Project My '90 FZR250 3LN3

I found one on ebay about 5 week's ago, new old stock in victoria, guy was asking about $30 from memory.
Got a bit side tracked looking at other stuff, then when i went back to click on buy it now it was gone.

 

Any FZR owner's had a problem with a slight bogging taking off ?
It seem's to bog a bit from 3000rpm to 4000rpm until it hit's about 5500rpm-6000 rpm then is all good from there up to wot.
I pulled the bowl's off the carby tonight and raised the float's from 16mm up to 17.5mm, also backed off the mixture screw's 1/2 a turn on each carb
It is now feeling a little better but still not quite 100%

Might make a video of the issue too?

 

I picked up a Ventura Light Guard from a local bike shop the other day, marked down in a clearance sale from $40 to $5
It stick's to the headlight with some tiny velcro dot's
Also bought a nos Takasago Excel 12" x 1.6" rear rim for my 190cc pit bike for $30, marked down from $178
Yesterday i laced it up to a new CNC hub and trued it.

 

Haven't been out on the FZR for a couple of week's due to having the XT.
I picked up Morgan Carbtune Pro with pouch for $50 off gumtree last week and decided to give the FZR a check over and see how close i got the carby sync .
The difference was only about 2" Hg across all 4 carb's, number 2 carb was 1 higher and number 4 carb was 1 lower, so my sync with the home made liquid manometer was very close.
I checked the exhaust temp's too while i was at it and had to adjust 2 carb's as well to get them all close
Just as i was finishing up this afternoon the skies opened up and i had to park the bike back under cover, so hopefully if tomorrow is fine i can get it back together and try it out

 

No syncing is getting all 4x carby vacuum level's the same, so they all draw the same amount of fuel/air

 

The FZR idle is pretty smooth now, before syncing it was a bit choppy.
Throttle response is a bit better now, and it should also make the fuel economy a little better
I will need to do it again when i get around to doing the valve clearance's

 

Found a set of vacuum blanking plug's today, so off with the tank again and fitted the new extended vacuum tube's
Even had to make a custom extra deep 1/4" drive socket to do them up

 

I replaced the l/h radiator hose today, old one was slightly swollen, flushed the cooling system, and refilled it with demineralised water and coolant.
I used some 19mm heater hose, it stretched over the 22mm waterpump barb easily enough and compressed onto the 17mm radiator tube
I was wondering what people have used here other than the genuine hose ?
I was thinking this Mackay Falcon heater hose CH1300 (15/22 x 1030) or the CH1672 (15/22X x 730) might work as well if i had any problem's?
http://www.ebay.com.au/itm/Mackay-H...877726?hash=item2ca56bf8de:g:iuMAAOSwZJBYALKm

 

As mentioned in another thread i finally got around to doing the valve clearance's in the FZR, they were pretty tight
Think i need to find another head next so i can rebuild it and swap it over at a later stage

With the new shim's and clearance's done i started up the bike and had my Carbtune sync tool hooked up.
You can see the difference the clearance's have made as there is hardly any flutter in the sync tool rod's now.
Surprisingly the sync hadn't changed, but i'll give it a bit of a tune on the mixture screw's today anyway

I cleaned up the rocker cover bolt's and repainted them and the washer's and fitted the spare rocker cover that i blasted and painted age's ago, the cover look's a lot better than in the standard Magnesium finish
And i noticed my rocker cover gasket has some crack's in the half moon's at the end so will order another one soon (Zeal gasket)

And i cleaned up the COP coil's, and wrapped them in some red vinyl that i had left over from the XT250 to make them look better too

 

Took the FZR250 for a ride today out north to check out a new engine for my wife's Mazda 3
There was lot's of traffic and roadwork's, took me an hour and a half to do 60km's on the way up, but only took 45min's to get home going another way.
The engine goes pretty good, i still think it's a little rich so will have to check that out again
I've tried the float's at 17.5mm but had a flat spot around 4000rpm- 4500rpm,
then set them to 16.5mm and flat spot is at 4000rpm, and now have them at 16mm and it still has a slight hesitation around 3500 rpm
Best mixture screw setting is around 3 to 3.25 turn's out, carb sync is very close to spot on

 

I think when i get a chance next i am going to raise the float's a little more to 15mm and see if that help's
I'm using part of a Foodland 4L Iceream container lid for the home made float height tool
And found that i can check the float level by holding the gauge against the float mount, while holding it in my hand




Atm there's a definite fuel smell with the bike idling, and i think with the float height still a touch low i am trying to compensate for it with the mixture screw's
It's a bit hard to see the fuel level with the carb's on the bike so i may take them off and reset the float height's and check fuel level with it sitting on a the bench on a wedge to simulate the carb position when fitted

But i also noticed after the 120 km ride the other day, the fuel level in the tank has hardly dropped

 

I cant see what the fuel level's are at because i cant get my head down between the frame and carby's to be able to eye it properly
They look ok (about 9.5mm) when looking at them from a 45 degree angle (just above the frame), but don't know for sure

Yeah they are too rich,
but with the mixture screw's screwed back in a little(1/8 turn to 1/4 turn) the hesitation come's back and is worse