FZRSupport: the FZROnline Archive

hello fzr people,

I swapped this fzr 1000 exup 1993 for my motor from a Gypsy about four days ago... It has been hacked into some semblance of a street fighter... except it has no.. speedo, rev counter, temp gauge, working lights... When i rode it home the first ten minutes took my breath away... loved it.. the rest of what turned out to be a 50 min journey timefor 20 miles was very disappointing.

I have just read an article written by a fellow yamaha (not fzr) rider which is so exactly what happens when i ride my bike that it's riduculous... EXACTLY the same symptoms....

Two of my plugs are well sooty and coked (plugs 1 &2) the other two are optimal (3 & 4 light tan)... Start off riding my bike everything is heaven, (if i dont increase the load and just poodle, will keep performing well) as soon as i start putting a bit of load thru it, using more of the rev range or higher speed dual carridgeway stuff, i get exactly the same as this fella... I checked the sparks and they all seem similar...

is it poss that my left coil is dying and when under load and getting hot? starts to struggle.. therefore not burning the mixture properly.. hence two very sooty/coked plugs???

could it be the CDI ignition ignitor, does this get hot as you start going a bit quicker????

These symptoms seem very specific and the contrast between the plugs is very definitive, there is probably an obvious answer? If you are a bit more clued up than I am.

I have included this guys description of the fault, purelybecause I couldn't have captured it better myself.. this is what he says..

Here's the story so far.. Buy the bike with about 43,000 miles on it at a local shop here in Tucson. Looks and sounds pretty good, but it's got rather loud, after-market pipes (definitely not Cobras or Jardines but maybe HG Krome) and a battery that has been sitting too long. Ride it home. After about 10 minutes, I notice a "miss" in one or both cylinders, at both highway and city speeds. Gets worse as I ride. My first guess is that the battery is preventing the ignition from putting out a good spark. Remove battery and notice fluid in all cells is below the plates. Refill with distilled water, and trickle charge the battery for a few hours. Can't keep it above 12V. Buy a new battery, and take a ride. After 10 minutes or so, the miss returns in all its ugly glory. Sounds like both cylinders, but can't be sure. Miss gets worse. Stumble home and pull both plugs. Black, dry and very sooty -- See http://www.dansmc.com/Spark Plugs/Spark_Plugs_catalog.html (picture #3). Carbon fouled from running too rich? Question => Can an ignition system do that, too? Seems unlikely that both carbs have gone south at the same time? Unless "somebody" tried to rejet them after installing the HG Krome pipes? Ugh!! Question => Would the HG Krome pipes make an XV1100 run rich on stock jetting? Question => What could it cost to have somebody rejet my bike to the pipes? Check each plug for a spark outside the bike (grounded on the cooling fins), and notice a reasonably "blue" spark (considering that the battery has to drive the headlight, the starter and the CDI ignition). But both plugs are "firing" all over the place -- at the gap, between the insulator and the side wall and so forth. OK, so an overly rich mixture (or something?) is eating the plugs. Then I remember that this bike has a choke. I look up at the lever, hoping that I left the choke on. No such luck. Choke is off, and after thinking about it for a moment or two, decide that wouldn't cause all of my symptoms anyway. While I'm standing up, I open the tank and check the gas. Maybe a gallon or so left in there, and only 83 miles on the trip-o-meter. Let's see, 4.4 gallons minus the gallon or so left is 83 miles divided by 3.4 gallons works out to 22.4 gallons per mile?!! Should be more like 35-40, acording to you folks on this list. Beginning to look like carburetion? Install two new plugs (NGK NBR7ES at $3 each). Get up next morning, and ride. The miss comes back after about 10 minutes, and gets worse. Dies twice in traffic waiting for a green light. Restarts each time (new battery?) but runs like !@#$%... Limp home, and pull the new plugs. Black, dry and very sooty. Check both air cleaners, but they look clean, with no evidence of having been wet or anything like that. The shop where I bought it is a good 40 minutes from home. To heck with that, I think, so I order a tow truck. It's coming Monday. Until then, I am very open to all suggestions as to how to fix this problem or remove my head from my sit upon. Hey, whatever it takes![/color]



my battery is good tho...

Please oh please master motorbike guru god's give me some divine intervention...

many thanks.

FZRFZRFZR.

1st off the coils serve cyliders 1 and 3; 2 and 4, so can rule out coils.

Deffo sounds like carbs, one way or another. they need strip down, float heights set, emulsion tubes checked for wear. One other thing, the 2 inside carbs have different jets to the outer 2, only a size or two, not really enough to make a difference. Worn tubes on the other hand can have a dramatic effect.

i hear the exup valve in the exhaust plays a big part in the peformance of an exup model

It's been sitting? Carb cleaning as Ice Queen said. Plus synch and new plugs. I say that a lot...wonder why?


Good luck

Two of my plugs are well sooty and coked (plugs 1 &2) the other two are optimal (3 & 4 light tan).

I would say that was your answer right there,check all the carbs are clean & synch them .
How to on making a synch tool is in the WIKI as is the Float height tool making.

Then buy new plugs and gap them to size and away you go ...................

Just did a "plug drop test on my bike"...

BY removing the cap from..

Plug 1 Engine cuts out from idle. (When i first got the bike on initial examination of this plugs it was very sooty/coked up.)
plug 2 Engine cuts out from idle. (When i first got the bike on initial examination of this plugs it was very sooty/coked up.)
plug 3 NO NOTICEABLE DIFFERENCE TO RUNNING OF ENGINE...!!!!!!!! (when i first got the bike the plug was light tan, in good order.)
plug 4 NO NOTICEABLE DIFFERENCE TO RUNNING OF ENGINE...!!!!!!!! (when i first got the bike the plug was light tan, in good order.)

Doe this mean that basically the engine is running off two cylinders, 1 and 2. (if so wouldn't the plugs be the ones in better conditon??)

Does this mean that the engine is getting no help from cylinders 3 and 4. (if so wouldn't the plugs be all gummy because they wouldnt be burning the mixture effectively??)(unless there is so little compression no mixture is being drawn in.. but how would the bike be so good initially when riding??)

Bear in mind the bike will tear your arms off for a while and will run consistantly at low rev riding.. for it to tear your arms at all it must be using four cylinders musn't it??

unless what i feel is tearing your arms off is actually very slow??

The problem of missing and poor power only starts when the engine has been under heavier load for while.. (say 10mins)..so it must be load or temp related.??

if you hold a white board up at the rear of the bike when its running you are getting some fine dirty oily deposits appearing on the card..

is this normal?


there is no noticeable smoke when riding. Havn't had the bike long enough to see if the oil is dissapearing...

The cap off the plastic water bottle overflow is missing and i noticed that the water was all over the rear brake caliper (after i had filled it up to max.) after riding, this may be due to hard suspension and bumps tho. I will fit a cap to it today with a breather pipe and try to see if the coolant is dissapearing???


Could it be a cracked head or blown cylinder gasket between 3 and 4 cylinders???


There is no white smoke from the exhaust when revving the engine...


Is it still possible that the problem may not be deep within the engine..


This all a bit disappointing in relation to how much effort and time I have put into the bike so far...should have done this simple test earlier perhaps

Any one got any ideas...

cheers chaps/chapettes.

...checking for cracking in carbs throttle piston diaphrams ; my 1994 fzr 1000 exup had a lot of problems for this .....; very little cracking can do very big problems ....