perhaps tune up??

Coming 'out of tune' so quickly is likely something relatively simple but very important. I'd be more worried about a gradual degradation.

The first thing I think of are spark plugs... If one of those wears out, becomes dirty, etc. it will significantly alter the performance of the bike - it is also an all or nothing deal usually (i.e. either it will be working fine or just won't work). A quick test - take it out for a short spin. Take a spray bottle of water and spray mist at the exhaust headers. If it is the spark plug (or perhaps plug cap) one of the headers will not be hot. This is an easy fix and would cost you about $20 to fix yourself (and about 3-4 hours of your time - this is being very lenient, can be done in under 30 minutes if you know what you are doing).

$250 is very reasonable for a full tune, but you should find out what they mean by 'full tune'! Make sure they clean/balance carbies, change oil & filter, change coolant, change spark plugs, check brake pads (and change if required), etc. I was quoted about the same, plus 'unexpected' parts - the one part that was expected to be used were new jets for the bike and these can be around $200 /set for the fzr250.

 

I'd definitely be betting on the spark plug still... Probably after it came back to life you had no issues, but once you let the bike cool down and then restart the problem will come back. I've experienced this in the past. Two options:
1) replace the spark plugs (should be about $20 for a set of 4 normal, or $70 for irridium - it takes cr8e or equivelant)
2) take the spark plugs out and clean them (I have used a wire brush to do this - get off all the carbon build up which is why it is not sparking well), re-gap them to 0.7-0.8mm, and put them back in.

Sometimes the plugs will just need a clean and are not worn out. You will be able to tell a worn plug (if not, check here: condition chart).

Theoretically spark plugs should stay clean if the engine is running optimally. But if you are in stop/start traffic they will foul up, or if you are running rich/lean you could run into problems (in which case a full tune-up would be a good option).

 

If it isn't the spark plug itself and the header is still cool it could also be the cap and / or could have some loose electrical leads to that one plug. My next check would be to see if the cap is ok (if you have a multimeter you can compare the possible 'dodgy' cap with an expected good cap). Check out <!-- m --><a class="postlink" href="http://faq.f650.com/FAQs/PlugCapsnCoils.htm">http://faq.f650.com/FAQs/PlugCapsnCoils.htm</a><!-- m --> and click on the 'testing the spark plug caps' link.

 

Although some-what difficult, the best way to check the plugs is to run (at operating temp) the bike up to say.... 10-12K (say 3 gear) and pull in the clutch at the same time you hit the kill switch. Make sure that you are accelerating right up to the point of turning off the bike.

Coast to a stop and check the plugs.

I know, WTF?!?! and yes, it'll be hot, but that is the only way to get a true reading of the plugs.

 

ok so, it doesnt idle, and it sounds restricted? hmmm does it sound like a ducati? (running on 3 cylinders) and it doesnt rev over say 12g? it just stays there when u hold it flat? has it been raining? damn i hate the rain <!-- s:cry: --><img src="{SMILIES_PATH}/icon_cry.gif" alt=":cry:" title="Crying or Very sad" /><!-- s:cry: -->

 

what i meant up there by holding it flat, the revs go up to about 8 or 12 or something and not any higher?

 

Damn exup's
Great when they work but are also a source of alot of headaches

 

Re: perhaps not tune up

What bushes would he be talking about? The valve itself is a piece of metal that rotates within the exhaust...

If it is the exup try wiring it open - see the third post in <!-- l --><a class="postlink-local" href="http://www.fzr250.com/viewtopic.php?t=441">viewtopic.php?t=441</a><!-- l --> . This will eliminate the exup as a potential source of problem. You may experience a very slight decrease in power at the low end, but once above 8000 revs it should feel normal... (there are a few other posts there regarding checking and adjusting teh exup - it is one of the easier things to do - don't even have to take main fairings off!)

 

actually i think i know what hes talking about... because my exup rattles as well because there is clearance between all off the moving parts. when looking at the valve from the side of the bike, the valve mechanism can move back and forth or inwards and outwards... there must be some sort of washer or bushing in there that will stop that sort of movement....

although i havent taken it apart to fully investtigate it...

simon

 

Ahhh! Now I get you. But how would that cause the problems described? Provided it can still open and close properly, rattling shouldn't be an issue... Or am I missing something? (i've only had one coffee this morning, so I may be...)

 

There is a bushing on the far inside, on the end of the valve. Grease (moly) if possible, replace as necessary.

 

no it probably doesnt explain the performance decrease... but it does explain the rattling at idle...

would a snapped exup cable result in such a significant power loss?

simon

 

have you checked the exup cables? cos if one is snapped or seriously loose, i guess it would rattle a lot more...

simon

 

FZR dude: I also have a problem with this exup rattle, but only at idle and low revs. Mine hasn't reached the stage of rattling while in the higher rev ranges.

I know this bush that you mentioned, and saw that you recommended greasing it. What did you mean by grease (mol)? I have had mine apart and can see exactly why it rattles - just because the butterfly valve has worn and has a lot of movement in it. Not sure whether greasing would fix it, but worth a try. Hi-temp bearing grease or somethign should do it, you think??

Also, I'm having a prob. where the bike seems to get vapour lock or something. usually when the tank is half full, not completely full, and has been standing for a while. When I turn it over, it will start fine, but after a few hundred metres it just dies in the ass, and seems to get worse the more I accelerate before it conks out altogether and won't start again. Once I have lifted up the fuel cap and let it sit for a second, it will start.

Anyone experienced anythign similar? A mech I spoke to suggested it could be somethign to do with fuel pump. Apparently some of the later models are meant to run a pump, but many of them have been disconnected when they were imported. This can cause fuel feed problems once the fuel level gets down a bit. Mine's a 3LN, and as far as I'm aware, it's just gravity feed, not even meant to have a fuel pump. Not sure on this though.
He also said adjusting float heights could help, but warned that this can also mean it will run badly in other conditions (hot/cold, can't remember which).

He just basically said the FZR is a finnicky model of bike, you can never get it running right all the time. I guess that's why it was only produced for a period of about 5 yrs or so, unlike the CBR which has been around much longer. After the small but annoying and costly probs I've had in my almost 12 mths of ownership, i'm inclined to agree. Maybe I will rethink my goal of stepping up to a YZF R6 as my next bike, if they're based on the principles of the FZR250...(sorry for the long post guys - I write and edit for a living so can get carried away at times!)

 

fizzer
what year is your 3ln? i have a 1989 3ln-1 and it has a fuel pump... if you can here a noise coming from under the seat/tank area when you flick the kill switch to the 'on' position, then it has a fuel pump.... im pretty sure thats the sound of the pump priming and pumping some fuel into the fuel lines... when youre low on petrol, it primes for ages ....

if you have no idea what im talking about then i guess it doesnt have a fuel pump...

my bike can be temperamental too but it rarely just cuts out while riding unless im low on fuel.... i was under the impression that the hesitation and the trouble starting the bike after stopping would be helped by fully servicing and balancing the carbs.... when i get it done ill let you know ...

simon