Author Topic: cylinder goop  (Read 203 times)

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Offline Don R

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cylinder goop
« on: March 11, 2025, 10:54:26 AM »
 yuk. This is what the fins collect.
No matter how many times you paint over a shadow, it's still there.
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Offline bryanj

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Re: cylinder goop
« Reply #1 on: March 11, 2025, 12:07:39 PM »
That is external sh1te heated up
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Offline BenelliSEI

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Re: cylinder goop
« Reply #2 on: March 11, 2025, 12:56:49 PM »
……It’s amazing what you can find in there!

Online M 750K6

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Re: cylinder goop
« Reply #3 on: March 15, 2025, 03:18:00 PM »
Looks like my wife's rice pudding  :)

Offline Don R

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Re: cylinder goop
« Reply #4 on: March 15, 2025, 03:26:00 PM »
 55 years of oil, dust and bugs, it seems weird that there's an engine passage open to air except for the gasket.
No matter how many times you paint over a shadow, it's still there.
 CEO at the no kill motorcycle shop.
 You don't need a weatherman to know which way the wind blows.

Offline HondaMan

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Re: cylinder goop
« Reply #5 on: March 15, 2025, 07:07:59 PM »
That's raw crude!
:)
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Offline PeWe

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Re: cylinder goop
« Reply #6 on: March 16, 2025, 12:13:56 AM »
I did not trust trust the base gasket to stop sand and dirt from come inside when taking off the cylinder.

I plugged the holes with JB Weld, ca 8-10mm thick. 2k clay wariant as a bottom, filled up with 2k epoxy. Drilled a few small holes in the aluminium to give it more grip.
I could have made the JB Weld epoxy thicker to improve the stability. 25mm or more.

The big sleeves vs RCS gasket. Not much material left for gasket. Sleeves not the widest, OD 74.5mm (ID 70mm)



(There are o-rings with tight fit around sleeves pressed down before filled up with sealer.)
« Last Edit: March 16, 2025, 02:30:27 AM by PeWe »
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967