Author Topic: Early Sandcast Found......  (Read 89090 times)

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Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #900 on: March 03, 2023, 07:55:26 am »
Pulled the sump off today. No debris and the oil pump pickup screen is spotless. Primary chain is nice and tight. Great!

Offline denward17

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Re: Early Sandcast Found......
« Reply #901 on: March 03, 2023, 08:43:25 am »
Pulled the sump off today. No debris and the oil pump pickup screen is spotless. Primary chain is nice and tight. Great!

That's good news!

Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #902 on: March 03, 2023, 03:24:48 pm »
Pulled the sump off today. No debris and the oil pump pickup screen is spotless. Primary chain is nice and tight. Great!

That's good news!

It is! I ran the bike before I tore it down and it was very quiet. No chain noises at all. It did have some puck leaks, so this top end work is really to get it back to clean and dry. Replacing all the shaft seals too. All the covers came off today, will get them vapour blasted and then some polishing.

Offline PeWe

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Re: Early Sandcast Found......
« Reply #903 on: March 03, 2023, 11:00:37 pm »
Are the old clutch plates worse by age, like hardening to bad gripping surface?

When oil pan is off, is the tensioner rubber wheel rubberish or has it transformed to bakelite?
If age or oil by use will do that.
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

Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #904 on: March 04, 2023, 05:58:25 am »
Are the old clutch plates worse by age, like hardening to bad gripping surface?

When oil pan is off, is the tensioner rubber wheel rubberish or has it transformed to bakelite?
If age or oil by use will do that.

Per, I have not opened the clutch up yet, and I will. Rubber tensioner looks and feels good.

Offline PeWe

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Re: Early Sandcast Found......
« Reply #905 on: March 04, 2023, 09:09:02 am »
OK, the oil and heat can be the bad for rubber then.

Maybe there are some oils that can make rubber to stay pliable longer and lube the engine with cam as needed?

And also oils that are bad for rubber tensioners.
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

Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #906 on: March 04, 2023, 09:17:04 am »
When I picked this bike up, the oil tank, sump, and even the filter housing were empty (of oil; the filter, spring and washer were still there). Someone had written “no oil”” on the handlebars, with a felt pen. Very strange.

Offline PeWe

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Re: Early Sandcast Found......
« Reply #907 on: March 04, 2023, 09:37:22 am »
Despite that no rust inside?
If no rust, good dry bike saving storage ;)
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

Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #908 on: March 04, 2023, 01:53:29 pm »
Despite that no rust inside?
If no rust, good dry bike saving storage ;)

No. Everything had a nice film of oil. #4 piston and valves were a bit “dry”. I suspect that was the cyl. with both valves open (carbs and airbox missing). All good now.

Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #909 on: March 06, 2023, 09:52:09 am »
Cleaned out the sump and screen. New gasket, buttoned up. We are off for 6 weeks on Sunday, so paint and polished side covers will happen when the weather gets a bit warmer!
« Last Edit: March 06, 2023, 09:54:24 am by BenelliSEI »

Offline Stev-o

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Re: Early Sandcast Found......
« Reply #910 on: March 06, 2023, 10:23:11 am »
We are off for 6 weeks on Sunday...

Mind if we ask where you are headed?  I just returned from a week in Aruba!
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #911 on: March 06, 2023, 01:25:26 pm »
We are off for 6 weeks on Sunday...

Mind if we ask where you are headed?  I just returned from a week in Aruba!

My wife’s Dragon Boat Team (Survivor’s Abreast, Peterborough, ON.) is headed for the International Festival in Cambridge, N.Z. I’m tagging along, so we are going to Australia for a few weeks, then New Zealand, south to north. Ending with a 5 days on the Island of Roratonga.

Offline Don R

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Re: Early Sandcast Found......
« Reply #912 on: March 06, 2023, 06:12:04 pm »
 I know the experts say all of the sandcast motors were painted but 5511 shows no evidence of ever having paint on it. It was pulled from the frame when the PO's son had the rocker cover and side covers chromed but he says he didn't remove anything else.
   I've dechromed the left side but the 9 bolt clutch cover and the valve cover are still chrome.
  The Dad was not pleased that his bike was taken apart without permission and I think that's when it went into the shed leading to the mere 7300 miles it had when I got it.
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 BenelliSEI

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Re: Early Sandcast Found......
« Reply #913 on: March 06, 2023, 06:20:07 pm »
I know the experts say all of the sandcast motors were painted but 5511 shows no evidence of ever having paint on it. It was pulled from the frame when the PO's son had the rocker cover and side covers chromed but he says he didn't remove anything else.
   I've dechromed the left side but the 9 bolt clutch cover and the valve cover are still chrome.
  The Dad was not pleased that his bike was taken apart without permission and I think that's when it went into the shed leading to the mere 7300 miles it had when I got it.

