3LN running Problems

Check the battery and charging system. Least expensive.

 

Definitely a fueling issue.
Cleaning the carbs may help, but it sounds like it could do with a balance aswell.

Let us know how it goes.
Also, wanna put your location in your profile so we know where you are?

 

Taking bets for float heights anyone?

 

mmm, i'm having some fuel issues myself, actually. very similar.

It seems to have sorted itself out now, but yesterday about four times my bike just died and i had to wait for half an hour or so before I could start it again.
When i went turned the ignition on I could hear (what sounded like) the fuel pump struggling. Thought it was the exup playing up at first, but when I wired itt open, the problem was still there.

What's even more frustrating is that I had a major service on friday <!-- s --><img src="{SMILIES_PATH}/icon_sad.gif" alt="" title="Sad" /><!-- s -->

I'm hoping it's just dirty fuel and that the problem won't return (wasn't an issue today).

 

Here we go again...

FZR250's are very prone to flooding... they come here from japan and no one sets them up for AUSTRALIAN conditions... they run a weebit to rich and foul up the Spark plugs!! and ruin the valves...

I was experementing on Komas bike and trying to get the fuel/air mixture set up good and proper but I'm begening to think new jets and needles are in order (his were cactus)...

 

I'll take fuel filter/pump then float heights cause fuel filter is easier to eliminate.

Fuel filter - approx milage you'd get from full bowls would be about 5km when its running at normal load. The fact that it won't start then for a while tells me it is taking time for the fuel to seep through something up the line. Next time take a phillips head screwd driver in the trunk and when it stop jumps off and open one of the carbie drain screws. No fuel = start search behind the carbs up the fuel line starting with the filter. Could also be a seized fuel pump so check for fuel before and after the pump. Could be the fuel tap.

As you are all becoming accustomed to carb problems you may have figured the problems are deeper than settings and in fact related to carb design. Your problem maybe due to the angle the carbs make with the cylinder head. BikeBiz should know about this and had a few bandaids as they had a mechanic a few years ago that spent quite a few hours on the phone with BigLez and I trying to solve uphill/downhill shitty running.

 

Generaly speeking the 3ln does have problems with their carburators.. and what make it very hard is that there is NO information on them.. so people like the mechanic at BikeBiz and otheres have lots of fun time trying to determine the correct settings and correct tuning...

I my self have played around with the 2kr carbes and CBR250 caerbes (at least there is a world of information) so my knowlage is rather general when it comes to the 3ln...

As Starter has sugested check every thing else b4 you start playing with the carby setup...

If there is a problem with the fuel pump I found a ZZR600 fuel pump a good replacement... though Koma is complaining that the bike is running rich when hot...

 

I trust you are revving it enough? A common mistake for people who first ride an fzr is to try and ride it around 6000 revs. Get to 8000 or above when accelerating from standstill - and perhaps when cruising let it settle around 6000.

It could also be problems with the exup valve - a quick, cheap, and easy thing to check and fix (normally). If this is not openning properly you will have too much back pressure and not enough exhaust flow-through to allow for more fuel to burn. Check out <!-- l --><a class="postlink-local" href="http://www.fzr250.com/viewtopic.php?t=676">viewtopic.php?t=676</a><!-- l --> (the link given there to <!-- m --><a class="postlink" href="http://www.cartestsoftware.com/fz1/exupmaintenance.html">http://www.cartestsoftware.com/fz1/exupmaintenance.html</a><!-- m --> may be easier to follow). Often problems with the exup are also associated with running rich - so there may still be some problems in the carbies (despite having these just tuned because there is no guidance on this many mechanics won't know the correct settings for needles/jets or float heights - listen to the people on this board as they have played with this until they found the optimal settings).

Just so you know if anything goes wrong like this on the fzr I have a tendency to say "carbies, exup, or fuel line/filter"... Given the other two have been mentioned it was time to mention exup. <!-- s:lol: --><img src="{SMILIES_PATH}/icon_lol.gif" alt=":lol:" title="Laughing" /><!-- s:lol: -->

 

Anything below 5k rpm is rather weak and not very responsive on all FZR's. If your changing gear low in the rev range it could just be bogging down (ie. lightly flooding). Try and keep your gear changes to around 10k rpm and see if it still splutters.

