Project My '90 FZR250 3LN3

Yeah that's how i've done it previously on this bike but you cant see how exact it is
With the bike on a paddock stand that raises the rear wheel 45mm off the ground, so the bike is no longer level, i had to put some wood under the front wheel at the same time as the rear on a stand to get the bike back to level again

 

It's a lot easier to set the float level's with the float assembly in your hand, compared to doing it on the carby/bike

Yeah the carb's have had a thorough clean out and i used new full Keyster kit's in them, so it's got all new fuel jet's, air jet's, needle's, emulsion tube's, needle and seat, o ring's and gasket's etc etc, the 4x diaphram's look like they've been replaced, top o'ring's are new, plastic diaphram cover's have been faced, slide's are all good, intake manifold's are all good eg no crack's / no leak's after testing with engine running and spraying them all over with carby cleaner
Tried numerous mixture screw setting's and changing idle speed to check the throttle plate's were as close to closed as possible

 

Yep, so carby's need to come off the bike, be set up at correct angle on the bench with pump connected and then i can check fuel level's

 

I fixed my cracked windscreen today.
I went down to the wrecker's the other day and had a look through their old screen's,
i found one off an old ZXR750 that was about the same size as the FZR, it's made by Panlite and has DOT approved on it, the condition wasn't that good, scratched, scuffed and faded but it was only $20 so i bought it.
Today i rubbed it back and polished it, came up well, next thing was to take the old screen off and sit the ZXR screen up against the fairing and mark it up to cut.
It only needed about 25mm to be trimmed off the bottom edge, and the hole's to be redrilled.
That took a hour or so and i've got it bolted back on ready to go now, hopefully it last's a bit longer than the cheap china screen's that are only 2mm thick, the ZXR750 screen is 3mm thick and has a 6mm thick bead running across the back.

 

I changed the float levels to 15mm this afternoon and just took it for a quick ride.
It seems to be a bit better again, depending on how it goes when i take it for a longer ride tonight i might have to raise the floats to 14mm.
The fuel levels are roughly 9mm-9.5mm now but i cant tell exactly as i left the carbys on the bike.
Mixture screws are at 2.75 turns out.

 

Yep they might be different, i can't remember seeing a fuel height listed for the 3LN3 5 or 6 in the 3LN supplement.

That Zeal thread beano linked above has the fuel height at 10.5mm
Although his pic's show it being 10.5mm below the line ?

I read on another Zeal blog that the service manual had it wrong and it should be 10.5mm.

 

Took the bike out for a longer ride, it's definately going better again
I think the fuel level still need's to come up a little though
I might have another go at it over the weekend

 

i didn't get around to adjusting the float level's over the weekend
But i did take the top tripple clamp off and cleaned it up, i filed back all the casting burr's to give it a smooth finish and then bead blasted it, gave it a coat of black etch primer and then 3 coat's of gloss black
I'm not sure if i'll keep black now, it does seem to make the bike look longer though ?

@Joker do you remember what your float height's are set at or your fuel level's are set at on your 3LN3 ?

 

I've been doing a bit more research on the 3LN3 float/fuel level's.
I found some post's on a Zeal blog saying the float's should be set at 13.7mm, and the mixture screw's at 1.75 turn's out




Also i've been trying to find a decent wiring diagram for the 3LN3, to see if running the COP coil's off an extra relay will help at all.
It look's like the coil's run directly off the fuse box, powered when the ignition switch is turned on.
I found this wiring diagram for the FZX250 Zeal, and i guess the FZR250 would be very close

 

No, from what i have read it seem's there is a voltage and current drop to the COP coil's when using the standard wiring from the TCI
This can cause the COP's to run at 85%, but apparently they still put out more power than the original coil's.
My FZR has a .3v drop between the battery and coil's, i'm trying to work out if a relay and new wire's to the positive side of the coil's will solve this