weird noise, rings catching exhaust port..

just like superman, swoop down and save us lois lanes of the blaster world !!!!!!
and "call me, i'll be in the shop all day" on a sunday!!!!! < unheard of, but awsome!!!!
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Very strange sound but definitely ring / piston / port related. First I'll address some of the concerns.
1.Pistons are not straight. The top ( where the rings go ) is smaller in diameter than the bottom skirt. The largest part of the piston is an area about 1/2” above where the skirt ends and at 90 degrees to the wrist pin. This is the area to be measured when calculating piston / bore clearance. This will always be the first area of the piston that starts to show signs of being worn.
2.Evidence of the hone pattern only being visible on the bottom sides of the cylinder is normal.
Make sure the rings are in the correct way. I'm assuming you run a Wiseco piston. The rings will be marked on one side. The mark faces up. It doesn't matter where you put them ( top or bottom groove ) if everything is new but never switch the position after the engine has been run. Lay the rings on a flat surface and make sure they're still flat and not distorted. Check the ring end gap. It should be at least .011. Just push the ring into the top of the bore about an inch and check with a feeler gage. The ring has to be parallel to the top of the bore to get an accurate measurement. Check the clearance between the ring and the ring groove in the piston. Anything over .002 is bad. You can also measure the width of the ring but you'll need a set of dial calipers. You should find no variation in the width. If you do, note where the ring gets smaller in relationship to the cylinder. Pay particular attention to the thickness of the ring in relationship to the exhaust port. Check the piston / cylinder clearance. This cane be done with a feeler gage if you don't own a bore gage. With the piston and cylinder off the engine, slide the piston ( take the rings off) into the bottom of the cylinder. Slide a feeler gage between the cylinder and the bottom part on the skirt @ 90 degrees to the pin. DON'T FORCE IT!!!! Start with a .001 and work your way up .001 at a time. If a .002 wont go between the piston and the cylinder, you need more clearance. If a .005 goes in, time of a new bore. I typically run .0025 - .004 depending on what I'm doing with a certain engine. Don't even think about re-using the C clip. Check the ring locating pins in the back of piston, if you can move them or take them out, the piston is junk. Take a good look at the chamfers on the ports, they should be nice and round. Pay particular attention to the exhaust port. If you have a loop or magnifying glass, examine the face of the rings. Look for any burrs. This should help but if after all this you don't find anything, give me a call. I'll be in the shop all day. 860-230-5003

Ken

thanks alot ken, im kinda at a stand still as far as what to do now.. i think im going to take it to the guy that built the motor thursday on my day off and see if he thinks i got a crap bore job. if so im thinking the only safe thing to do is box it up and send it out to ya, i have zero tools for measuring stuff like that.. thanks for taking the time for that writeup man, i appreciate it and i will keep in touch on this.
 
during my quick search for a superman to put kens head on, i came across this, and since this thread is now over, and noobs has the solution to all his troubles, i figured everyone could use a little "superwoman" too.................
35d0paw.jpg
 
during my quick search for a superman to put kens head on, i came across this, and since this thread is now over, and noobs has the solution to all his troubles, i figured everyone could use a little "superwoman" too.................
35d0paw.jpg

Hubba hubba hubbba! BOING!I:I
 
ok small update.. upon further inspection there seems to be faint scuffing on the intake/exhaust sides of the cylinder (you cant feel them, very minor) so im guessing it must of got a bit hot at one time.. wich REALLY gets to me because i take care of this bike good.. airleak checks, plug chops, regular plug checking make sure eveything is good and snug before every ride and this still happens X( feels like a big old slap across the face.. so once thursday comes along i will take it to my guy and see what he has to offer.. if it needs a bore definately not going with the last guy.. also i dont belive this has been catching for any longer than last tuesday, i remember putting it together originally and spinning it over and not hearing the noise and there is no chance i wouldnt have noticed. thanks to those who have chimed in to help -noob
 
Gee Noob, I would think slight scuffing in those areas to be normal wear. Hope it checks out well.

^^^yeah noob thats normal wear, dont worrie about that unless the cylinder walls are scratched up or scored, then you need a bore to clean it up. take a picture if you can get a good one so i can take a peek, you may be able to just do a nice hone and new rings and get away with it. do you remember leaning this topend out in the break in at all?? my cylinder wall was pretty scary (to me) i was told to just do new rings, been fine ever since
 
noob..if you need me to check it out just send it out to my address ..ill measure it out and see what conditon the bore is in and let you know
 
noob..if you need me to check it out just send it out to my address ..ill measure it out and see what conditon the bore is in and let you know

thanks for the offer dude, i think what im going to do is take it to the shop thursday and make sure it just dosent need rings and a hone. if he says its more than that i will get in touch with ya.
 
noob..if you need me to check it out just send it out to my address ..ill measure it out and see what conditon the bore is in and let you know

Awesome offer! That's why this site is the shizznit!I:I


Noob I hope it's nothing serious bro, i will be staying tuned!
 
ok found it, its my tranny gear behind the basket. why it only makes the "tink" when the crank is in the bottomed out position is beyond me.. mabey a tweeked gear tooth making the other gear move a little? so is that gear supposed to be no movement tight? is that a possible bad bearing of some sorts? lets hear those opinions guys.

 
did you bend up the washer on that gear? i cant see. thats your counter balancer gear, make sure that nut on the gear is tight and its not backing off slowly.
 
hmm I was going to see if your pistion ring locating pin fell out... the noise might have been the piston ring rotating and catching on the port... But good thing you found it idk what to do
 
possibly a worn counterbalancer bearing??....or the counter balancer end hitting the inside of the case?????, there is a tiny bit of room on the inside of the case where the end sits, not sure man
 
possibly a worn counterbalancer bearing??....or the counter balancer end hitting the inside of the case?????, there is a tiny bit of room on the inside of the case where the end sits, not sure man

im thinking thats what it is man... i can wiggle the gear and the whole thing moves a little.. at least the cases were split like 4 months ago
 
i noticed when I pulled my tranny apart last time that the rivets that hold that gear together had a little play in them. every thing seems ok i just figured that was normal
 
That's weird, At first I'm thinking the same a freek, maybe a bearing going bad and it's rubbin the case a hair? A few other things I can think of - your clutch basket inner nut is coming loose or the the gear on the back of the basket (the small one that exploded on me when my spring from the kicker popped out of it's hole) maybe coming off or loose or cocked? Take the clutch basket off and spin the crank, still happening? If so that leaves out any issues with the basket. My next step would be to slowly rotate the crank with the basket off and listen again, try to pinpoint exactly. If I couldn't figure it out, It would be going to Ken!