CBR250 Forums banner

Correct Mixture Screw Settings

5152 Views 6 Replies 4 Participants Last post by  Matt
Hey guys,

I haven't happened to find where my mixture screws are, so was just wondering where they are and what are the optimal settings (if there is a way to measure)..

My bike doesn't like starting all that much when it's cold, even after I've cleaned the carbies. (It usually starts on the 3rd or 4th try, which isn't that bad.. but I'd still like to make sure the correct oil/petrol mix is being used)

My idle is at about 2k RPM and I've seen on these forums that it should be around 1400-1600 so I'm going to turn that down a bit.. but a little bit too much petrol shouldn't be stopping it from starting, should it?.. After all that's what the choke does, right? (choke = more petrol, less air?)

It blows a bit of white smoke when first started as well, so maybe too much oil?

1 - 7 of 7 Posts
Oil/petrol mix???

It's a 4 stroke buddy.. assuming this is a cbr250?
wait. you said you've cleaned the carbies.

if you haven't found the mixture screws, you haven't cleaned them properly.
Good to see the new thread button still works :p
I just hope you contribute as much as you ask.

Anyway someone will be able to post a pic of the screws. I'm no expert but I have found the mixture to be trial and error. But its not rocket science.
just above the black rubber boots are some bronze screws.

where it says pilot screw here

turn them in firmly, but not too far. just til they the bottom. then turn them out to the factory settings. (1 1/2 or something)
See less See more
dayeve said:
Good to see the new thread button still works :p
I just hope you contribute as much as you ask.
Well I've had my bike for 3-4 weeks so I'm not exactly an expert just yet. I'm asking questions so I can learn. Once I know all the answers and have experience doing all the general things, I can then give advice to people new to bikes..

No use giving advice if I don't know what I'm talking about..
i would argue that there is no use in working on the bike if you don't know what you are doing. you can inadvertently damage stuff.
1 - 7 of 7 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.