RiderForums.com - Kawasaki Motorcycle Forum banner
1 - 20 of 75 Posts

·
Registered
Joined
·
27 Posts
Discussion Starter · #1 ·
Hi Guys, I've subscribe to this forum from day 1 that i bought my baby.
1999 Kawasaki ZR-7 (naked)

i must say there are a ton of info on our bikes and i learned a lot.

my "problem" is that the bike in order to run ok....i had to take off the air filter cover

in order for you to understand the exact "problem", i have to tell you my bike's story
(my apologies for the VERY LONG TALK)

i bought the bike last year and it was running "ok" i must say....it was almost stock (only a Viper Muffler)
(haven't noticed the mpg back then)

after i've taken it for a general service....the mechanic(mechanic #1) installed bigger jets #110 (maybe because he saw the muffler and thought it would be better to install bigger jets)
(he also had to replace the jets on the bike because the stock jets were damaged....the bike was sitting for too long and original jets were blocked and the guy who sold me the bike, damaged the jets on his attempt to clean them)
after that, i had very big problem as i couldn't rev above 6k
so i took it back to the mechanic. he said that the bike needs more air so we need to order an aftermarket air filter.
due to my lack of free time cause i was doing 2 jobs, i told him to order the filter(instead of ordering it by myself)....after of 2 months of waiting the mechanic told me that he ordered it... but they didn't tell him that they don't have it....anyway....excuses...so 2 months passed and i still didn't had the filter
(he's a very good mechanic but here he did a mistake)

angry as i was....i took it at another mechanic(mechanic #2) that owed me some favors..... he installed the air filter K&N
also without asking me he played with the valves.... after that the bike was somehow ok...but not ok
i could rev a little above 6k but when i decelerate there was a VERY LOUD backfire...it can be compared to a shotgun shooting

so i decided to give mechanic #1 another chance.
so i've ordered the stock jets #108 and took the bike there

he installed the stock jet but the bike wasn't running ok.....after some tuning...the only way the bike could run ok was without the air filter cover
http://www.zr-7.com/Images/AirBox4.jpg (the rightmost part)

the bike now runs great without any problems....also installed a muzzy ignition advancer
i also purchased ivan's jet kit but it was impossible to install as i had the same problems as the first time (couldn't rev above 6-7k) due to lack of air

the bike as it is, runs great....but when i think that i am having stock jets plus air filter(more air)...why does the bike needs the air box cover to be removed in order to work ok?.....it's like having a stock bike with K&N air filter and race can and still needs more air to work ok
when i purchased that bike i didn't have this issues...there were stock jets with stock air filter and mufflet and it was working ok

my millage now is around 5.79L/100km
my best so far was 5.56L/100km (295.9 km with 16.45L gas 95-oct)
at around 285-290km i have to switch to reserve

most of my driving is in the city
here is my daily course:
https://goo.gl/maps/dY1um


i have seen posts here with some insane mpg...and ~230miles before reaching reserve
I've seen post from fellow riders like:
"I get 47.8mpg almost like clock work. DJ+K&N+Jardine+Scott Oiler. " - pattonme

shakennstirred - K&N,Dynojet,ignition advancer,Dyna coils,taylor leads,17T front sprocket,Nitron shock,hyperpro fork springs,Yoshi RS-3 ++59.5 UK MPG++

I get like 42 MPG(US) with K&N and a Muffler Only...
if getting my current mpg with the jet kit i would be even happier

i am guessing the "problem" are my valves that the mechanic #2 played with :jerkit:

what do you think ???


as you can see, i went through a lot of problems with my ZR7, i've even consider selling it or even setting it on fire.... but i managed to stay loyal and i am happy with it

i am just trying to get this obsession out of my head

thanks in advance

and again, sorry for the long talk
 

·
Registered
Joined
·
1,920 Posts
As for the air filter cover removal, have you checked for obstructions? These bikes were very lean when stock, and the air box design was a issue over 6k rpms. The Ivans kit addressed the problem by adding air holes to the lid in order to allow more air in and still be filtered and protected from debris/elements, and left the jet stock because of it. (you could try that and also cutting the snorkel end off that extends over the top of the battery) Another possibility, make sure your "choke" is properly adjusted. As for mileage, it varies...ALOT. My attitude is if it's running properly and gets better than my car, (30mpg) I'm O.K. as long as it starts, runs, and GOES good. As for valves, a good a sign of needing adjustment (too tight) is hard starting. BTW, WELCOME!
 

