20 Most Recent 1990 Yamaha FZR 600 - Page 7 Questions & Answers

I can only answer the plug test question. Unscrew plug from cylinderand re-connect to the high tension lead with ignition off. Now rest the plug against the cylinder head but only hold the high tension lead. then with ignition on push the kick start lever or activate starter if fitted. if the plug is touching the cylinder head and is working properly it shoul be sparking. Note: only the side of the spark plug should be touching the cylinder head so that you can see the spark. Hope this is clear for you.

Hi the rectifer will get warm as the machine runs, the fact that the old one burned out could simply be as a result of ageYou will also find the wires to the rectifier will also get warm close to the unit, assuming it does not blow a fuse, and that the correct fuses are fitted, and the battery is in good condition, a discharged battery could cause the rectifier to burn out, as the battery acts as a form of resistor for the unit, on some of the older machines like yours the charging system did not work, unless you had 12 volts in the battery to supply the DC side of the alternator

It will not be a bent shift fork. If the clutch lever feels the same pulling the lever in and out as it did before the problem came up then chances are the clutch is okay. Does the lever at the gearbox move properly when the hand lever is moving in and out? Is the clutch cable hanging up on something? I think you are going to find either a broken woodruff key on the gear at the right end of the crankshaft or clutch plates hanging up on the clutch hub. The broken key would prevent power from going to the ring gear on the outer clutch hub. The clutch plates can wear grooves into the clutch inner and or outer hubs. Too deep a groove and the plates can be unable to be compressed by the clutch springs. The result is no power being transmitted through the clutch. Another possibility is a broken shift shaft arm or arm spring. The right engine side cover will need to be removed so you can then do a visual inspection of the crankshaft gear, clutch hub and shift shaft lever. If I knew the year and model and engine size of your Yamaha bike I could offer more exact diagrams. The one below are generic. Go to www.babbittsonline.com and you can see an exploded view of your specific engine. Please rate my answer.

There is a number of different things tha couldt cause this problem.
1.The wiring to the headlight from the handle bar switch could be broken.
2.The headlight earthing could be broken.Check to see if you have voltage to one of the bulb terminals then if you have then run a wire from the case of the bulb to the battery earth (-) and if the light goes then the earthing is broken/faulty.
3.The high beam/low beam switch could be faulty.
4.The contacts that touch the bulb terminals could be damaged or broken.
Gd luck.hope this helps

When engines get too hot, it can cause a number of problems, blown head gasket, warped or cracked head siezed pistons, heat softened rings, causing high oil use,etc
Running low on oil can cause a whole lot more problems, to bearings , cynlders, cams etc
It sounds you will need at the very least , new rings ,and head gasket

easy way is to follow from tank valve to carb

Hello
You must have gotten the carbs set up wrong. I assume you used a carburetor synchronizing tool called a "Manometer"? You can either have mercury columns as a balance er or vacuum gauges, make sure the engine is fully warmed up and at the proper idle speed and you have a fan on the carburetors. I suggest you bench sync the carburetors 1st then using the idle mixture screw fine tune them on the engine, they will be very close. Here is the procedure for bench syncing.

To bench sync the carbs. Pull the carbs, run the idle knob all the way in to open up the butterflies. Using a the smooth end of a tiny drill bit as a feeler guage, adjust carbs 1 & 2, than 3 & 4, then make sure the two sets are matched by using the center adj. screw and guaging carbs 2 & 3. Once finished, back the idle adj knob all the way out, and then screw in until you see the butterflies just move. This should set you back to just about correct on idle.

Now more fun Provided the the carbs are bench synced with great precision and patience, there are no vacuum leaks, and you own a carb sync, you can now go back and re-sync the carbs using the idle mixture screws. This will be touchy, as very small variations in the screws will be
needed to get all the carbs mixed evenly. Isolate the sync from vibration by holding it up on something other than the handlebar. Adjust the idle mixture screws ever so slightly to even out any variation that the sync shows. Gently increase rpm, and you should notice the sync rise more evenly than before. And there should be little if any variation in sync levels at 3k rpm. The bike should cruise at 1/8 throttle much smoother now. And all light handed acceleration will be much stronger too. Ideally, an Exhaust Gas Analyzer should be used to do this. The nice type that uses a insert on each header pipe to read CO2 and give perfect stoichiometric air fuel burn ratios is the best way to make sure the carbs are super dialed

Sounds like your carbs are clogged, leaving choke wide open or staying on throttle to force running conditions merely tries to bypass the pilot jets but ultimately the carb needs to be thoroughly cleaned and if the gas is pretty bad you will need to flush your fuel tank out as well.

Remove the ride side case cover. Next remove the rotor using an impact wrench and rotor puller. now you can get to the stator to remove it. Please rate my answer. .

Use just a couple of drops of super glue. It holds the rings and then the heat from the exhaust destroys the glue. Works perfect! Please rate my answer. Thanks.

put a multi meter across the battery terminals.
bike not running 12v or a little more
bike idling 12.5 v
bike 2-3000 rpm should rise to around 14v

These are not exact voltages, but if there is no rise when the bike is revved, there is a problem with the regulator or stator.

Not sure on that particular model, year , but if it cant be seen under the seat or side cover, it may be inbuilt in the alternator.

This sounds like the clutch has gone out and needs to be replaced, it is very unlikely for the shift fork to get bent on these bikes.

yes it could. Try replacing with the same volt and amp and check

There is a couple was to look at this. 1. Write down your VIN and call a Yamaha dealer. They may be able to help.

2. There are VIN look up on the internet that may be able to translate your VIN over to which size your engine is.

Hi,,,,,,fork seals are to stop oil coming out of your forks,,,,if your forks have oil on them ,then the seals need replacing.(you cant fix them)


hope this helps

if the battery is taking (and holding) a charge, my guess would be the voltage regulator, whitch if i remember correctly is located in the side of the rear cowling on the left hand side (a silver / black box with cooling fins on it) hope this helps

look where the sidestand pivot bolt is....just above it you should see a switch with a plunger, so when the sidestand is operated the plunger moves in and out.

Did you check the "Signal" fuse in the main fuse box?

Link: http://www.fzrarchives.com/images/pa...carburetor.gif

Top right #38

It should be a little screw with a philips screw head on it. It will be right below your carbs on the left side.

You should also look into getting your carbs cleaned as that will FIX your problem and not just work around it.
If this solution was helpful please rate/vote for me.

Check the switch it is by the pedal make sure it is adjusted properly and moving freely sometimes they get sticky when exposed to alot of the elements and this part gets alot of wear. Should be checked regularly and adjusted . It should have a lock-nut assembly and is fairly easy to locate as it is right in the general area of the foot brake area.