HELP - 1990 Suzuki Bandit 250 won't start

[NZAlexander]

Hey guys, I am a university student with a basic knowledge of bike mechanics and have a 1990 bandit 250 that has been sitting unused for about 2-3months.

My problem is it wont start. I have done basic tests like check the plugs are sparking and started is turning etc and its all good so I think my problem might be moisture in the carbs?

Does this make sense? Should I unscrew the carb drain screws and let all the fuel out?
Any help is appreciated

Cheers

[haydes55]

Is it turning over at all? First port of call is check the battery is still charged.

Cold weather and sitting for a while can fuck with batteries.

After that, drain the carbs, Chuck some fresh gas in it and give it a crank.

[spanner spinner]

the fuel will be stuffed, modern fuel doesn't store well and the 250 fours are really picky about fuel quality. Drain ALL!!! the fuel, tank and carbs, and put some fresh fuel in it and when you try to start it connect up a jumper battery in parallel so it turns over quickly this will usually fire them into life.

[NZAlexander]

I had a crack at giving that a go but the nuts (allen key heads) are done up really tight on the carbs drainage holes.
Scared of stripping the heads any advice on how to loosen them?

All i can think of is Crc and hit with a hammer to try and shock them into turning.

EDIT: Yes the bike is turning over when i try and start

[haydes55]

You mightn't need to take the entire bowl off the carb. Is there a drain plug on the bowl? Some carbs have a big bolt in the middle to let it drain out. Pics help.

Buy a can of penetrating oil or similar, that'll help dislodge a stubborn bolt. Or try heat. A hot air gun can help free it up... But you're dealing with fuel. Don't be stupid and get it too hot, don't sit close sniffing it... Basically don't be stupid.

[neels]

My son had a GSXR250 that was the same, if left sitting didn't want to start.

All we used to do to it was stick the jumper leads on it from a big battery and keep turning it over until it eventually fired into life, choke made it worse, had to try and fire before using the choke otherwise it would flood itself.

[haydes55]

Any fix would probably be a bandaid to the real problem. Full carb rebuild would mean it will start again in 6 months time.

[NZAlexander]

I have found 4 little bolts underneath the carbs and undone 3/4, this has drained all the fuel out of the bottom.
CAnt get the third one to undo and im scared of stripping the bolt.

Will this be enough to put some more fuel in the tank and try starting it up?

[haydes55]

I have found 4 little bolts underneath the carbs and undone 3/4, this has drained all the fuel out of the bottom.
CAnt get the third one to undo and im scared of stripping the bolt.

Will this be enough to put some more fuel in the tank and try starting it up?

Stale fuel would still be in the bowl, do that and flush it through with fresh fuel will work good enough. Or just do it all up and start cranking it through.

[hayd3n]

if it still wont start after fresh fuel you may need to replace/ clean your spark plugs , i had to do this last week as my bikes been sitting over winter,

[neels]

If it is stale fuel that's the problem, what you've done will be enough to get 3 out of 4 going, and that should suck enough fresh fuel through the last one for it to go eventually.

Don't forget to set the fuel tap to prime when you try to start it, as there isn't enough engine vacuum when cranking to get the fuel through to start it before the battery goes flat.

[NZAlexander]

If it is stale fuel that's the problem, what you've done will be enough to get 3 out of 4 going, and that should suck enough fresh fuel through the last one for it to go eventually.

Don't forget to set the fuel tap to prime when you try to start it, as there isn't enough engine vacuum when cranking to get the fuel through to start it before the battery goes flat.

What is prime on the fuel tap?

I have On, Res, and something at the bottom that i cant read.

I will assume this is prime? as when was draining it and it was set on this the fuel kept flowing through.

I tried cranking it over a couple of times today while connected to my car battery to give it an extra kick.

Two problems were: the fuel switch was set to on, and i think there wasn't enough gas in the tank.
Ill get organised to buy a tank and go to the gas station tomorrow and fill her up to try again.

Thanks for the help guys appreciate it.

[Big Dog]

Prime usually allows fuel to run through without vacuum. My old Yamaha needed that to start after a long weekend.

My wife's 250 is a Bastard to start if it sits. Shaking her side to side seems to get it to start but it still rubs rough till new fuel goes in.

Sent via tapatalk.

[NZAlexander]

Got it working guys thanks for all the help!

Just hooked it up to car battery after draining carbs and new fuel in the tank. Put it on prime and had it going in 5 mins.

[hayd3n]

Got it working guys thanks for all the help!

Just hooked it up to car battery after draining carbs and new fuel in the tank. Put it on prime and had it going in 5 mins.

sweet now go for a hoon