RiderForums.com - Kawasaki Motorcycle Forum banner
1 - 8 of 8 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter · #1 ·
I have a 2000 kawi zr7 that i acquired 2 months ago. The bike would start fine when cold (80 degrees outside) and then all of a sudden bike wouldnt start without starting fluid when cold. Bike has always run a little choppy so i changed plugs, oil, added fuel treatment (93 octane gas only) and pretty much did the basics. So 2 weeks ago it just went capoots and wouldnt stay running unless it was just low idle and even then choppy. Drained the gas and out of 5.5 gallons id say maybe half gallon was water. Drained that cleaned tank real good cleaned petcock and sprayed the crap out of carbs with carb cleaner then drained em and repeated that a few times til i no longer smelled gas. Got it all back together started fine ran it around town maybe 20 minutes and was choppy the first 3 minutes but then ran mint. I went to start it next day and wouldn't start without the starting fluid again but ran good other than that. Bike starts great once its warm but I could really use some help here. I dont think its a vacuum leak but honestly idk forsure. Any insight would be much appreciated bc im ready to throw a match on the thing
 

·
Registered
Joined
·
4 Posts
Discussion Starter · #2 ·
I also put a brand new battery in the bike when I got it. I have no idea of mileage bc some dummy took the tac and Speedo off to replace with some cheap Chinese Speedo that doesnt even work
 

·
Registered
Joined
·
428 Posts
Where did it get the water in tank from?? Would it start better if you primed the carbs for a few minutes prior?? Would it run better with petcock in Prime position? Have you checked level on bowls?

If you don't know much about this motorcycle, or even the mileage, I'd would remove the carbs and do inspection and thorough cleaning and float level check, which is about basic after acquiring a very old vehicle. It is 20 years. Sounds like you are simply spraying cleaner on the outside, or through the air box which is not very elegant.....it won't solve the problem. Starting fluid won't either

.....also I'd plan on checking valve clearances and see how that is doing. 93 octane would not do much on an engine with 9.5 compression ratio., It is OK, but likely you are wasting your money.
 

·
Registered
Joined
·
4 Posts
Discussion Starter · #4 ·
Where did it get the water in tank from?? Would it start better if you primed the carbs for a few minutes prior?? Would it run better with petcock in Prime position? Have you checked level on bowls?

If you don't know much about this motorcycle, or even the mileage, I'd would remove the carbs and do inspection and thorough cleaning and float level check, which is about basic after acquiring a very old vehicle. It is 20 years. Sounds like you are simply spraying cleaner on the outside, or through the air box which is not very elegant.....it won't solve the problem. Starting fluid won't either

.....also I'd plan on checking valve clearances and see how that is doing. 93 octane would not do much on an engine with 9.5 compression ratio., It is OK, but likely you are wasting your money.
After talking to a few mechanics and hours of reading forums I'm pretty sure its the valves. I didnt take the carbs off and open them up but i took the airbox off which was pretty damn cobbed and sprayed them like that and with the throttle open. When running the bike has valve chatter on the left side (cyl 1&2) but nothing on the right side and its a very noticable difference. It also eats gas, only runs with petcock on prime and when letting off the throttle anywhere over 4k rpms it pops and back fires. Someone tried turning it into a stunt bike (like a moron) so im sure this things been pounded on. As for water in the gas said moron before me installed a fancy chinese gas cap and never cranked the bolts down to seal the rubber gasket properly and unfortunately living in upstate NY we see ALOT of rain and it was leaking into the tank through the cap (I assume).
 

·
Registered
Joined
·
428 Posts
Like I said, going thru the carburetors thoroughly is one of the first basic things you do on these old ladies. Disconnecting/connecting throttle cables, and realigning 4 air intake boots, are about most tedious part on carb removal. The carbs themselves are very easy once you understand the basics. Wonder if idle mix screw epoxied lids have been removed????

The petcock is vacuum operated when in 'ON' position, by engine running. I'd make sure it is really opening, and has hose behind. "Prime" simply bypasses the vacuum system. "RES" simply opens to the short filter on bottom of tank, top of petcock(there is no "reserve" per se). Having a transparent fuel filter between petcock and carbs helps immensely verifying fuel flows.

Checking valve clearances is rather easy, but replacing shims if you have to,.... a bit more involved,...... as camshafts have to be removed, but if that time comes and you ask for tips about this, they shall come...... ...and if you are keeping the bike, get a factory manual...it would make your life a lot easier....they are also available on PDF.
 

·
Registered
Joined
·
4 Posts
Discussion Starter · #6 ·
Like I said, going thru the carburetors thoroughly is one of the first basic things you do on these old ladies. Disconnecting/connecting throttle cables, and realigning 4 air intake boots, are about most tedious part on carb removal. The carbs themselves are very easy once you understand the basics. Wonder if idle mix screw epoxied lids have been removed????

The petcock is vacuum operated when in 'ON' position, by engine running. I'd make sure it is really opening, and has hose behind. "Prime" simply bypasses the vacuum system. "RES" simply opens to the short filter on bottom of tank, top of petcock(there is no "reserve" per se). Having a transparent fuel filter between petcock and carbs helps immensely verifying fuel flows.

Checking valve clearances is rather easy, but replacing shims if you have to,.... a bit more involved,...... as camshafts have to be removed, but if that time comes and you ask for tips about this, they shall come...... ...and if you are keeping the bike, get a factory manual...it would make your life a lot easier....they are also available on PDF.
Ive always been a rocket guy and love the go fast but I really like this bike for what ever reason lol. I'll take her back apart and pull the carbs and do like you say. I know if i had to do the valves i can but honestly id prefer a professional do it to be safe. The bike is a blast to ride and fpr what I paid i dont mind putting a few hundred into it
 

·
Registered
Joined
·
209 Posts
Ive always been a rocket guy and love the go fast but I really like this bike for what ever reason lol. I'll take her back apart and pull the carbs and do like you say. I know if i had to do the valves i can but honestly id prefer a professional do it to be safe. The bike is a blast to ride and fpr what I paid i dont mind putting a few hundred into it
True, it ain't no rocket but the thing moves pretty good once you get past six grand.

Anyway, I'm in agreement with a carb rebuild and definitely a valve clearance check. Even if you're not comfortable removing the cams it's pretty easy to at least check the valves. Your running issues may well be there. My new to me zr7s now runs like a champ since adjusting the valves (and rebuilding the carbs and new carb holders and air filter and plugs).

There is an excellent tutorial here for adjusting the valves. It's not that hard as there's only eight. The worst part, for me anyways, was scraping the old gasket.
 

·
Registered
Joined
·
4 Posts
Sounds like a blocked jet in the carbs, most likely one is the needle jet. Just which one is the bit that will take time. Tank cap is meant to form a good seal when closed so double check where the water is getting in. Valves are easy enough to do with the right tool, just time consuming when you grind them in. Also check spark plug and it’s colour, no joy with any of this check timing
 
1 - 8 of 8 Posts
Top