06 450X Hard to start

I just picked up a 06 450x and am having issues getting it to start. The bike was setup right from what I could tell. ProCircuit Exhaust, air box mods, R cam, jetting (supposedly), etc. I have yet to check the jetting, but it runs great when it is running. I was amazed that she did 97mph down Morelia Rd, and 107 mph (strong tailwind) down MX3. 14/47 gearing. She kept up with a 650R (15/47 gearing). The first time I rode it, it took a minute to fire up. The second day, I had to pop start it (easy). Once warm, the starter spins fast enough, but it has to spin for awhile to get it lit. The kick starter is about the same. 10-20 kicks. It just barely wants to get going. We messed with the idle screw, up and down with no help. Any ideas? My 650R (stock carb) starts first or second kick in flip flops every time, hot, cold, laid down, whatever. Thanks in advance for any help. Other than this little issue, the bike is great!:thumbsup: Also, any jetting suggestions for Baja? My mileage varied between 78 miles and 108 on 3.2 gal IMS.

I would start with a valve check and go on from there. BTW, welcome the 450X forum!

Valves checked out good. 18 intake, 29 exhaust. Any other ideas. Thanks!

I'm stumped and not enough info. anyway to make any rational suggestions. Might try trouble shooting the hot start and decomp. after looking at the fuel screw and jets.

I checked the plug, and it had a smidge of carbon build up and the gap was a touch tight, so after I gave my local dealer $17, i now have a new correctly gapped plug installed. Still can't get it started. Messed with the idle screw, and can get it to pop back through the pipe every now and again, but still not even close to starting. I can't imagine that it would be the jetting, as the bike runs great (once it is running), and the plug looked ok when it came out. The only thing that I have done to it since I got it was add a IMS tank (which I cleaned out). It fired up fairly easy the first day of riding, and then ever since, issues. Thanks Guys!

You keep mentioning the idle screw: do mean the fuel screw? The idle is not that important yet.

- Fuel screw is under carb, near front: 1.5-2.25 turns out

- While youre down there, loosen the carb clamps, rotate the carb clockwise, and take off the float bowl. If there is ANY crap in there, check the piliot jet. Don't loose the float pin or needle.

Take out the piliot jet and hold it up to the light, and look for clogs. Clean with a single strand of speaker wire (or spray chemicals and compressed air).

- With a new plug, clean jets, and clean gas, and a bike that will tow start, it would have to be valves. No big deal. Two hours the first time. Bring a friend for support.

Just a thought but make sure you are getting gas to the carb.

You mentioned you put a new gas tank on, maybe something is causing not enough fuel to get into the carb. Your jetting/valves could be perfect but if you have no fuel well then...to start an engine you need fuel, air and spark and good compression.

Since the tank, I have put over 275 miles on it. It will pop start, and run but the starter and the kickstarter won't get it lit. It has a boysen quick shot on it, and I'll go into the carb tomorrow.

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