Is this normal - CG125 - VIDEO

[heytc]

Hi I'd appreciate you having a look at this video to see what you think - Honda CG125. Sorry about the quality of the video -

video

I had a sudden loss of compression while I was trying to get the bike working a couple of weeks ago. Here's the thread -

here

I've replaced and lapped the valves. I've checked the piston rings and they seem fine and so does the barrel.

After investigating a while it seemed like the compression was being lost from the cylinder head gasket.

So I've lapped the surfaces with grinding paste and used Hylomar and it doens't seem to be losing a lot of compression from their anymore - in fact I'm not sure its losing compression at all. The compression has gone up to about 120/130, sometimes 150.

There's a strange popping sound coming from the exhaust valve - like its opening where there's a vacuum. You can hear it on the video. The kickstart isn't very smooth as you can see from the video. Sometimes it doesn't seem to push properly. Well I dont know if any of this is normal or not...

The exhaust and the inlet manifold aren't on the machine at the moment if that makes a difference.

Thanks ever so for looking

[----]

The popping sounds like the compression escaping out of the exhaust as it should with no exhaust on Sounds normal.

The kickstart will go a little limp (get half way through the kick before you regain pressure) because there's no compression when the piston is going down.
You should press the kickstart down until you feel lots of resistance (compression) then let it back up all the way,then kick it.
This ensures you're kicking it over on the compression stroke.
I think i've explained that right
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DRZ-400sm

[heytc]

Thanks Truxx. Thanks for the reply. I've put the exhaust back on and it's stopped most of the popping. Well its become more of a gulping when the valve opens. Still doesn't sound too healthy.

You've helped my kickstart technique with your expanation

[temeluchus]

That sounds normal for a motor with the exhaust off.

youll get sucking noises from the inlet and that "blorp" noise from the exhaust.
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Some shite cruiser. Now with guns and FREEDOM!