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Hello,
I have a 2005 crf450R and it is quite difficult to start on the first start-up of the day. It can take up to 20 throttle twists and 20 kicks. Bike runs great and starts very easy once I get past the initial start up( on 1st or 2nd kick).
13.5 piston, stroker crank, hot cam stage 1, steel valves.
I always check and have the valve lash set correctly.
Any ideas??
Thanks, Titan

Welcome to the site !!

Has the bike been sitting ?? , and did this just start doing this , or has it been a ongoing issue ???

What is your current jetting and fuel screw set at , and your elevation ??

Have you verified that the squirt from the Accelerator Pump is just missing the slide and not hitting it ??

Are you using Premium Non Ethanol ?? , and is it FRESH ??

When it does run , does it stall easily ?? , does the Idle fluctuate ?? , and/or does it backfire when letting off the gas , or blubber/bog when giving it gas at any time while riding , and not when on the stand ??

Non Fuel Related:
Have you done any tests on the Ignition , coil, , etc. ??

How does the spark plug look ?? (color)

It could be a number of things , but with little background info aside from what you mentioned , we need to eliminate things to narrow it down ....

It has been like this for a few years, I dont remember when it started.
I use non-ethanol gas, usually only a few weeks old.
I dont remember the carb setting, I will get back on that.
I have not verrified acc pump squirt

It dont stall easily
Idle stays constant
It does bog a bit at first, when accelerating hard from a low rpm
I dont remember any backfiring
I have not checked any electronics
PLug is light tan

Thanks for the interest!!!

Yea , report back with carb specs and elevation , we can go from there .... AP squirt as well

Also try this , disconnect the TPS on the carb (triangle 3 wire plug at top) and see if it starts any different .....

I checked the compression today, air filter and exhaust were on the bike.
1st kick 60 psi
2nd kick 80 psi
4th kick 95 psi
6-7 kicks 108 psi

The factory manual says the compression should be 78psi at 600 rpm. I dont know how this relates to my compression numbers, as I dont know the rpm, I am just using the kick starter??

When you say hard to start do you mean hard to kick over or just takes a lot to start.
If decompression not adjusted properly, you are kicking slightly slower due to high compression it may not be fast enough to fire.

When I say "hard to start", I am referring that it takes many kicks.

The compression numbers you have appear to be in order. I suspect that you just have pilot jetting that needs to be dialed in.
I also would do a inspection for air leaks, hot start cable into the carb.
Several things can effect starting - Temperature changes effect starting, air filter condition, decompression adjustment, fuel quality, ect...

The accelerator pump diaphragm was totally rotted and falling apart! This also explains the slight hesitation/bog too.
Thanks!!!

Hope you got all those little rotten pieces out and they didn't go down any orifices.

I cleaned the carb, and made sure all jets are flowing freely. I installed the "updated accelerator pump assembly" from CRFS ONLY, and I am not sure what the "gap" should be? I am referring to the adjusting screw, that adjusts the pump stroke.
Thanks for all the help!

I was wondering if anyone ever had the ignition coil or wire fail, do they need to be changed regularly???
Thanks for all the help!!

Anything can fail from time to time. In forty years of riding I never had a coil fail but had to replace the wire to the spark plug plenty of times.
Not a problem on old stuff but newer coils and plug leads are epoxied together.

Sometimes it is just a boot failure and replacing that has fixed the problem for me too.
The wire to the plug definitely has a life just like in a car.
No real service interval just check for splits and cracks in the insulation.

Have you no output from the coil?
You can test the coil for correct resistance of the windings.