1wg running problems

Forum rules
Please can you post items for sale or wanted in the correct For Sale section. Items / bikes for sale here will be removed without warning. Reasons for this are in the FAQ. Thanks
Post Reply
sells01
Settled in member
Posts: 3
Joined: Tue May 03, 2011 10:22 pm

1wg running problems

Post by sells01 » Tue May 03, 2011 11:03 pm

Hi there i bought my wife an 89 fzr400 1wg but its only running on 3 cylinders. The bike was sat for around 7months without being started before i bought it but ran perfect before apperently. Firstly i changed the plugs but no difference, then i took off the carbs and found the jets were blocked on that carb so cleaned the jets then put it all back together thinking i had cracked it but its still the same (very frustrating). The leads seem ok and i checked the voltage at the cap end and its getting around 18-19volts so spark should be ok. Putting my han ontop of the carbs there seems to be plenty of suction.

Any ideas guys any ideas would be very much appreciated

Also do yous know anywhere i can get a workshop manual.

Cheers

Evilchicken0
Site Supporter
Site Supporter
Posts: 5374
Joined: Tue Apr 29, 2008 8:59 pm
Bike owned: Bimota SB6 Yamaha FZR 3TJ x2
Location: Lundin Taan

Re: 1wg running problems

Post by Evilchicken0 » Tue May 03, 2011 11:20 pm

If you take the plug outand put the HT lead on it, then lay the plug on top of the cylinder head and crank the engine you should be able to see it sparking.

I could be there's still some crap in the carb or the jet still isn't quite clean. For now try lifting the carb slide, squirting a good blast of carb cleaner under there and see if it fires up on 4. If it fires then it's a fuel problem, if doesn't then you might need a compression test.

Welcome to the forum - have a look in the General Section in the top thread there are links to download a manual. You need the SAC Californian model.

Taggyd
Site Supporter
Site Supporter
Posts: 722
Joined: Thu May 15, 2008 2:03 pm
Bike owned: fzr 400 3tj x 2, cbr900rrs
Location: Ironbridge, uk

Re: 1wg running problems

Post by Taggyd » Wed May 04, 2011 9:12 am

check the float heights as well. I had a similar problem and it was because fuel wasnt getting through properly because of the float.

sells01
Settled in member
Posts: 3
Joined: Tue May 03, 2011 10:22 pm

Re: 1wg running problems

Post by sells01 » Wed May 04, 2011 4:28 pm

Cheers guys i will give that a bash and let yous know how i get on.

sells01
Settled in member
Posts: 3
Joined: Tue May 03, 2011 10:22 pm

Re: 1wg running problems

Post by sells01 » Wed May 11, 2011 10:49 pm

Right so sprayed carb cleaner into carbs when bike was running and away cylinder 4 went so i ripped the carbs out again and stripped them down found the filter on the other side of the float valve partially blocked so cleared it, cleaned jets again and blew through all fuel lines etc on carbs, flushed through fuel lines, pump etc. Flushed out fuel tank and put fresh fuel in. Fired her up and away all 4 cylinders went so i thought i had cracked it but............

Took it a little spin out the back road and it wasn't keen on going above 9000rpm's so took it back and when i was giving it a little rev to around 4000rpm the revs were not just dropping straight away they were sitting still for a moment then slowly dropping down. Also if i give it a bigger rev there is a little puff of white-ish smoke comes out exhaust, don't know if that has anything to do with it.

Do yous know what heights the floats should be set at plus any other settings to check out, apparently the carbs were all set up before MOT 9-10 months ago as i spoke to the mechanic that did it so thought they should have been ok??

Again guys any help would be muchly appreciated, getting a bit fustrated now especially after building it all back up thinking i had cracked it.

Cheers
Ian

Evilchicken0
Site Supporter
Site Supporter
Posts: 5374
Joined: Tue Apr 29, 2008 8:59 pm
Bike owned: Bimota SB6 Yamaha FZR 3TJ x2
Location: Lundin Taan

Re: 1wg running problems

Post by Evilchicken0 » Wed May 11, 2011 11:43 pm

Floats don't have a height as such - they need to be done with a manometer or a clear U tube type pipe and then measured against the carb body. Did you check the rubber seals on the valve - it could just be that.
Download a workshop manual and it should have it in there.

Or ask the guy who set them up to check them. Although I'm sure you can do it, it might be easier to throw a bit of dosh at it. At least that way they should be balanced and ready to go and you'll have a bit of a ganentee on it too

Post Reply