CBF500 wont start

[bris]

Just tried to start the 2008 CBF500 for the first time in about 3 months and it wont start. Turns over good but doesn't even try to start. I took the spark plugs out and tested for a spark which was good on both plugs so getting a spark. The fuel is getting out the tank but now I'm stuck any ideas what to check now.

[maviczap]

Gummed up fuel in the carbs, drain it off and fill it with fresh fuel might work, other wise you'll need to strip the carbs down

[bris]

Thanks for the quick reply. Is there an easy way to drain the carbs without stripping everything down.
Found a couple of drain screws so drained of the fuel.

[bris]

Still not trying to start will need to strip the carbs. Is this easy to do and is it easy to clean out. Thanks.

[maviczap]

Get some carb cleaner or clean petrol to disolve to old petrol.

Before you do take carbs off, make sure petrol is getting to carbs, will save a lot of work.

Is there plenty of fuel in the tank, does the fuel get to the carbs, or is the filter blocked?

[andrewsmith]

Gummed up fuel in the carbs, drain it off and fill it with fresh fuel might work, other wise you'll need to strip the carbs down

Mavi im sure the 2008 CBF's are FI
CB's were Carby's

EDIT: I'm a tool, it beat the emission rule changes (that pushed FI as the standard) and is a Carby

[maviczap]

Mavi im sure the 2008 CBF's are FI
CB's were Carby's

EDIT: I'm a tool, it beat the emission rule changes (that pushed FI as the standard) and is a Carby

You had me worried there :stupid:

[bris]

Fuel is getting to the carbs, bit stuck now though as getting the carbs out is next to impossible. Looks like on this bike you need to take quite a bit apart to free them.
Is there no additives out there that will dissolve the gunk.

[maviczap]

Buy some carb cleaner. See suggestions here

http://answers.yahoo.com/question/index?qid=20100216164435AAcaysM

[-Ralph-]

How long have you turned it over on the starter motor for?

[bris]

How long have you turned it over on the starter motor for?
Ages, in fact I had to stop a few times as I didn't want to burn out the starter motor. I had it hooked up to a jump starter so had plenty of power.
It started and ran great a couple of months ago and now with it sitting it can only be the carb problem.
This was something, I must admit I didn't know could happen, you learn something new every day.

[bris]

Final got the carbs off, they look clean or can you just not see any build up of gunk. I have an air compressor, will blowing out all the little holes I see get rid of the crap or should I spray carb cleaner into them. Halfords didn't have any carb cleaner is there anything else I ca use. thanks

[andrewsmith]

Reddex might do the trick if you've got any

[yorkie_chris]

Just air is fine if there's no massive amount of varnish or rust in there.

Careful with carb cleaner as it can attack rubber parts.

[bris]

Back again, the weather held me up a bit. Got the carbs cleaned , although they didn,t look like they were dirty but made sure all the wee jet holes etc were clear anyway. Put it back together again and still the same problem, doesn't even try to start.
I took the plugs out and made sure there was a spark which there was so poured a little petrol in each cylinder befor putting the plugs back in.
When trying to start this time I got a few loud backfires and it did try to start so I think I can rule out elictrical problem, should I try new spark plugs? The backfires worried me a little though so any more ideas out there. Thanks again for trying to help.

[andrewsmith]

For the sake of £15 i would change them.

It sound like a fuel issue, might be the pump is fouled up. Might be worth rigging up a external fuel supply and see if it goes on that

[Dicky Ticker]

I doubt if 13weeks would gunge the carbs up------not trying to be facetious but kill switches,stand,clutch etc---only trying to help before you start stripping everything down

If when you turn the engine over the plugs are wet fuel is getting through