As for the overheating in traffic - again, common with all FZR's. I wouldn't so much call it overheating, as it's within operating spec until it hits the redline... and unfortunately the thermoswitch will kick the fan in only a tiny bit before it gets to the red.

 

I had some problem on the way home last night ,
after about 5km of riding the bike it had no pick up and splutured.
I got to the 1st streetlight and stopped to inspect. I'v had problems with the ex-up before, but i wasn't going that fast.
I hit the kill switch to reset the exup and fiddled with the cables to see if one was broken. I got about 5km and it semed to die.
I think if I had kept it up in the higher rpm it would have kept going.
So I pulled up at a street light. It would have kept going if i hadn't had wanted to stop.
. Started it up about 5 mins later and went about 20ks till I thought I would see if it would die if i gave it full throtle, it started splutering and i went about 2km and came to a stop and would not start.
Had heaps of battery power but started when i bumped it.
Home was about 2ks away and no problem. Started after I stopped it no problem.
I played with the exup this morning seemed to be ok just went about 4ks and went home when I pulled up at home and put the bike into neutral it stopped. The plugs r just coming up for 6000ks is that a problem
.please help.

 

p.s the bike is a 3ln1 and dus not seem to have a fuel pump or a fuel line filter is it in the tank ? <!-- s:-? --><img src="{SMILIES_PATH}/icon_Eyecrazy.gif" alt=":-?" title="Eye Crazy" /><!-- s:-? -->

 

ooooh damn.

1. Get a filter, right away. The tank has inlets that strain and sort of filter the fuel from large floaties, but it's definately not good enough. Single use filters are ~ $4

2. Find a pump. $150 for a universal 5 or 6 psi fuel pump. I *think* that it's triple-phase. Fuel pumps can have a gajillion psi and will still work fine - they only provide what is asked for by the carbies. Remember that bit of info when getting one from a wrecker who keeps umm-ing and arr-ing about the pump. I'm about to get an FZR 1000 pump cos its the same. I think the fuel line plug is 6 mill thick.

You'll notice with a filter and no pump that when there is less than 2 litres in the tank the bike can't really rev far, because when you pin the throtlle more air gets in, but less fuel follows due to flow restriction, so the bike peaks at a low rev count and just runs super lean. (You'll feel the bike winding down. If you let the throttle in at this point you get a bit of a kick out of it!)

 

no. (response to original question - not Timbus's response)

Many fuel pumps were removed (not fully sure why - people probably get rid of them to rule out one potential problem source, though most are probably fully functional). You don't necessarily need one on a 3ln (you will be able to use all but the last litre or so wtihout hiccups). But advisable to get one - as per Timbus's response

Definitely get an inline filter though. Cheap, and could save you lots of problems in the future.

 

I spook to sumoto and they sed they run beter with out the pump .The problam was a fual block on my bike in the tap. Thanks for all your help and I will be geting a filter today.

 

I've noticed that a fuel block can present itself as a fuel overflow. It splutters and somewhat backfires even though it's missing fuel. If you had a blocked line I suggest you clean and de-rust your fuel tank. Best method (I think it beats tbones) is to get food grade citric acid, mix it with water, bung it in and shake it like bugghery. Then let the citric - water mix touch all the tank's sides for a minimum of 2 hours. When done, shake it up (maybe with some rocks or nuts to free the rust) and then flush it out with water. Citric acid loves rust. That'll de-rust it.
500mls of epoxy resin keeps the inside of the tank form ever, ever rusting again right up until the day it gets to the junkyard.

PS. Sumotoworld eat ...... Get a pump. Why would a bike run worse with a constant fuel flow? They just cut corners to save costs man.

PSS. If theres a fuel block in the tap, the small internal tank filter may be missing. Bad...