engine tick what is this?

[KartFab]

So i took out the 'bronda' mini bike over the weekend. Starts just fine, but it seems to have this little tick to it when running. I dont notice any problems with acceleration or anything like that either.

Im no expert on engine sounds, this could be normal, but what in the world could be causing this tick tick tick sound? Engine seems to be running fine, and its making me worried. It has this little tick tick tick sound at low & idle rpms.

Last year my daughter was riding it through a giant mud puddle and layed it over on its side. Since then it has put out a bit of smoke. on accelleration only at low rpms. I always thought it was just very rich, and it has some carbon buildup in the head but man, i hope I dont find any problems when i open it up.

Any thoughts and ideas before i crack it open?

My worst nightmare would be
scored cylinder wall
valve guides wallowed out.

Again, what could be this tick tick tick sound? Normal valve-train noise?

 

[SammyCat]

It might be piston slap.

 

[bob58o]

Does it sound like this ticking?
Maybe at about 2 minute in.
I'm trying to diagnose my own ticking as well.
I was guessing valve train, but I don't really know for sure.
https://www.youtube.com/watch?v=c3ishxIHL90&t=135s

 

[ezcome-ezgo]

Pull the valve cover and check the clearances. That's pretty straightforward. Or GAB.

 

[bob58o]

I've heard you can stick the fat end of a screwdriver in your ear and use the tip like a stethoscope. Touch it to the valve cover, touch it to the block,... Ticks get louder when your screwdriver tip gets close.

 

[itsid]

a stethoscope costs like ten bucks, one with a feeler needle a buck more,
but a long screwdriver works, as long as you keep a safe distance between your hair/clothing and all rotating parts of course

Anyways,
I'd remove the clutch first to see if it's it's bushing that created the play which resulted in that ticking sounds.

Once that's out of the way, I'd check that nothing has cought in the air vents of the shroud (knocking against the flywheel;
then check the magneto being still fixed correctly, and then work my way in.
(valves, cam, crank, conrod...)

But flywheel and dirt... I think you see why I suspect it to be an "outside of crankcase" issue

'sid

 

[Hellion]

Mechanic's stethoscope. Horror Fright has 'em, of decent quality and I happen to have one.

Forgot all about it--they're neat to use though.

 

[KartFab]

I did some more reading into this and rotating things cause like a buzz, whir, or whining sound, and reciporicating things cause ticks.

I will report back. Yes that sounds like the problem, but mine is more distinct. Not even sure if it is a problem though ehhh we shall see. we shall see.

Also, on a side note, oct 8th is a mini bike race and show out of the ft. worth stockyards. Im going wooohooo!

Mini Bike Race and Show
Public · Hosted by Rat Rod National Build Off and Go Power Sports

Sunday, October 8 at 3 PM - 9 PM

Billy Bobs Fort Worth Stockyards
2520 Rodeo Plaza, Fort Worth, Texas 76164

Details
$10 entry fee or one new unwraped toy. Trophie for fastest bike.
Will be located just east of the Barbeque place north of Billy Bob's

 

[Texan]

I did some more reading into this and rotating things cause like a buzz, whir, or whining sound, and reciporicating things cause ticks.

I will report back. Yes that sounds like the problem, but mine is more distinct. Not even sure if it is a problem though ehhh we shall see. we shall see.

Also, on a side note, oct 8th is a mini bike race and show out of the ft. worth stockyards. Im going wooohooo!

Mini Bike Race and Show
Public · Hosted by Rat Rod National Build Off and Go Power Sports

Sunday, October 8 at 3 PM - 9 PM

Billy Bobs Fort Worth Stockyards
2520 Rodeo Plaza, Fort Worth, Texas 76164

Details
$10 entry fee or one new unwraped toy. Trophie for fastest bike.
Will be located just east of the Barbeque place north of Billy Bob's

Dang! Was planning to go up to DFW that weekend for the State Fair and Cowboys vs the evil Packers....too bad game starts at 3pm also. May still make it afterwards.

 

[KartFab]

Clearances were good. Valve guides were shot. Valves rocking in the guides. Now im going to go about replacing the guides.

 

[bob58o]

Clearances were good. Valve guides were shot. Valves rocking in the guides. Now im going to go about replacing the guides.

Let us know if that cures the tic.
Also let us know if that doesn't cure the tic.

 

[Randy H]

Tic or Tick?

 

[bob58o]

Or a Tac?

This thread reminds me of an Edgar Allan Poe Poem. Not sure yet if the Raven, or Tell Tale Heart.

 

[KartFab]

so just to let you all know what was causing the tick:

1) not the valves, even though they were very loose in the guides.

2) THE PISTON was shot, skirt had a lot of marring and was rocking back and forth in the block. Had to toss the piston, and ended up getting a decent dual bearing block for $40 and put all the goodies in that instead.

 

[landuse]

so just to let you all know what was causing the tick:

1) not the valves, even though they were very loose in the guides.

2) THE PISTON was shot, skirt had a lot of marring and was rocking back and forth in the block. Had to toss the piston, and ended up getting a decent dual bearing block for $40 and put all the goodies in that instead.

Thanks for the update