FZR400 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
IanG1
Settled in member
Reactions:
Posts: 13
Joined: Tue Jun 03, 2008 11:56 am
FZR400 1WG running problems

Post by IanG1 » Wed Jun 04, 2008 8:04 am

Hello all,

New around here but I will cut straight to the chase and pick your collective brains.
I have a 1WG pre EXUP 400 that I picked up cheap as a trackday project. It has a few running problems that I need some ideas on.
It starts up from cold straight away on choke and ticks over nicely, as I decrease the amount of choke it seems as if the right hand outer pot isn't firing properly( exhaust pipe cooler that the others, though hot when on choke) I thought the pilot jet may be blocked so dropped the carbs off, to be honest they looked quite clean inside but I blew out all the jets anyway, put it all back and still the same. I have also swapped the plugs over to no avail?
It also seems reluctant to rev above around 7/8K and coughs and farts a bit.
With it running on choke, I guess the problem must be carbs, is this a common problem, anybody offer any ideas
I bike has been stood for a while so maybe some of the internal passages are gummed up?

Ta in advance

Ian

Taggyd
Site Supporter
Site Supporter
Reactions:
Posts: 1015
Joined: Thu May 15, 2008 2:03 pm
Bike owned: fzr 400 3tj x 2, cbr900rrs
Location: Ironbridge, uk
Re: FZR400 1WG running problems

Post by Taggyd » Wed Jun 04, 2008 11:07 am

clean the fuel filter? Drain the fuel and put new in to start with, have you checked the coils as if its only one cylinder maybe there is a problem with that? Also you could take off and clean the pipe into the carb in question incase it has got a load of crap in from standing. What is the inside of the tank like?

IanG1
Settled in member
Reactions:
Posts: 13
Joined: Tue Jun 03, 2008 11:56 am
Re: FZR400 1WG running problems

Post by IanG1 » Wed Jun 04, 2008 12:47 pm

I thought 1 coil did the outers and the other the inner 2 cylinders so surely a pair would be running rough, suppose it could be a lead but why would it fire on choke? Tank is clean, will change the fuel though as I am not sure how old it is?
Are any of the carbs interchangeable on the rail so I could swap them over and try and pinpoint the fault.
Anyone got any good methods of cleaning out carbs internal passages etc?

IanG1
Settled in member
Reactions:
Posts: 13
Joined: Tue Jun 03, 2008 11:56 am
Re: FZR400 1WG running problems

Post by IanG1 » Wed Jun 04, 2008 6:53 pm

Well spent the afternoon tinkering about, stripped down the carbs again, reset the pilot air screws, drained and re-filled with fresh petrol and she seems loads better. carbs could do with a balance I think but she now sounds sweeter. She also reved to 12K :mrgreen: so things on the up. just got to sort a few other jobs (someones put new pads in calipers with sticking pistons :o ) change the oil and coolant and put on some new tyres and she will be ready for the track :D

Evilchicken0
Site Supporter
Site Supporter
Reactions:
Posts: 9490
Joined: Tue Apr 29, 2008 8:59 pm
Bike owned: Bimota SB6 Yamaha FZR 3TJ x2
Location: Lundin Taan
Re: FZR400 1WG running problems

Post by Evilchicken0 » Wed Jun 04, 2008 11:26 pm

Sounds cool.
Check the airbox rubbers haven't got hard as the airbox will be difficult to get on. Your right about the coils. Renew the fuel filter as it's cheap and is a service item. Just put a bit of carb cleaner through the fuel pipe but it sounds ok. I usually run a little carb cleaner fuel addative in the tank for a couple of fill ups

Taggyd
Site Supporter
Site Supporter
Reactions:
Posts: 1015
Joined: Thu May 15, 2008 2:03 pm
Bike owned: fzr 400 3tj x 2, cbr900rrs
Location: Ironbridge, uk
Re: FZR400 1WG running problems

Post by Taggyd » Thu Jun 05, 2008 10:13 am

if you're racing you ccould get a more free flowing filter to help flow.

torpytanktop
Settled in member
Reactions:
Posts: 10
Joined: Sat May 24, 2008 8:00 am
Re: FZR400 1WG running problems

Post by torpytanktop » Sat Jun 07, 2008 10:23 pm

I'm just in the process of cleaning my carbs. The pilot screws are 3 turns out - is this correct? Can't find the info in the service manual....
Thanks.

User avatar
Motorcycle Solutions
Site Supporter
Site Supporter
Reactions:
Posts: 248
Joined: Wed Apr 30, 2008 9:05 pm
Bike owned: Kawasaki ZX9R E1
Location: Warwickshire
Contact:
Re: FZR400 1WG running problems

Post by Motorcycle Solutions » Sat Jun 07, 2008 11:02 pm

I always set mine between 2 1/2 to 3 1/2 turns, so you are not too far out :D

IanG1
Settled in member
Reactions:
Posts: 13
Joined: Tue Jun 03, 2008 11:56 am
Re: FZR400 1WG running problems

Post by IanG1 » Sun Jun 08, 2008 9:12 am

torpytanktop wrote:I'm just in the process of cleaning my carbs. The pilot screws are 3 turns out - is this correct? Can't find the info in the service manual....
Thanks.
The manual I downloaded said 3 and a half, so thats what I set mine too


Post Reply