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Hello from Greece.

I have a problem...
I have change my original oem cylinder and piston with this kit:Cylinder Works Big Bore Kit Honda CRF450R 488cc 450R,also the intake valves with steel valves and ofcourse i measure the valve exactly as the manual says,change the clutch kit with this:Honda CRF 450R/450X CRF450R 2002-2009 Clutch Kit Set.

Now when i push the clutch before the entry of a turn or going somewhere slowly with the revs down sometimes the engine stalls and only if a <close> the fuel,kick it 5-6 times <open>the fuel push the hot start,the engine start again.
i d like to say that the compression is really high and when the engine is cold after i kicked it 2 times with the air open the engine runs smoothly.
I have to say that at start i didn t set up the clutch lever correct ,after that the engine stalls again
Please do u thing that is a valve problem or i have to set up the jet and needles from the carburetor and how?
I apologize for my poor English

Skylos-mauros

I don't think it's a valve issue. Sounds like you may have a few things going on. As for stalling in corners, could be jetting or float level. Sound like it's flodding out when you say how you have to re-start it. Jetting can play a factor also. Also, a heavier flywheel could help the stalling issue. You have to remember, these bikes are set up for MX so the flywheels are light for faster revving. In turn, they become prone to stall at lower RPM's. I would try bumping the idle up before you do anything else. Before messing with the clutch, try using a different kind of oil in the transmission. These are just a few things to try before getting any deeper into it. Sometimes the small things help a lot.

Thank u for your reply...i think that u have right..small things make the difference..
I have to admit that this happends only on a special test with time on enduro racing.
So u suggest to add more thin oil on transimission for start?
Also i have to set up right all the small issues on the clutch lever to change the gears on the start of the way of the lever....sorry if i confused u.

I apologize for my poor English

Thanks a lot

Skylos_mauros(dark_dog)

Hello again from Greece.

As i said i have a Cylinder Works Big Bore Kit Honda CRF450R 488cc 450R and i like to know if i have to change something on my carburetor and how or if have to make the AP mode 1?
Do u think that will change anything?

I apologize for my poor English
I look forward for youreply.

cheers
skylos_mauros(dark_dog)

i also have a 450 r they stall out turn your idle up until its seems to high and that will be about right if you still have probs you mite want to go with a slipper clutch but after a big bore install you would need to rejet but only if there is some bog or decel popping ect

i'm not sure i fully understand your issue but you do need to have your idle up higher than you may think. it should not stall just because you are slowly releasing the clutch and at the same time accelerating the throttle. how does the motor idle? is there bogging off idle? how does it perform mid and full throttle?

ken

I apologize if i confused u, and thanks a lot for your reply.
So the idle of my Honda is solid, no up and down,no bogging idle ,everything sound normal.

I will follow the advised to turn the idle up becose i have to admitt that i like to hear my engine <counts> the piston hits.....stupid from side becose i understand from what they said here that the flywheel is very light.

I apologize for my poor English

Cheers
Skylos_mayros(Dark_dog)
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