I have very little hands-on knowledge of how my motorcycle engine works, please don't fault me. But recently, after getting a main gasket replaced about a month ago (large one between the 2 main blocks of the engine where I was having a gas leak), I've been experiencing way lower mileage out of my fuel, and also getting backfires almost every time I accelerate and then back off after awhile. SOmetimes they're quite loud and give other people a fright, especially given the current context of the times in the country. I also notice that in general my exhaust does have a bit of fuel or partially combusted fuel smell to it now, so something is not mixing or combusting properly. I want to be armed with a little more info when I go in to have it looked at and see what repairs I need done.

Anybody got some tips about probable causes here ? Is there enough info in my post to make educated guesses ? Is having the mechanic take it for a spin and telling him what I see enough to diagnose ?

Thanks for any help here, guys.

also change your oil because it sounds as if you may have fuel in the oil.

<deleted>???

Check you timing chain. it will have been removed and if they didn't set Top Dead Centre correctly it could result in the syptoms you post. Also have your valve clearances checked. But 5 'll get you ten its the timing chain.

Before they check that, there is an outside chance its the CDI unit. this plugs in and plugs out easily so try it with one from another bike the same as yours first. if that cures it, you just need a new black box. Not expensive. But more likely its the chain...

<deleted>???

Check you timing chain. it will have been removed and if they didn't set Top Dead Centre correctly it could result in the syptoms you post. Also have your valve clearances checked. But 5 'll get you ten its the timing chain.

Before they check that, there is an outside chance its the CDI unit. this plugs in and plugs out easily so try it with one from another bike the same as yours first. if that cures it, you just need a new black box. Not expensive. But more likely its the chain...

Agree with Loz on this one, assuming the problem has appeared after the head gasket replacement.

May also have been caused by incorrect torque settings replacing the head, but would expect the timing chain is 1 link off.

Thanks for this info guys. But I am remedial with motors so I have to ask a bit more here. Like where am I gonna find the cdi unit ? And Loz, your idea is to borrow the connector wire off a friend n see if that changes things ? And if so, then go pick up a new one ?

Otherwise, when I take it in, I'll have my sparkplug checked (crap,... so embarrassing: I've got one or two down there ? I"ll go take a look in a minute.)

Also wishing I had the vocab in Thai to describe all of this stuff. I am more or less fluent but have almost zero engine or mechanics vocabulary.

If you guys know what you call the timing chain or anything else in THai, please clue me in on that too. Otherwise I'll post over to the language forum probably.

But thanks to all anyway. I'm having a busy week but not driving much. I definitely want to nail down the health problems of my bike and have it running with efficiency within the next 7 days.