Engine is slight knock kinda loud. feels like it builds up to power band let me know I'll post videos
Engine knock
- Thread starter gwatt5
- Start date
If its a detonation issue, make sure you got the right fuel mix, in the tank , if you are running the block off for oil injection.
and make sure your carb jet is right, compared to if you are running a after market exhaust.
stock main, 230, number seen on the main jet, when you remove the float bowl.
a after market pipe and silencer or a jigh performance air filter, would require a bigger size jet.
If you check or correct those areas, and the knock does not go away.
it could be maybe the following. loose flywheel, loose clutch. shear pin about to break.
or a rod bearing going out, or a piston that is cracked and about to break.
Lets hope its one of those other easier issues to correct.
and make sure your carb jet is right, compared to if you are running a after market exhaust.
stock main, 230, number seen on the main jet, when you remove the float bowl.
a after market pipe and silencer or a jigh performance air filter, would require a bigger size jet.
If you check or correct those areas, and the knock does not go away.
it could be maybe the following. loose flywheel, loose clutch. shear pin about to break.
or a rod bearing going out, or a piston that is cracked and about to break.
Lets hope its one of those other easier issues to correct.
It's most likely to be just plain old piston slap from a worn bore. How many hours on this top end?
the top end is like 2 months old has the right jetting and doesnt have block off kit
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2 months old and you can push it down like that?
I'd say it's worth the top end gasket set to pull that back apart and check it out. It sounds like pistons slap to me.....
I'd say it's worth the top end gasket set to pull that back apart and check it out. It sounds like pistons slap to me.....
You won't know until you pull it down and measure the piston to cylinder clearance and cylinder taper/out of round. Once you know if it's ok, you know where to go from there.
I played the video like 5 times, over and over, Thats not a knock at all.
That is chatter. And wow, the finger push the kicker down, wow !
How was the top end re done two months ago.
who has it bored out ? or was it just honed and re ringed ?
Now, that info would be a plus.
Cuz if it was done right just two months ago, and its that bad already. You might have a bad crank or rod, with to much slop, causing that much wear / slop on the piston / rings.
Or is was broken wrong and running lean, to have that kind of wear in two months.
That is chatter. And wow, the finger push the kicker down, wow !
How was the top end re done two months ago.
who has it bored out ? or was it just honed and re ringed ?
Now, that info would be a plus.
Cuz if it was done right just two months ago, and its that bad already. You might have a bad crank or rod, with to much slop, causing that much wear / slop on the piston / rings.
Or is was broken wrong and running lean, to have that kind of wear in two months.
okay im new at this i usually just figure it out but im stuck honestly and i couldnt firgure out how to post new threads so forgive me if i interupt i have had many atvs and this is my 1 2 stroke atv a 2001 yamaha blaster i just rebuilt the whole atv i have plenty of spark and fuel, brand new reeds but for some reason the only way this will run is if i pop start it when i kick start it i just waist my time now i put a new top end on it and it has only 90 psi i dont get it someone help please
No leak test after rebuild did proper Break in and I had it honed bored and did piston and rings
Mine sounds just like that,been wonderin,thinkin piston slap,no clue to age and passes leakdown test, i still ride it like hell thougj,but i have compression,cant push it over by hand like that,Waitin to get some cash up n do a total rebuild with my spare bottom end.I am curiouse what u find at teardown.
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