zxr250 engine timing...?

[grunge]

Is there such a thing... wait.. there probably is... what do we call it and how is it adjusted? (Not technically, I meant how do we know then it's at the right spot.)

The reason I'm asking is that before leaving work I was having a chat with an old friend (who I hooked on to netrider btw, as she was interested in getting her bike L's) at my bike when I started it.
We were having a bit of a chat, and just before I got my gear on to leave she mentioned "ooh, you might want your bike looked at, listen to the engine purring.." It was not in rhythm, and there was a couple of breaks in the rumbling.
She used to race cars, and she mentioned that its just akin to tweaking the carburetor or checking the timing belt (which I have no clue about.)
And once done it'll run a lot more smoother.

Does anyone have any tips on how to do this right for a total noob? Or is it just better to take it a mechanics?

Or..... "bikes are cars are different okay?"

Anybody?

[SuN~e]

ihave the same bike and working on it atm.
i did a heap of work on it...but in the end, i had to take it to a mechanic to do it for me. =\
my best option is to maybe sus out your carbs b4 u dig into the timing chain. maybe u need to clean them? (im a total noob so don't rely on me much)
mines running a little sluggish, it doesnt want to push on after about 14k,
my mechanic is looking into it,
but hey, if u got money, get a mech to check it out.

[grunge]

Well.. I'm a total noob too when it comes to bikes, and I'm a crap technical fellow. The bike's running fine, just that when it idles it's a little off.

Maybe I'll try to take it to a mechanic when it's due for its major service, see what happens... I'm able to do all the small stuff atm... or.. maybe give it more time I'll be more game to open it up.

[Saki]

off the top of my head i remember reading hte ZXr250 manual and it says that at 1500rpm it should b 15c advanced and 50c advanced at 15 or 16000 rpm!

[grunge]

Thanx for that Saki, except I'm so much of a n00b I don't know what you mean by 15c advanced or 50c advanced.

Could you please explain, like, to someone who has the BARE minimum knowledge?

Sorry to do this to you, I still wanna understand the theory.

[Gosling1]

Grunge - I'll take a punt and diagnose carbs that are out of balance. Any competent mechanic can fix this as part of a basic tune-up. You don't have timing belts ( unless you own a Ducati ), its timing chains or maybe gear drive if you are unlucky enough to own a Honda ( double )

You need to put your location in your profile, so the local KSRC crew can point you in the direction of a good workshop.

the 15 or 50 reference is referring to 'degrees of ignition advance', its a pretty simple concept, it refers to how many degrees of crankshaft rotation occur between ignition spark in the cylinder, and Top Dead Centre ( or TDC - ie the top-most point of the crank rotation.) BTDC is Before Top Dead Centre.

When the bike is started and idling, the degrees of advance are kept to a minimum ( eg 15 deg BTDC), to make the engine work properly at low speed.

As the engine speed rises with revs, the spark must be 'advanced' so that the engine works properly at higher speeds. ( Up to 50 deg BTDC, depends on the motor, some are higher, some lower.)

This is just a very basic description, if you are interested in how a motor works properly, read 'Tuning For Speed' by Phil Irving. This is a great book for understanding the basics of motors.

[Saki]

basically wat gosling said about timing,

[grunge]

Aaah, I see..... that all makes sense.

Well, I'm in the knox area.
The closest dealer I go to is Floyd Parkes, and I think I'm near Phil Tainton Racing...

and I'm close to the Ringwood area, which has a couple of bikes there... any reccomendations?

Thanks again. =)

[GForce]

for some reason, the zxr250 carbs get out off balanced often. i dont mean by fully off balanced but you will notice the power difference everytime you get the carbs tuned.
the honda cbr250rr are more consistant.

[Smitty]

Aaah, I see..... that all makes sense.

Well, I'm in the knox area.
The closest dealer I go to is Floyd Parkes, and I think I'm near Phil Tainton Racing...

and I'm close to the Ringwood area, which has a couple of bikes there... any reccomendations?

Thanks again. =)

go to PTR....they have a very good rep
stay away from FP Kawasaki (based on the gloom I hear about them)
and Ringwood??
my bro has his bike serviced by someone there
will find out if they are ok and let you know

cheers

[grunge]

Hmm.. I've jsut called PTR (haven't had much time these days..) and they say they only do larger bikes and they're swamped atm,otherwise they'd fit me in. Does anyone know any good mechanics who can do carb balancing for the bike - In the Knox/Ringwood area? THanks!