·
Banned
Joined
·
2,525 Posts
Ugh sounds like cheap guy being cheap is getting what cheap guy gets then complaining about it.

The mechanics you're speaking of, are they actual professional motorcycle shops or are these "mechanics" backyarders* that have turned some wrenches? Seriously, you took your bike to a mechanic that owed you a couple favors and he just starts playing around with the valves?

What diagnostics have been performed on the bike that lead to the changes these "mechanics" made?

Your mechanics sound like dipsticks (no offense, it's either them or you at this point). I wouldn't use either of them strictly going by your story.

* this isn't meant to denigrate people who work on their own bikes & cars. I'm one of these people. However, there's a big difference between those of us that know and accept our mechanical limitations and those that don't. There's a big difference between those of us that only do things if they have the proper tools, or not.
 

·
Administrator
Joined
·
2,727 Posts
You say the bike was running 'ok' with blocked and damaged jets....so your estimation of 'ok' is vastly different to mine. Your bike runs CV carbs, they usually rely on vacuum to operate efficiently....when you play around with air filters and airboxes of CV carbs, you have to know what you are doing. Larger jets just because of an aftermarket can....doubt it. Valve adjustment...doubt it...does it rattle like a dozen marbles in a tin can?, if not, then valve adjustment isn't the problem. ...maybe if the 'mechanic' altered the timing, then that's a different story (ignition advancer? just what is that)...seems to me that you have loaded your scoot with stuff that you heard was good and didn't actually go through the science of getting it all to work...take all the 'accessories' off it - start from stock...then...one by one....apply...it's a process of elimination, you will find out what the problem is...otherwise, you are just sorting through a lego box hoping to find answers.
 

·
Registered
Joined
·
1,920 Posts
WOW, lots of "negative commentary" but not much useful information, or suggestions there "Vic". Not to mention, I'm sure we've all experienced some "sub-par" mechanics in our day and faulty diagnosis? And BTW, an "ignition advancer" is a device that does adjusts the engines ignition timing. I am curious about what "running good" is tho? A short video with sound would do wonders for diagnosis purposes.
 
  • Like
Reactions: shakennstirred

·
Registered
Joined
·
1,396 Posts
the stock airbox has a small foam filter in the end, does yours still have that in ?. mine didn't have the small foam insert, but still had the white grill.
I removed the white grill to let a bit more air in and put some holes in the back of the box to let more air in, the white circles are where I put them
Land vehicle Vehicle Motorcycle Motor vehicle Font Architecture Building Mansion Estate Urban design
 

·
Registered
Joined
·
1,920 Posts
Good thinking Shaky, I forgot about that. That would qualify as an "obstruction"
 
  • Like
Reactions: shakennstirred

·
Registered
Joined
·
8,706 Posts
What Vic said might not be politically correct, nice, or friendly, but its 100% right.

With jetting, you cant just throw jets in, and hope for the best. What your experiencing is just what all of us went throguh back in the carburetor days.

There are several circuits at work in the carb, and most of them are adjustable.

Pilot jet, slide, needle jet, and clip position, and air screw are a few that come to mind. When you change the exhaust, ignition, and intake, it throws these all out of balance. Putting larger or smaller main jets in changes the carb is one adjustmentt out of many...

You need someone skilled to rejet your bike, not a parts changer.
 

·
Administrator
Joined
·
2,727 Posts
Thanks for the "advice" about the "ignition advancer"....most modern motorcycles (from about 1970) don't need it as ignition timing is dynamic - related to the revs of the motor.
 

·
Registered
Joined
·
1,396 Posts
Thanks for the "advice" about the "ignition advancer"....most modern motorcycles (from about 1970) don't need it as ignition timing is dynamic - related to the revs of the motor.
not so, there pegged back to help emissions etc, so most bikes are about 2-6 degrees out from were they run there best.
yes most bike have dynamic timing but its moving between there set rate which is like I said a few degrees out for optimum.
the ignition advancer puts it back to how the manufacturer really wanted to have it when it was designed and not where they were forced to have it to get it to pass the tests.
my cbr600 and my ZR7 run a lot better with one fitted.
 

