popping noise out of front end of engine....

GoldenMotor.com

Legwon

Member
Mar 2, 2013
248
0
16
Van bc Canada
?????

as I read it, the gasket is fixed & the bike is starting & running fine now with just an idle problem left

did I miss a post somewhere?
yes and no.
tightened up the exhaust, the popping is gone. but the exhaust gasket is pretty well blown apart :( .. just enough so that it actually works.
gonna pick up some gasket material today.

yes i will be lapping the head this weekend. hopefully that will turn things around for me... been one headache after another with this .. although not half as bad as the original i had 6-8 yrs ago.. lol

:-||

ps.. there needs to be a sledgehammer icon..lol
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,837
252
63
up north now
good news and bad ...

start fine now that tighten up exhaust and put wire on it ...gasket almost blown apart :s

but idle still out ...Im assuming that has to do with the fuel mix change since break in ?

By this post, I would guess the thing is still not running right, but adjusting the float or C clip won't help and idle problem.
 

Toadmund

New Member
Jan 19, 2012
792
6
0
Saint John, New Brunswick, Canada
Always a good idea to do any lapping or mods BEFORE the motor is installed on the bike.
A lesson learned the hard way, the best way to learn. (wax on, wax off / motor off, motor on)

I absorb info from forum like sponge, knew what must do, porting, lapping, whatever, then motor go on bike.

Except the piston skirt notch and needle bearing spacer retainers, removed motor from bike as it was stuff I intended to do later.
 

maniac57

Old, Fat, and still faster than you
Oct 8, 2011
4,484
22
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memphis Tn
that sounds like the root of your problem then - the muffler is way too heavy to hang from just two little studs

get a piece of coat hanger wire and wrap it around the output pipe of your muffler, then wrap the other end around your frame and back down to the muffler again - then put a screwdriver between the two parts connecting the muffler to the frame & twist them until the muffler is pulled up tight
If you do this you are likely to break the exhaust studs or bend them so badly they don't seal. Please do it some other way.
 

Kioshk

Active Member
Oct 21, 2012
1,152
10
38
Connecticut
yes and no.
tightened up the exhaust, the popping is gone. but the exhaust gasket is pretty well blown apart :( .. just enough so that it actually works.
gonna pick up some gasket material today.

yes i will be lapping the head this weekend. hopefully that will turn things around for me... been one headache after another with this .. although not half as bad as the original i had 6-8 yrs ago.. lol

:-||

ps.. there needs to be a sledgehammer icon..lol
You'd be better off with NO exhaust-gasket than a defective one; I suggest you remove it until you get the material.
 

Legwon

Member
Mar 2, 2013
248
0
16
Van bc Canada
You'd be better off with NO exhaust-gasket than a defective one; I suggest you remove it until you get the material.
this is true ONLY if the bolts ur using tighten all the way to manifold. the ones i was using at the time didn't. they only had half threads.
have replaced the gasket and new Allen key bolts... solid as a rock now ;)

waiting for weekend now to lap the head
 

Kioshk

Active Member
Oct 21, 2012
1,152
10
38
Connecticut
Wait, what?
Simple: better to have a metal-to-metal leaky seal than to have a gasket with a hole in it. When those thick exhaust gaskets go, they leave pretty big, loud, and unidirectional hot-gas jets.

Did this the last time my gasket went. And while I awaited a replacement, I used this stuff very effectively ($6 a sheet @ NAPA):
 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
While you're lapping the head take a few minutes and do the same to the exhaust manifold flange. It's rare to find one that is absolutely flat and fits flush to the cylinder. The welding process usually warps the flange. It can be sanded or ground flat using the same method as lapping the head. I use a bench mounted belt sander but it can be done by hand too, just a little more work.

Tom
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,837
252
63
up north now
Simple: better to have a metal-to-metal leaky seal than to have a gasket with a hole in it. When those thick exhaust gaskets go, they leave pretty big, loud, and unidirectional hot-gas jets.

Did this the last time my gasket went. And while I awaited a replacement, I used this stuff very effectively ($6 a sheet @ NAPA):

A leaking exhaust is a leaking exhaust.

