jclee71
Member
Have two identical Venoms, both run great, but one of them while idling it makes loud almost knocking noises intermittently, almost sounds like it could be detonation, or maybe a spark jumping wires, I have no idea what to do, it runs great but I’m just worried something internally might be ready to let loose or something, anyone have any idea?
Check the two front motor mounts. Common on Vipers to break.
Make sure brackets aren’t broke, and bolts haven’t backed out.
Make sure brackets aren’t broke, and bolts haven’t backed out.
A couple of bucks
VIP Member
There has been a rash of cracked exhaust manifolds on here this season.
Edit: those were Viper not Venom manifolds.
Edit: those were Viper not Venom manifolds.
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Is there a ring gear on the clutch?
all good things to check.
my thoughts are to wrist pin/piston slap if all above are good.
my thoughts are to wrist pin/piston slap if all above are good.
jclee71
Member
It it electric start, is that what you mean by ring gear, also would a compression test of each cylinder disgnose piston slap, bought sled used and took it on few trips and seems to run fine, think I check compression when I bought and it was very good
Yes, sometimes the gear on the backside of clutch sheave comes loose and it makes some noise when this happens.
on these sleds the ring gear for the starter is bolted to the back of the primary clutch. they are notorious for the bolts coming loose and making a knocking sound. how to check it is to either look down the back side next to the engine and see if anything is shiny looking. the other way is to hold the clutch still and grab the gear and see if it moves independant of the clutch. had to replace 2 clutches on my dads 05 sx venture because of this gear coming loose in under 8500 km. i think i have it fixed now but not done testing yet.
cannot diagnose piston slap with compression tester. motor needs to be torn down for that.
here is a pic of the back of the primary clutch with the ring gear installed in this thread.
https://totallyamaha.net/showthread.php/105139-Sx-chassis-e-start-mod
cannot diagnose piston slap with compression tester. motor needs to be torn down for that.
here is a pic of the back of the primary clutch with the ring gear installed in this thread.
https://totallyamaha.net/showthread.php/105139-Sx-chassis-e-start-mod