Sportbike World banner

1 - 16 of 16 Posts

·
Registered
Joined
·
8,798 Posts
Discussion Starter #1
The motor doesnt start as easily as it used to. At first just touching the starter button was enough to get it purring. After a while it had to be cranked longer, thru maybe 3-4 revolutions. Now, it fires after about 3-4 revolutions, but the first 2-4 revolutions under its own power are slow, uneven, and generally sound bad. After that the engine evens out, and everything is well. If its warm, it starts right up with no issues. Before this recent development, the bike set for a few months in disuse.

So what gives?
The plugs are still original, so they probably need replacing (16k miles on the clock)
Air filter is relativly new, oil is fairly fresh
Dirty injectors? I havent run any cleaner thru them in recent memmory
Its done the same thing on different tanks of gas, so I'm pretty sure its not bad gas.
Something else? Bad mass airflow sensor, or air temp sensor? no FI codes given
 

·
Strength and Honor
Joined
·
6,144 Posts
Are you saying the turnover sounds strained? How about battery? All water fill points correct? Battery holds a good charge and is fully charged?
 

·
Registered
Joined
·
8,798 Posts
Discussion Starter #3
Guess I wasnt clear. The turn over sounds fine, the starter seems to work great.
How about this,
In the first year: touch the starter, the engine fires on the very first revolution
After a year or so: Touch the starter, the engine turns over twice or 4 times, before firing. Insdead of inna-vroom, its more of a inna-inna-inna-vroom. I wouldnt say its hard to start, just harder than it used to be.
After this last break: hold the starter for a few revolutions, then engine fires, but the first few revolutions under gas power sound like the engine is about to die, the idle is real rough. After a second or so the idle smoothes out and everything is fine and dandy. So its a inna-inna-inna-vroo,cough-vroo-pause-vroom-vroom-vroom.
Side note: had the gas tank off and the fuel pump out this last break, and while I tried to keep everything very clean, I suppose something could have gotten in there and clogged up the fuel pump.

The more I think about it, the more I suspect the plugs.
 

·
Registered
Joined
·
369 Posts
Oh, I most definitely would suspect the plugs. I'm sure you're overdue for a replacement.

Get some Iridiums. I got 40,000 miles out of my last set and they could have probably gone longer.
 

·
Registered
Joined
·
8,798 Posts
Discussion Starter #5
Any idea how deep I have to get in there to change them? I'm guessing take off fuel tank and air box, but hopefully I wont have to take the throttle bodies off...
 

·
Registered
Joined
·
369 Posts
I don't know about the ZX10 specifically, but normally you just need to prop the tank up and remove the airbox. It's not a big deal.

Also, don't pull all of the plugs at once. Depending on how loosely or tightly your plugs are wired, you could possibly lose track of the firing order.
 

·
Registered
Joined
·
8,798 Posts
Discussion Starter #7
Mister Tee said:
I don't know about the ZX10 specifically, but normally you just need to prop the tank up and remove the airbox. It's not a big deal.

Also, don't pull all of the plugs at once. Depending on how loosely or tightly your plugs are wired, you could possibly lose track of the firing order.
Thanks! thats just the sort of mistake I would make and then have to spend 30 minutes looking it up
 

·
Registered
Joined
·
8,798 Posts
Discussion Starter #9
Xx954HxCafexX said:
you dont have a factory service manual vash?
Its a PDF saved on my desktop. I print the section I need before I start working on something. Why?
 

·
Registered
Joined
·
352 Posts
Vash said:
Any idea how deep I have to get in there to change them? I'm guessing take off fuel tank and air box, but hopefully I wont have to take the throttle bodies off...
cause of this post, yea i got my manual pdf, printed it all out and put it in a 3 ring binder.
 

·
Registered
Joined
·
369 Posts
Another hint - if this is the first time you've replaced the plugs (obviously it is), it might be a good idea to write down your available plug socket sizes and make sure you have the right one while you're still at the store buying your plugs. It's also a good idea to get a u-joint too if you don't have one - I have to use a u-joint socket extension to get the two outer plugs in my gix.
 

·
Strength and Honor
Joined
·
6,144 Posts
Yes, the Kawis are just tank and airbox. Quite accessible.
 

·
Registered
Joined
·
8,798 Posts
Discussion Starter #14
Thats something I ran into on my first bike, while replacing plugs. The bike's tool kit had a cheap u-join socket that worked to remove the original plugs, but the ones I purchased used a different socket size.
 

·
Strength and Honor
Joined
·
6,144 Posts
Speaking of that, on the 636 they have this 21mm or 22mm female bolt to get the front tire off. Turns out the 13/16" spark plug socket has that same size hex on it so most have opted to use a 3/8" extension and their spark plug socket to get it off rather than special order this monstrous Allen wrench.

Just an interesting :topic: I learned.
 

·
Registered
Joined
·
8,798 Posts
Discussion Starter #16
kanwisch said:
Speaking of that, on the 636 they have this 21mm or 22mm female bolt to get the front tire off. Turns out the 13/16" spark plug socket has that same size hex on it so most have opted to use a 3/8" extension and their spark plug socket to get it off rather than special order this monstrous Allen wrench.

Just an interesting :topic: I learned.
A good trick for those is to get a hex bolt that fits into the axle, and put two nuts on it. Then use a regular box end wrench on the inside nut.
 
1 - 16 of 16 Posts
Top