[sam]

Hello All,
Have a 08 450R which has been incredibly hard to start when cold.

So while attempting to troubleshoot the cold start issue and trying all sorts of fuel screw positions and pre-start routine combinations, I found that pulling the hot start lever with the choke on produced the quickest cold start. Takes just a couple kicks and it fires up.

I don't want to look a gift horse in the mouth, very happy that it starts with this odd procedure but I want to understand what's going on and need help! Why would the contradicting hot start lever (lean) with choke on (rich), help with a cold start? Any ideas?

choke off = no start
choke off w/hot start lever = no start
choke on = no start
choke on w/hot start lever = STARTS!!!

Once the bike is warmed up, it fires up first kick without exception and runs amazing, no backfiring, no bog.

Valve's are within tolerances
JD Jet Kit installed per instructions
Pro-Circuit T4 Slip On
Everything else on the bike is stock

Thank you in advance,
Sam

[euromike_85]

the procedure you are using "should" cancel each other out, as if you were starting without the choke nor the hot start pulled, my guess would be that one of these circuits (hot start or choke) is not operating well, check hot start for smooth operation and full return.

[124]

In the process of over-riding the choke function with the hot start, you may be finding that sweet spot not obtainable with the fuel screw alone.

Meaning that the pilot jet is slightly too small for cold start condition rendering your fuel screw adjustment inadequate.

What pilot jet is in there?
Might want to test one size up.