YPVS TONE

The screw bolt at the rear of the cylinder head next to the tappet cover on the RH side is according to the manual a "CHECK BOLT" which you just loosen as the bolt has a slit in it and then remove the smaller screw bolt on top of the oil filter cover then start the engine and make sure oil flows from both. If it doesn't after one minute stop the engine as there is a problem . Tony.

In the Yamaha service data book I have for the FZR600 1989-1993 it says 435ml per leg of 10 weight fork oil. Tony.

Did you set each cylinder to TDC on the compression stroke before you adjusted the valves ? Tony

Have you checked the fuses to make sure none has blown. Also put the key in the ignition and try wiggling it in the switch incase the switch is worn. Tony.

The LC and YPVS ignition system uses a wasted spark system where both spark plugs fire at the same time. To check the coil unplug the two wire orange and black wires multiplug that goes to the coil and check the resisistance between the orange and black wire of the coil.You should have 0.33ohms +or-10%. Now unscrew the plug caps from the HT leads and set the meter to kilo ohms. Insert one probe into the end of one ht lead and the other probe into the other ht lead.You should have 3.5kilo ohms +or-20%. Hope this helps .Tony

I have found an old Yamaha Technical service bulletin that was sent out to Yamaha dealers in the UK. Model : XV535 Subject : Ignition Failure Symptoms - Engine will not start,misfire or cuts out. Cause - We have found on some machines that this failure is caused by corosion of the joint for the red/white power feed wire to the HT coil,inside the main wiring harness. This can also effect the functioning of the fuel pump relay and cause the relay to "buzz" when the ignition is switched on to the on position. Remedy - Strip back the outer sheathing of the wiring harness as far as the joint for the red/white wire. If this joint is found to be corroded,repair and solder the joint. Replace the sheathing or tape up the wiring harnes to stop water entry. There is also a picture that shows the red/white power feed wire just above the front cylinder in the main harness. Hope this helps. Tony.

When you stripped the carbs did you put the floatbowls back on the right carbs as they are different. If you take the float bowls off you will see one floatbowl has a hole that goes to the starter/choke jet and the other is blanked off. The one with the hole must go to the LH carb (the one with the choke knob on) and the one that is blanked off goes to the RH carb. Also when you put the carbs back on make sure that the choke pipe between the carbs is connected. Tony.

Hi Steen Yes it's a genuine Yamaha data book I got from ebay a while back.It's a book that was issused to Yamaha dealers as a quick service referance guide for models 1984 -2001. Tony.

According to the Yamaha service data book I have for the XJ900 1985-1992 the CO Content% should be 4-5% .Hope this helps . Tony.

Isn't the battery under the RH side panel? I seem to remember it was on the earlier SR125. Tony.

I would go to your nearest Yamaha dealer who should have a parts list and show him the bolt your after which he can order .Tony.

In the data for the 78-79 XS500 I have it says 3500cc which is 3.5 Litres. Have a look on the RH crankcase cover as Yamaha usually stamp the amount there. You might need a bit extra if doing a filter change as well .Tony.

By altering the float so it shuts earlier you will actually lower the fuel level in the float chamber causing it to be starved of fuel at full throttle. What you need to do is take the carb off and reset the float height. Unfortunately am not sure what the factory setting is .Perhaps one of the helpful chaps here could tell you if they have a manual. Tony.

If it is the waterpump seal you shouldn't have to remove the engine as the waterpump/seal are housed in the RH clutch cover but you will have to drain the gearbox oil and coolant before you remove the cover. Tony.

If you mean the expansion tank for the radiator you want a 50/50 mix of ethylene glycol antifreeze and distilled water. Check the level in the tank with the bike stood upright and the level should be between the max and min marks on the tank .Tony.

Just had a look in the Haynes manual at the wiring diagrams for the F and N models and it shows a Red/White wire coming from the Kill switch going into a Red/White wire in the CDI unit. What are the markings on the CDI unit you have. Tony.

Have you had the valve clearance's checked ? .Tony.

Has the fuel tap got an OFF position if so try running the bike with the tap Off until the engine stops and then try turning the tap on. It sounds like the float has stuck or you have a bit of dirt on the float valve causing the leak or you could try turning the tap off and draining the carb floatbowl and then turning the tap on.Tony

In the haynes manual on the FZ600 it says the cams are marked "I" for the inlet cam and "E" for the exhaust cam. Tony.

Another check is where the tacho cable goes into the cam cover .From memory I think the tacho cable is held in with a cross head screw .Undo this and the cable should pull out and there is a small oil seal inside the cam cover .Tony.

According to the genuine Yamaha workshop manual for my Rd350lc2 if the flasher cancelling unit is faulty you can simply unplug it and use the indicators manually. Hope this helps . Tony.

Hi Janie The only thing left is to get the clutch stripped and the clutch plates checked for wear and replaced as if its been used as a test bike the clutch has probably had a hard life. Doesn't Alan Dowds now write for Superbike magazine ? Tone.

Hi Janie Glad to be of some help.I always think it's best to try the basics before delving into carbs as unless your carefull you can sometimes do more harm then good. Regarding the clutch slip do you know what oil is in the engine as you really want a 10w/40 motorcycle specific oil ( NOT car oil ) which has JASO-MA spec on the bottle and make sure you have 10 - 15mm of freeplay measured at the end of the clutch lever. Tony.