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Sauerkraut
16th March 2010, 19:13
Hi guys,

I have a '92 Bandit 250 that I picked up a month or two ago. It has been absolutely brilliant since I bought it, always started first time and never any trouble. Over the last few days though it got a little more reluctant to get going 'til one morning I finally got it started and it was really struggling (idling at less than 1,000rpm) and then it just died. Battery was flat so I recharged it but now it still does not start at all.

So I've taken it to bits and so far:
Got spark
Got fuel
Battery's sweet
Starter is working fine

I haven't looked at the carbs because I don't know what to do with them. When I hold the starter down the bike will fire once or twice but not catch, and sometimes it sorta backfires (exhaust goes PAF and spits out a little puff of smoke).

Can anybody help me at all? I've reached the end of tenuous mechanical knowledge and it's really frustrating because the bike has never been difficult before. Something I'm missing?

Cheers!
98tls
16th March 2010, 19:22
When you try and start it can you smell fuel?as in its flooding.
Sauerkraut
16th March 2010, 19:28
Not as far as I can tell. No fuel smell plus I had drained the carb and had a squizz down into the engine when I pulled the sparks out. My dad reckons the backfiring might be a timing issue, which makes me nervous 'cause I don't actually even know what controls the timing on my bike.
98tls
16th March 2010, 19:39
Re timing,it was going fine then it wasnt,timing just doesnt go bad for no reason,Its either fuel or spark,possibly a sticking float,bad spark lead etc.Fwiw try starting it with the throttle wide open,if away it goes then its flooding.To be honest its hard to pin point over the web i guess.Have you got any spare plugs to try?
Sauerkraut
16th March 2010, 19:49
No spare plugs but the ones I've got look like they're almost ready to be replaced anyway, so I'm gonna go get some more. The ones that were in there were all mismatched anyway. I'll try with the throttle wide open.
How tough is a sticking float to sort out?
Sauerkraut
16th March 2010, 19:54
Just remembered as well that the bike had been running a little rough for a day or two before it stopped alltogether - difficulty in starting but accelerating very unevenly at times as well. If that helps diagnose at all!
Hopeful Bastard
16th March 2010, 19:55
Re timing,it was going fine then it wasnt,timing just doesnt go bad for no reason,Its either fuel or spark,possibly a sticking float,bad spark lead etc.Fwiw try starting it with the throttle wide open,if away it goes then its flooding.To be honest its hard to pin point over the web i guess.Have you got any spare plugs to try?

How would you fix this Flooding issue?
CookMySock
16th March 2010, 19:55
Full choke, try and start it normally.. spin it for 3-5 seconds, then stop. Smell the exhaust - any fuel smell?

If not, look under the carbs and find the drain screw and open it, and see if any fuel comes out. If not, check there is actually fuel in it. Pull the fuel hose off the tank and turn the tap on and see if fuel flows out freely.

Pull the tank off and find the fuel pump - the fuel line from the tank should go to it. It is probably operated by a vacuum line from one of the carbs, so pull this line off the carb end and also pull the fuel line from the pump going to the carbs, and suck on the vacuum line with your mouth - this should operate the fuel pump and squirt fuel out - if not, the fuel pump is stuffed.

Usually stuff like this is something simple, so dont panic and start thinking bad engine thoughts.

Steve
kevfromcoro
16th March 2010, 20:05
Hmmm interesting.. could be a number of things.
The bike was running rough a couple of days before hand..
It hasnt sucked a peice of the aircleaner into one of the intakes has it..?
Just a thought..............
Logpot
16th March 2010, 20:06
After reading many similar posts about bikes not starting or running rough the most likely causes are either bad fuel, a fuel blockage, bad spark or combination of all 3
sinfull
16th March 2010, 20:15
After reading many similar posts about bikes not starting or running rough the most likely causes are either bad fuel, a fuel blockage, bad spark or combination of all 3

I'd go with bad fuel/water in the tank ! Unless the air filter is that gunked up its finally said enough !
98tls
16th March 2010, 20:15
How would you fix this Flooding issue?

At this stage we dont know if it is flooding but if it turned out it was i would first look at a sticking float.
Hopeful Bastard
16th March 2010, 20:19
At this stage we dont know if it is flooding but if it turned out it was i would first look at a sticking float.

