zxr250c technical question

[timmyrocks]

guys i didnt expect a reply straight away i understaned that i wouldnt get one, i just can't stand pointless posts!
to eliminate the easiest thing i filled her up and took it for a run and still the same problem
i thought that the battery was mainly used for starting and then the alternator keeps the bike running and charges the battery? correct me if im wrong....
might have to strip the carbies and give them a clean and stuff is balancing them an ass of a job?, and does anyone have the required tools to do so? like a mercury guage and a vaccum guage they wouldnt mind lending me?
to try an easy fix do u reckon spark plugs would be a thing to try before stripping the carbs and possibly causing more problems then i already have?
also it revs fine untill it hits 16,000 if the carbs are blocked do u think it would rev ok till 16,000? or maby at that revs it needs so much fuel and because of a blockage or poor balancing it just cant do it in this state of tune?
cheers Tim

oh n is that better guys hehe

Heaps...Thanks!

Now, it sounds more like a lack of fuel than an electrical or spark glitch. From what you say, it doesn't sound as though it's breaking down, more just not pulling past 16. Things to check is the filler valve to ensure it's not getting an air lock, then fuel pump next. Sometimes as they get to the end of there life they get a little lazy. Yamaha's are well known for it.

However, I would fit a new battery before anything else and check the chrging system. If the battery is absolutely knackered, the charging system, may not be able to throw enough into the knackered battery to hold enough for sparking duties.

thats right it doesnt loose revs or anything it just doesnt keep goin and sits on 16,000rpm
it doesnt have a fuel pump, wheres the filler valve?
i checked the charge at idle and its at 14.6 and battery held its charge from yesti and was able to start it today on it so its not completly knackered just doesnt hold its charge for more then a week

[timmyrocks]

Try looking at the simple things
Fresh fuel
Plugs
Air filter - clean or replace
Battery - if it is considered to be going bad replace it so that it may provide a decent chance of putting out a consistent voltage.
Does it rev past this point in the garage?
Does the throttle cable actually open the carbs fully?
Choke fully disengaged?
Stand in the dark with it running and blip the throttle looking for arcing - even tune in an am radio nearby and see if it pops or cracks in time with the engine.
Cleaned the carbs recently? if not then have a go. While your at it then set the float heights and sync them. Take your time. Easy once you know how but daunting if you haven't done it before.
Possibly the coils are breaking down too with the higher RPM.
It is either going to be fuel or electrical - go from there
Very difficult to diagnose though without more detailed info.
The other thing you will find too is that not many people have had much "Valid" experience with these bikes. They are mostly owned by the relative newcomer who, whilst well meaning, actually doesn't know much more about them than you may but is still willing to give you bum advice. Personally never touched one hence why I ask if it had a fuel pump. I recently had an FZR250 in the garage and I learned that they can be notorious for dodgy pumps. Similar era and same capacity.

fuels fresh
plugs i will change before stripping anything
new air filter 2 track days ago, but will still check and clean
throttle operates fine
choke is fully off cleaned carbs when fitted to engine bout 3 months ago and checked float heights didnt sincronise them as i didnt have tools to do so
new coils fitted with plugs
might go out now and check for spark as its pretty dark atm
cheers for your help Tim

[robracer]

cool,
it just sits at 16,000 like rev limiter has kicked in goes a bit above, sorta sounds like its starving on fuel or spark


anyone compitent on balancing carbies and such that lives near greystanes NSW willing to help/teach me theres beer in it for ya hehe

The last post made a hell of alot more sense tim

What position is the choke in & could it be stuck on slightly or the cable stuck?

[Slow and wobbly]

Very difficult to diagnose though without more detailed info.
The other thing you will find too is that not many people have had much "Valid" experience with these bikes. They are mostly owned by the relative newcomer who, whilst well meaning, actually doesn't know much more about them than you may but is still willing to give you bum advice.

For an example of poor advice and an even worse desrciption of the problem I have to direct you here. Read the whole thread its a hoot!
http://www.fzr250.com/viewtopic.php?t=2 ... own+engine.

[timmyrocks]

nar checked that and the choke fully releases cable is in it good nik and it also has a spring on the carby for the choke to be fully retraceted

[timmyrocks]

hey guys fixed the problem and you would have never guessed it lolz.
i was thinking to my self what have i done since it was running sweet? only thing i done was oil and filter, drained carbies, removed spedo, oil n filter? not likely, carby draining? nah, spedo??? hrm so i connected it back up not the cable drive just the wiring loom and perfect, revs like a biatch now and is running A1 cheers guys for your help in trouble shooting this matter lolz what a funny outcome ay?

cheers Tim

[brendanzxr]

all good now tim now we can rap it out on the track with both our bikes

[Slow and wobbly]

?
Wow now theres a plethora of time to work on punctuation and grammar.

[robracer]

Tim I had a CBRR250 that has the same wiring to the instrument cluster & for the race bike I had to pull out the little black box & keep it plugged in & straped to the fairing mount...... good find on your part! ......pity we did not know that your instruments was missing in action

[robracer]

?plethora

Keep it simple Adrian

[timmyrocks]

to be totally honest i didnt mention it cause didnt think it would have anything to do with it hrm, just thought of it and ey it wouldnt have hurt trying it and yer fixed it wierd i know so i guess i am stuck with my spedo might have to put some tape over it like u said Rob so i dont look at it instead of the track
cheers Tim

[mike-s]

2 things,
1) Always remember anything could be the cause, dont discount it!!
2) shifty, read that fzr thread, Jesus H Christ what a pack of muppets.

[robracer]

I just went back & had a read of the fizzer post's OMG is this guy for real?
I cant even imagine how this guy menages to get out of bed each morning