grinding sound

GoldenMotor.com

chrome

Member
Jan 10, 2010
88
0
6
manila, philippines
Hello Norm I hope you could help me with my 2 stroke motor problem... Since I got it to start, and it's been running for about 10 kilometers only, there's a grinding sound coming from the motor. It's so loud it even drowns out the sound of the muffler. Is there anything that needs to be greased in the motor? Thanks in advance!
 

BarelyAWake

New Member
Jul 21, 2009
7,194
21
0
Maine
These lil 2 smokers are known for excessive clutch noise, odds are what you hear is perfectly "normal" - you can reduce the noise somewhat by applying a small amount of grease to the gears under the clutch cover, no more than say a pencil eraser sized gob as you don't want excess grease getting into the clutch itself. There is also the small push rod & bearing that's part of the clutch actuator - another lil gob o'grease in there would help it out.

Still - it'll be loud even after that's done, I sprayed a coupla coats of rubberized undercoating on the inside of just the cover and that alone cut the noise down considerably. They also sell covers such as these: JNM Damp-Pro - despite alla "fancy talk" they're essentially doing the same thing as stickin' a mouse pad to the cover which others have done successfully to help mute the noise ;)
 

chrome

Member
Jan 10, 2010
88
0
6
manila, philippines
Thank you so much for keeping my hopes up that the sound is "normal". I'll surely do your helpful suggestions which also gave me an idea; is it ok to drill some holes on the clutch cover and then put a sound deadening pad on the outside of the cover just to give the noise a little more space to escape and let the pad absorb it? Thank you for the suggestions and the quick response BarelyAwake!
 

bairdco

a guy who makes cool bikes
Aug 18, 2009
6,537
264
63
living the dream in southern california
i wouldn't drill any holes in it. what i did was:

at Ace Hardware they sell a pack of gasket material. it's 3 squares, one red rubber, one cork, and one grey stuff (you can use the grey to make intake and base gaskets.)

i used the red rubber one, traced out the clutch cover, and cut it to fit inside. i used clear spray paint as the glue. just spray a bunch on the inside of the cover, let it sit a few minutes to get tacky, then stick the gasket inside. i left mine overnight with a can sitting on it to weigh it down.

still working after a month. the spray paint works great.

if you want to be sure that's where the noise is coming from, just stick your hand over it while the motor's running, and see if it quiets it down.
 

chrome

Member
Jan 10, 2010
88
0
6
manila, philippines
i wouldn't drill any holes in it. what i did was:

at Ace Hardware they sell a pack of gasket material. it's 3 squares, one red rubber, one cork, and one grey stuff (you can use the grey to make intake and base gaskets.)

i used the red rubber one, traced out the clutch cover, and cut it to fit inside. i used clear spray paint as the glue. just spray a bunch on the inside of the cover, let it sit a few minutes to get tacky, then stick the gasket inside. i left mine overnight with a can sitting on it to weigh it down.

still working after a month. the spray paint works great.

if you want to be sure that's where the noise is coming from, just stick your hand over it while the motor's running, and see if it quiets it down.
@Bairdco - Thanks for the input bro! Next stop, Ace Hardware! pino.
 

BarelyAWake

New Member
Jul 21, 2009
7,194
21
0
Maine
NP chrome, I remember very clearly wondering if my first engine was going to immediately tear itself to pieces given the horrible sounds it was makin' - thousands of miles later, it's still makin' 'em. Yet there's no perceivable wear and other than a periodic re-application of grease I've not had to do any repairs... so "normal" it is lol :p
 

chrome

Member
Jan 10, 2010
88
0
6
manila, philippines
NP chrome, I remember very clearly wondering if my first engine was going to immediately tear itself to pieces given the horrible sounds it was makin' - thousands of miles later, it's still makin' 'em. Yet there's no perceivable wear and other than a periodic re-application of grease I've not had to do any repairs... so "normal" it is lol :p
I actually haven't found time to apply grease or any of the suggestions by all you good guys here...but my ride seems to be running better and smoother...this weekend, will try to open the cover... hopefully, if the grinding sound stays, my engine lasts for thousands of miles too! I'm so loving this hobby, I went and bought another pocket bike as a projectpino.
 

Bombardier

New Member
Feb 3, 2010
17
0
0
australia
I found with my cheapo 50 cc made from left over parts the lock screw and clutch flower nut rub on inside of the aluminium side cover when you pull the clutch in making a grinding sound and it leaves alluminium filings inside the side cover .so i had to put 2 gaskets on the side cover to give the disengaging clutch room not to touch the side cover . take your side cover off and if there is a round wear mark on the inside or silver coloured fillings there then you know what was causing the grinding sound now.
 

chrome

Member
Jan 10, 2010
88
0
6
manila, philippines
I found with my cheapo 50 cc made from left over parts the lock screw and clutch flower nut rub on inside of the aluminium side cover when you pull the clutch in making a grinding sound and it leaves alluminium filings inside the side cover .so i had to put 2 gaskets on the side cover to give the disengaging clutch room not to touch the side cover . take your side cover off and if there is a round wear mark on the inside or silver coloured fillings there then you know what was causing the grinding sound now.
Your timing is perfect Bombardier! it's good to know what else I might find in there even before I actually "go in". Thanks for the input mate!pino.
 

Technocyclist

Motorized Bicycle Senior Technologist
Jul 7, 2008
462
0
0
Asia
It could be the flower nut, but for me I tightened the nut then adjusted the clutch cable instead. You may also wanna check the ball bearings inside, those bearings usually require some lubrication also.