What is a bunch of "little" leaks add up to one moderate leak?
At any rate a small exhaust leak is an annoyance, nothing more.
 

Legwon

Member
Mar 2, 2013
248
0
16
Van bc Canada
While you're lapping the head take a few minutes and do the same to the exhaust manifold flange. It's rare to find one that is absolutely flat and fits flush to the cylinder. The welding process usually warps the flange. It can be sanded or ground flat using the same method as lapping the head. I use a bench mounted belt sander but it can be done by hand too, just a little more work.

Tom
already done to the exhaust and the intake with a straight edge and Dremel , when i ported them. :)
 

Legwon

Member
Mar 2, 2013
248
0
16
Van bc Canada
will be continuing with this later this week(i hope) once my new top end arrives.
i didnt get around to lapping the head that weekend, and i most likely should have. top end blew up, and jammed the bottom end :s .. on tues last week. vendor is supplying new parts.
the FIRST thing i will be doin is lapping the head & cylinder.
also getting a new clutch assembly and gear tool for my older motor, so i will be disassembing the bottom end of this one, to remove the debris and check for damaged parts.
any suggestions as to what i should be looking for when i do?
 
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Jumpa

New Member
Aug 12, 2011
607
2
0
Cape Cod
i HAVE ONE FOR YOU GUYS i JUST BOUGHT MY 3RD MOTOR damn caps well got it all set up chain on before adding fuel .
I always take them for a pedal ride around the block well just as I started to go I hear this clicking noise like every 2nd revolution it seems It isn't the piston it isn't the chain, I know this bc I took out the plug to make sure the piston wasn't moving and it wasn't moving with clutch in yet I still get this clunking noise.

It's not even a click, it sounds like I'm tapping the case with a ballpeen hammer it does it in reverse also any idea's? I removed the bucking bar 3 screw cover then put it back on, & it stopped so i started the break in after the first easy ride I noticed the clunking is back when the motor is idle no noise at all just as soon as I start rolling it clunk clunk clunk .. I got a clunker!! what could it be?
 
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maniac57

Old, Fat, and still faster than you
Oct 8, 2011
4,484
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memphis Tn
Using a master link? They are usually a bit wider and can hit inside the cover. Did the sprocket cover have marks? Check it out.
 

Jumpa

New Member
Aug 12, 2011
607
2
0
Cape Cod
I did check it out . I even found that actuator arm cover thread 2 door made "thanks 2 doors" so I thought I was in fat city. So i dremeled it put it back together and i had the same issue still clunk clunk. I feel nothing when I touch the chain with my hand "vibration usually follows however when I put my finger on the flower nut I can feel an intense clunk it does it about every 4 chain links when rolling he wheel
 

crassius

Well-Known Member
Sep 30, 2012
4,032
158
63
USA
take the drive cover off again, remove the spark plug and watch the chain as you roll the bike - you may have some teeth on that sprocket that are a bit too fat for the chain, causing it to rise up and hit the engine until that knocks it back down

if so, file or grind the teeth a bit
 

maniac57

Old, Fat, and still faster than you
Oct 8, 2011
4,484
22
0
memphis Tn
Next thing to check would be the gears on the crank and clutch. Pull the cover and check out the gear teeth, a small bit of debris caught in the gear teeth can cause what you describe
 

Jumpa

New Member
Aug 12, 2011
607
2
0
Cape Cod
take the drive cover off again, remove the spark plug and watch the chain as you roll the bike - you may have some teeth on that sprocket that are a bit too fat for the chain, causing it to rise up and hit the engine until that knocks it back down

if so, file or grind the teeth a bit
No noise when the cover is off however I don't think it is the cover I think it stops because the pressure is off the bucking bar today I'm going to put the cover on without the actuator arm this will eliminate the cover/chain all together at least I hope Did I mention it looks as if the front gear "the little one" looks as if it has pushed outward a 1/2 "
 

Jumpa

New Member
Aug 12, 2011
607
2
0
Cape Cod
well i did it and no noise with the actuator arm out and the cover on with the plug out then I put the arm back in bolt cover on plug still out noise clunk clunk clunk , nothing is touching the arm I eliminated that possibility as well