This one is definitely painted. Oil pan has no paint and the vent box cap (3 screws on top of the cam cover) is also painted the engine colour.
« Last Edit: September 04, 2023, 05:58:56 pm by BenelliSEI »

Offline zzpete

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Re: Early Sandcast Found......
« Reply #914 on: March 16, 2023, 06:53:06 pm »
Very Cool!! Subscribed!
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Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #915 on: March 17, 2023, 08:09:47 pm »
Very Cool!! Subscribed!

Thanks! Left both my torque wrenches with the local Snap On sales rep. I bought the big one (75-250 lbs/ft) to torque the flywheel centre bolt on a 1293cc Mini Cooper “S” I first raced in 1973! The small one came not long afterwards. Thought I’d have them recalibrated before the final pull for the head.
« Last Edit: April 09, 2023, 01:55:07 pm by BenelliSEI »

Offline RAFster122s

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Re: Early Sandcast Found......
« Reply #916 on: March 17, 2023, 09:08:05 pm »
John, good idea to have them recalibrated. The advantage of buying a expensive big brand tool is services like that...
Hope your wife's boat team does well and you enjoy vacationing in AU and NZ.
David- back in the desert SW!

Offline Don R

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Re: Early Sandcast Found......
« Reply #917 on: March 17, 2023, 10:31:22 pm »
 I used my inch lbs and my ft lbs torque wrenches. The inch lb wrench stopped a little sooner but that was good with me.
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 BenelliSEI

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Re: Early Sandcast Found......
« Reply #918 on: April 16, 2023, 12:17:01 am »
We’ll be back home in a week and I can’t wait to be back in the shop! The International Dragon Boat Festival was great. +3000 Women in one spot and +50 heats! Australia and New Zealand were both places I could easily move to. Welcoming and stunningly beautiful everywhere. The population of NZ is less than Toronto!

A few days in the Cook Islands and then back to Ontario. Our race season starts in a few weeks too. Turning 70 in a bit and still “living the dream”. Cheers to good health!
« Last Edit: April 16, 2023, 12:26:58 am by BenelliSEI »

Offline RAFster122s

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Re: Early Sandcast Found......
« Reply #919 on: April 16, 2023, 01:32:13 am »
Ya have to worry about hitting sheep on the country roads in NZ and the Kangaroos in AU...
Much like the deer in Ontario countryside...if they are as thick there as in Ohio and Michigan...

Enjoy your last week in southern paradise John
 Hope the wife's team had fun and did respectable in their finish.

David
David- back in the desert SW!

Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #920 on: April 26, 2023, 04:04:23 pm »
Very Cool!! Subscribed!

Thanks! Left both my torque wrenches with the local Snap On sales rep. I bought the big one (75-250 lbs/ft) to torque the flywheel centre bolt on a 1293cc Mini Cooper “S” I first raced in 1973! The small one came not long afterwards. Thought I’d have them recalibrated before the final pull for the head.

We’re back home. Picked up my torque wrenches today. The Snap On rep discovered the big one (+50 years old) was spot on and the smaller one was less then 5% high! I always wind them back to “0” and store them back in the hard case, when not in use. Seems to work.

All the engine covers that went out for VBlasting (they were rough) are ready for pick up. It will be interesting to see how they turned out. Hopefully I can get them in the next few days. First Test Day with race car is Sunday, first race weekend is in two more weeks. Fun times!


Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #921 on: April 28, 2023, 03:08:31 pm »
Picked up the engine covers today. Amazing results. They were really rough, corroded and flaky. I’ll take pictures tomorrow. I’ll have to strip down the carbs and get the bodies, float bowls, and tops done too. Really nice finish.

Offline denward17

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Re: Early Sandcast Found......
« Reply #922 on: April 28, 2023, 05:18:14 pm »
^ Good to hear, can't wait to see pictures.

Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #923 on: May 01, 2023, 10:04:19 am »
^ Good to hear, can't wait to see pictures.

Here they are. Polish or leave them alone?

Offline JamesH

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Re: Early Sandcast Found......
« Reply #924 on: May 01, 2023, 10:05:33 am »
Polish gets my vote. Would look totally wrong as-is imho.