesnt look small. The AIS has been removed and the snorkel too. I don't know how long the engine as been together. Just got it. Previous owner had it for 2 years and had hurt his back. I haven't taken the carb all the way off the bike yet. Just cleaned the pilot jet and accel pump and bike ran fine. I will see if I can get a 45 before I ride this weekend. 

The pilot jet shouldn't make it hard to start hot though.

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idle mixture waaay too rich. That's why is fires up cold but not hot.
Learn to adjust the idle mixture. However, if some one has put in other jets way off normal values, you might end up with a perfectly starting bike that still runs shitty a say 1/8 throttle.

Get jetting hints from Krannie, eh should know, and then dial in your idle mixture.

Dig out the zillion posts I did with regard to idle setting and electic start in gear, here's the concept in a nutshell:
Find the mixture setting where the bike can idle with the lowest possible idle setting (super close to stalling).
Then turn up idle speed to usable values and enjoy. 
Work for all bikes I ever had, including the 2012 EFI WR450F (but to do that on an EFI bike you need the "electronic mixture screwdriver" (~90USD) )

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The 45 made it easier to start hot for sure. Bike still doesn't like the easy button every time. Seems like battery is going south as it turns over slow or not at all and then sometimes it's fine. Battery tested good but I think I will replace it. Thanks for the help guys.

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