Ok. Sounds good.. Mine wont start with the choke on.. But it does start with a half open throttle.. Also had a nice backfire the other day.. Made me jump 6ft into the air! Seeing as i aint up on all the mecanicsm and aint no where a mechanic.. Is this a task that is easily do-able?
Sauerkraut
16th March 2010, 20:20
Air filter is OK. I suspected water in my fuel but I drained it out and let it sit for a while and there was no water in it.
Spark plugs and leads are OK and are sparking, just tested them.

When I try to start the bike I can't smell any fuel at all. So I'm starting to think it may be fuel supply problem. I'll try the fuel pump thing that DangerousBastard recommended!
98tls
16th March 2010, 20:23
Air filter is OK. I suspected water in my fuel but I drained it out and let it sit for a while and there was no water in it.
Spark plugs and leads are OK and are sparking, just tested them.

When I try to start the bike I can't smell any fuel at all. So I'm starting to think it may be fuel supply problem. I'll try the fuel pump thing that DangerousBastard recommended!

When you checked the plug was it wet?
98tls
16th March 2010, 20:25
Ok. Sounds good.. Mine wont start with the choke on.. But it does start with a half open throttle.. Also had a nice backfire the other day.. Made me jump 6ft into the air! Seeing as i aint up on all the mecanicsm and aint no where a mechanic.. Is this a task that is easily do-able?

Yep,take the bowl of the carb and check that the float moves freely,as simple as it sounds.
Logpot
16th March 2010, 20:26
Have a read of this: http://www.kiwibiker.co.nz/forums/showthread.php/111708-1996-bandit-250-bogs-down.

It's not the same exact problem but do any of these symptoms sound familiar?

A call to the Motorcycle Doctors might be on the cards if you can't get it sorted yourself as they helped with this Bandit's carb problem.
CookMySock
16th March 2010, 20:47
When I try to start the bike I can't smell any fuel at all. So I'm starting to think it may be fuel supply problem.You should be able to suck a tight vacuum on the vacuum line to the fuel pump. Suck on the tube and then block it with the tip of your tongue and it should hold the vacuum. Watch out, coz if the diaphragm is holed you might end up with a mouthful of petrol. Suck repeatedly and it should pump a teaspoon of petrol out at a time. Examine the hoses in the area for leaks or cracks.

Steve
Hopeful Bastard
16th March 2010, 20:48
Yep,take the bowl of the carb and check that the float moves freely,as simple as it sounds.

Hrmm.. Might have to do that.. Hey.. Gives me something to do while the bike isnt registered eh??

Time to search on utube for taking a bowl off the carb. Yup. i do not know anything, And im not afraid to admit it :) All i know is to oil me chain, check the bike before a ride, fill 'er up with gas and which is the go faster switch! :)
GOONR
16th March 2010, 20:50
Have a read of this: http://www.kiwibiker.co.nz/forums/showthread.php/111708-1996-bandit-250-bogs-down.

It's not the same exact problem but do any of these symptoms sound familiar?

A call to the Motorcycle Doctors might be on the cards if you can't get it sorted yourself as they helped with this Bandit's carb problem.

That do be my bandit in that thread.. It's a real common issue with them, carbs fuck out easy as. George from Motorcycle Doctors is a real good fella. If ya can't sort the bike out yourself give him a yell.
Sauerkraut
29th March 2010, 22:40
Bike got going again! Just swapped out the plugs for some hotter ones and cleaned the fuck out of the carbs. Got George to give the bike a service and go over the carbs anyway, he rebalanced them and replaced a few bits that were far gone. Bike runs like a dream now.

On a completely unrelated note, where can i get an air filter for a 250 Bandit? Colemans want close to 80 bucks for a new one which seems really steep to me. Any recommendations?
Hopeful Bastard
29th March 2010, 23:08
Bike got going again! Just swapped out the plugs for some hotter ones and cleaned the fuck out of the carbs. Got George to give the bike a service and go over the carbs anyway, he rebalanced them and replaced a few bits that were far gone. Bike runs like a dream now.

On a completely unrelated note, where can i get an air filter for a 250 Bandit? Colemans want close to 80 bucks for a new one which seems really steep to me. Any recommendations?

Ebay. Can find almost anything on there.. lol