top end noise

[zigzag]

hi there guys ive had my 1985 43f for 4 years now ,ive done about 12,000 miles on it . the total milage is now 30,000 . about 6 months back i started to hear a ticking/tapping noise it has got a little worse lately. it seems to be coming from the exhoust tappet area , i did check them about 500 miles ago but all but one was in spec , one exhoust tappet was a little tight but no problem. after adjustment the noise did seem to get a little worse. so my question is do the tappet adjusting screws over time mushroom in on themselves giving me a false reading with the feeler gauges . i know this can happen on some old cars , fords etc . have you guys any thoughts , or has this happened on your old xt . thanks zigzag

[Mezo]

Does the tapping sound get quieter when the engine has warmed up a little? meaning is the tapping louder when the engine is cold or the same no matter cold/hot.

Is the oil getting up there? remove the inspection cover with the engine running (should make a nice mess everywhere).

Mezo.

[zigzag]

hi there mezo from cold it is sometimes there but not always , it seems to be worse as the engine is warming up say the first 5 miles . when it is fully warm it is still there but i think not as distinct . it is a bit puzzling the bike does not smoke or use oil . but it defenatly was not there in the first three years of me having the bike . dont get me wrong its not like a jackhammer , just not right . its more promanant on the right side of the bike as you sit on it, and does seem to come from the ex valve area . sorry for the poor description . cheers for the reply. zigzag. ps i will remove the tappet covers one by one with engine running but that will have to be later on in the week

[wetcoastrider]

I'm guessing it's your valve tappets. They do go out over time and need to be adjusted. Check your manual for the intake and exhaust valve clearances , get a feeler guage and adjust as necessary.
Post a video with sound it may help diagnosis.

[mudandsmoke]

I am not a Yamaha expert, but if the valves have been run for any length of time with excessive clearance, then the tappet will hammer it's way into the top of the valve stem making it impossible as you state to accurately set the clearances. I would guess that the Yamaha engine uses a common rocker to open both valves, the easy way to check the problem is to set the tappets to very nearly zero clearance by releasing the locknut and screwing the tappet until it makes contact with the valve and then back off say an eighth of a turn and lock the nut. do the same for both exhaust valves. There would be no harm done if you set them to zero, but only run the engine for a few minutes, just to test. It may of course not be the exhaust valve, could be the inlet valves or even piston slap or cam wear. Short journeys are an engines worst enemy regarding premature wear.
Andy

[zigzag]

hi guys and thanks for the replys , ive not used the bike since my last post if the weather is better at the weekend i will investigate a little more . i think the first job is to remove the ex tappet screws and inspect them , then reset etc . i will post anything i find . again thanks for the input. zigzag