another little problem

[kemp2368]

hi all again
i have another small niggle with the bike
its i have a small backfire/pop when i close the throttle,it does not happen all the time just now again,say 1/2 on a 10mile trip.
i can live with it at the moment but i am a bit of a fiddler and hoping someone has got any ideas
also i think the tappets sound a bit noisy,i no its a 31 year old bike ,and i do expect a few little niggles ,but i am a fussy git,should i expect them to be a bit noisy?? as it has done 37000 miles
but she starts and runs really well,ticks over once warm nice and smooth,just a bit noisy on the tappet side,and the little pop/backfire
the bloke i got her from only did 200miles on her in 2 years so would it be that she just needs a few hundred miles put on her to free everything(i am using her most days to and from work but thats only 3 miles each way)

[florence]

If the backfire is on the over-run it is most probably caused by a leaking joint between one of your downtubes and the cylinder head.  My bike does it a lot but it is accentuated by the rather short exhaust.  I quite like it.  I have found that it can be reduced by slower throttling off.

The tappet noise I cannot comment upon without hearing it.  Chances are, if it's not massively loud, it's most likey to be normal.  All the Honda engines I've known, both new and old are rather rattly, especially the clutch on these fours.

[kemp2368]

If the backfire is on the over-run it is most probably caused by a leaking joint between one of your downtubes and the cylinder head.  My bike does it a lot but it is accentuated by the rather short exhaust.  I quite like it.  I have found that it can be reduced by slower throttling off.

The tappet noise I cannot comment upon without hearing it.  Chances are, if it's not massively loud, it's most likey to be normal.  All the Honda engines I've known, both new and old are rather rattly, especially the clutch on these fours.

hi there,yes it is on the over-run,as for the downtube,do you mean the exhaust as i have noticed a snapped off exhaust stud to the cylinder head

[florence]

Yep, that will be it.  When you are on the over-run it will be sucking in air into the exhaust and causing the hot gases to ignite.  If you can replace the stud and get it to seal the problem will go away.

[kemp2368]

thanks for that