·
Registered
Joined
·
1,920 Posts
What he needs a knowledgeable mechanic to address/diagnose whatever is wrong. I base this on his claim, that he installed a Ivans kit and saying it didn't work? That kit has been installed by MULTIPLE people with great results (myself included) and the claim it didn't work/help leads me to conclude that there's another issue(s) that needs resolving. And like already expressed, stop adding "stuff" like advancer units, slip-ons, etc...until it runs like it should. He (The OP) needs to respond here.
 
  • Like
Reactions: shakennstirred

·
Registered
Joined
·
1,396 Posts
as said go back to all stock, the end can will be ok to keep, but everything else stock and start there.
once its running good add the addons
was the valve timing done with the ignition advancer on ?
i's say get them set with stock rotor so timing marks are correct, then after add the advancer
 

·
Banned
Joined
·
2,525 Posts
WOW, lots of "negative commentary" but not much useful information, or suggestions there "Vic". Not to mention, I'm sure we've all experienced some "sub-par" mechanics in our day and faulty diagnosis? And BTW, an "ignition advancer" is a device that does adjusts the engines ignition timing. I am curious about what "running good" is tho? A short video with sound would do wonders for diagnosis purposes.
As I freely admit, I'm not a professional mechanic. I cannot give advice based on the given information, and frankly neither can anyone else. Just more wild guesses. Dispensing advice based on this story is just more "throw bigger jets in it" and "adjust the valves". If I said "have a valve job done" would this have really been more helpful, carryall? No it would jsut be as wild and stupid of a guess as everyone, including his stupid mechanics, are making.

Before I can give any advice that would actually be helpful, I need to know what diagnostics were performed. If it was NONE, then my advice would be to take the bike to a mechanic and have it PROPERLY DIAGNOSED.
 

·
Registered
Joined
·
1,920 Posts
So you admit that asking for more info would have been more useful than just the insults. like previous post said... I agree
 

·
Registered
Joined
·
1,396 Posts
if someone cant help then don't post
calling the poster cheap n dipstick isn't needed and frankly reflects bad on you.
and people wonder why people wont ask questions if the get reply's that have a dig at them
 

·
Banned
Joined
·
2,525 Posts
So you admit that asking for more info would have been more useful than just the insults. like previous post said... I agree
HAHAH this is a joke right? You do realize I asked the questions necessary to try to get the actual information to try to help with this situation? No..no you don't. LTR.
 

·
Registered
Joined
·
1,920 Posts
I'm sure the OP will miss your warm, sparkling conversational skills in his quest for help with his motorcycle, should he return. (doubtful) LOL but what do I know? I'm just one of those people making "wild and stupid guess's"
 
  • Like
Reactions: shakennstirred

·
Registered
Joined
·
27 Posts
Discussion Starter · #18 ·
As for the air filter cover removal, have you checked for obstructions? These bikes were very lean when stock, and the air box design was a issue over 6k rpms. The Ivans kit addressed the problem by adding air holes to the lid in order to allow more air in and still be filtered and protected from debris/elements, and left the jet stock because of it. (you could try that and also cutting the snorkel end off that extends over the top of the battery) Another possibility, make sure your "choke" is properly adjusted. As for mileage, it varies...ALOT. My attitude is if it's running properly and gets better than my car, (30mpg) I'm O.K. as long as it starts, runs, and GOES good. As for valves, a good a sign of needing adjustment (too tight) is hard starting. BTW, WELCOME!
first of all, thanks for the reply

i don't know much about engines and stuff....so i don't want to play around drilling holes as i will also need to recalibrate the jets
the best thing i can check is whether there are any obstacle in the air box.
 

·
Registered
Joined
·
1,396 Posts
you already have the ivan jet kit so its all there, it tells you what jets etc
I just put the holes on the back where I thought its better protected from any water getting in.

also don't worry about the back firing sound(its not really backfiring), its just the air bleed system helping to burn off any fuel left in the exhaust and its normal to hear that once you add a new endcan that's not stock.
 

·
Registered
Joined
·
27 Posts
Discussion Starter · #20 ·
this is my first bike and i don't know much about bikes.
i learn how to drive on it and even did my driving test with it.

when i say the bike was running "ok", back when i remember the only "problem" was hesitation, some backfiring and the one time that i WOT (and that was when i was on my way to the mechanic for the general service) the bike seemed to hesitate.. but as i said...that was the FIRST time i WOT the bike....
after a year of driving it and got used to it and after driven more bikes, if i had that knowledge back then..then i might have told you that even before the first service there were problems that back then i couldn't see
 
1 - 20 of 75 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top