Close to getting the matches out...running issues 3tj

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
User avatar
pauliealdridge69
Site Supporter
Site Supporter
Reactions:
Posts: 1429
Joined: Sun Oct 17, 2010 5:47 pm
Bike owned: Nc30,35,998s
Location: Oxfordshire
Contact:
Close to getting the matches out...running issues 3tj

Post by pauliealdridge69 » Sat Jul 15, 2017 3:27 pm

Bought a "running" fzr400 3tj to do a track day on a few weeks back. That's been and gone already and I'm getting close to giving up on her now (second time I've said that)
Any ideas and advice much appreciated...
Bike starts flick of the key on full choke, touch the throttle it dies.
If you let it warm up a little, slowly turning choke down to half you can get it to rev but won't go past 4K. Sounds like it's hitting a rev limiter.
I stripped and cleaned carbs three times. Same. Needles were in the wrong places, 1-4 were in 2-3. But all the circuits all seem to flow, diagphrams are good.
New coils, leads and plugs. Was getting nasty electric shocks touching leads. Still the same.
Fresh super unleaded
Swapped ignition over to a bdk that came with it. Still the same.
I've changed the carb rubbers over as revs seemed to raise a little on 2. Now all seem sealed. When ticking over it's now not making any changes spraying around them
Got 12 bikes, 9 in bits lol, this was meant to give me a break and some fun whilst putting the others back together after a house move/shed build and an operation last year on my back but has now turned into a f**king nightmare!!
Before being stood the bike was running fine. I bought it from a good friend, so know it was. It's been sat in a dry garage for 18 months, he has removed a few road going bits and taped up the loom but nothing's been cut. Is there anything simple I could of missed?
The miss seems far to precise to be carbs, it does sound like a rev limiter cutting in.
I'm running out of ideas!

User avatar
pauliealdridge69
Site Supporter
Site Supporter
Reactions:
Posts: 1429
Joined: Sun Oct 17, 2010 5:47 pm
Bike owned: Nc30,35,998s
Location: Oxfordshire
Contact:
Re: Close to getting the matches out...running issues 3tj

Post by pauliealdridge69 » Sat Jul 15, 2017 4:25 pm


Alext900
Settled in member
Reactions:
Posts: 57
Joined: Thu Mar 02, 2017 5:32 pm
Re: Close to getting the matches out...running issues 3tj

Post by Alext900 » Sat Jul 15, 2017 7:08 pm

Have you got correct igniter box for the bike, original? Or?


Sent from my iPhone using Tapatalk

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: Close to getting the matches out...running issues 3tj

Post by Evilchicken0 » Sat Jul 15, 2017 8:30 pm

So it starts as runs ok but won't go past 4k ?

User avatar
pauliealdridge69
Site Supporter
Site Supporter
Reactions:
Posts: 1429
Joined: Sun Oct 17, 2010 5:47 pm
Bike owned: Nc30,35,998s
Location: Oxfordshire
Contact:
Re: Close to getting the matches out...running issues 3tj

Post by pauliealdridge69 » Sat Jul 15, 2017 8:46 pm

Starts on full choke instantly
Won't go off choke, as warms you can get choke half off but it stalls as soon as you touch the throttle.
Once warm will start on half choke and some throttle and if you can get it to rev 1/10 times it will only rev to 4K.
Check float heights all good earlier (fuel level check)
I've just had the manifolds off again. Going to seal them with a smear of something.
Was initially sure it was the pilot circuit but carb cleaner blows nicely through all passage ways in carbs
Can only think it's air if carbs are clear

User avatar
pauliealdridge69
Site Supporter
Site Supporter
Reactions:
Posts: 1429
Joined: Sun Oct 17, 2010 5:47 pm
Bike owned: Nc30,35,998s
Location: Oxfordshire
Contact:
Re: Close to getting the matches out...running issues 3tj

Post by pauliealdridge69 » Sat Jul 15, 2017 8:50 pm

Alext900 wrote:Have you got correct igniter box for the bike, original? Or?


Sent from my iPhone using Tapatalk
Running the same on original and bdk box

hunter
Site Supporter
Site Supporter
Reactions:
Posts: 2141
Joined: Thu Nov 20, 2008 1:09 pm
Re: Close to getting the matches out...running issues 3tj

Post by hunter » Sat Jul 15, 2017 9:07 pm

This sounds like a pilot jet issue.Or circuit.

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: Close to getting the matches out...running issues 3tj

Post by Evilchicken0 » Sat Jul 15, 2017 10:05 pm

I don't think the bdk boxes have an adjustable red line. 4k is too low to be the change onto mains.
I'd put new idle jets in it.


Post Reply