Start-up needs throttle & maintaining idle or engine cuts out?

[Jackpot]

Hi,

I recently purchased my first motorcycle '2007 Honda CBF250' a month ago.

I had some issues with start-up always requiring throttle and maintain idle so I took it to a knowledgable friend who helped me give the carb a check (body(?) was clean so did not investigate further).

All was fine until earlier the bike started to cut out when stopped or the idle came low. Almost like it ran out of fuel. It still has ~50% indicated so it can't be this.

Any thoughts on what I could do. I am a beginner so happy to spend some money to get it looked at but if there is something small I could check then any help would be great. Any estimates on cost would be appreciated too.

Thanks

TL;DR - What is the fix for the start up, idle issues, sudden high rev's?? And, what do you ask for when you want to fix the general running order of a bike so I can commute.

[Rhys]

Have you replaced the fuel filter, also when it stalls try opening the tank to see if the is a vacuum

[Jackpot]

I haven't replaced or looked into the fuel filter and iI'll have a look into the vacuum. Thanks

Edit: Update - the nut at the end seems to be all but rounded... bugger... The connected body is just stuff and doesn't want to twist/turn..

Took it for a ride around the local streets and it stalled in low revs and opened the tank but couldn't only hear dripping. Usually 2 then a pause until the next 2

:(

[mossy1200]

I haven't replaced or looked into the fuel filter and iI'll have a look into the vacuum. Thanks

Edit: Update - the nut at the end seems to be all but rounded... bugger... The connected body is just stuff and doesn't want to twist/turn..

Took it for a ride around the local streets and it stalled in low revs and opened the tank but couldn't only hear dripping. Usually 2 then a pause until the next 2

:(

This seems to be in another language.

Round nuts and dripping?

[Jackpot]

This seems to be in another language.

Round nuts and dripping?

My apologies. I lifted the fuel tank off and could hear dripping inside tank. I am not 100% sure about what to look for in regards to a "vacuum" :( Sorry

By "nut" i mean the area (maybe it is bolt(?)) in the diagram attached of the fuel tap. The workshop manual i have says the filter is in the blue area and can be removed seperatly to the body of the fuel tap.

Cheers. Apologies for the embarrassing use of English...

[ducatilover]

Have the carb cleaned properly and get your valve clearances set.

[mossy1200]

Its most likely blocked jet in carby or the floats are sticking.

Get someone who knows how to clean and set up the carb or take it to bike shop.

If your not sure what your doing stop doing stuff to it.

[Akzle]

carb clean balance, new gapped plugs. Check if youre firing on all cylinders.

[Jackpot]

Any idea(s) on cost to get carbs cleaned and synced then? Cheers

[Akzle]

carb clean balance, new gapped plugs. Check if youre firing on all cylinders.

[Akzle]

Any idea(s) on cost to get carbs cleaned and synced then? Cheers

drain them. Knock them off with a sledge hammer and simmer in a 20lt pot of white vinegar for three days.

[Jackpot]

drain them. Knock them off with a sledge hammer and simmer in a 20lt pot of white vinegar for three days.

As much as I would like to give this a go, learn some things along the way and become knowledgeable about maintaining a motorcycle I may veer on the side of going to a shop this time for personal assurance that it is in 99.99% working order for what it should be before I start fiddling. Plus, the aspects of not using older tools of a relation until I get my own may be better in the long run to prevent further damage.

[The Reibz]

Pull your plugs. Give em a wipe, put them back in. May solve the problem

[ducatilover]

Any idea(s) on cost to get carbs cleaned and synced then? Cheers

It'll only have one carb, no need for a sync at all. I'd do it for $100 at my shop, but I'm too cool to work on a CBF TBH

[pete-blen]

If all ealse fails......

Check that the pilot jet isn't blocked...
Or the tinny holes in emultion tube are clear..
If they are blocked there will not be enough primary vacume at low revs to pick the fuel up
from the float bowl... at low revs the motor has not got enough vacume to suck the fuel up
from the fuel bowl and needs asisstance....