Author Topic: Early Sandcast Found......  (Read 89246 times)

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Offline MauiK3

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Re: Early Sandcast Found......
« Reply #825 on: January 14, 2023, 01:26:32 pm »
I wonder if using glass beads on the backs of valves would be a good way to clean them.
The glass shouldn’t damage the metal but who knows.
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Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #826 on: January 14, 2023, 06:05:36 pm »
I wonder if using glass beads on the backs of valves would be a good way to clean them.
The glass shouldn’t damage the metal but who knows.

A lot of guys seem to do a lot more. I think it’s a waste of time. These valves were sitting perfectly in the head, no leaks (I had it upside down, with plugs installed. Filled the chambers with varsol and zero leaks). I just knock 99% of the crust off with the 3M pad and some varsol. I do sand off the valve faces, enough so the lapping tool will stick to them. They’ll look like this again, soon enough.

Offline Rddmm2

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Re: Early Sandcast Found......
« Reply #827 on: January 16, 2023, 10:10:29 am »
John,
Great project thread.  Wow, your bike is a unique and rare early model with very distinct and one-off characteristics, and found in beautiful Southern Ontario! What an amazing find.
I recently pulled the motor on my late model sandcast.  It was leaking oil through the fins. I decided to bring the valve and cylinder head to Gord Bush Performance in Etobicoke Ontario.  You may know him, he's a motor rebuild guy with a race history at Mosport. The cross-patch pattern was still visible and in good shape, so he cleaned them up with a light hone and I had valves done.  I'm hoping to reassemble and have it back on the road this Spring.   Its been one of the great thrills of my life having the chance to ride this thing around.             
I have a gasket kit from Yamiya, but I wonder if you have ever used a supplier in Ontario for engine reassembly bits such as piston ring kit, etc.  Cheers.

Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #828 on: January 16, 2023, 01:54:05 pm »
John,
Great project thread.  Wow, your bike is a unique and rare early model with very distinct and one-off characteristics, and found in beautiful Southern Ontario! What an amazing find.
I recently pulled the motor on my late model sandcast.  It was leaking oil through the fins. I decided to bring the valve and cylinder head to Gord Bush Performance in Etobicoke Ontario.  You may know him, he's a motor rebuild guy with a race history at Mosport. The cross-patch pattern was still visible and in good shape, so he cleaned them up with a light hone and I had valves done.  I'm hoping to reassemble and have it back on the road this Spring.   Its been one of the great thrills of my life having the chance to ride this thing around.             
I have a gasket kit from Yamiya, but I wonder if you have ever used a supplier in Ontario for engine reassembly bits such as piston ring kit, etc.  Cheers.

Gord Bush’s shop does excellent work! I usually try and buy parts from Honda first. It’s surprising how many things you can still get from them. I also order lots from vintagecb750.com, it usually arrives next day. Get your bike ready for the Ganaraska 250, we already have 5-6 that run the event every Spring. That’s me in the middle, my son is left of centre.  John D.
« Last Edit: January 16, 2023, 01:57:49 pm by BenelliSEI »

Offline Rddmm2

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Re: Early Sandcast Found......
« Reply #829 on: January 16, 2023, 07:49:05 pm »
Thanks for info. That’s a great pic.  Some inspiration for the Spring right there.
I’m using some tips shared in your project thread to help with my top end rebuild and re-assembly. The  ‘while I’m at it’ list is growing.  The vintagecb750 website of parts looks good.

Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #830 on: January 17, 2023, 11:55:53 am »
Good afternoon in the shop. Completely dismantled the original seat. Cover and foam are not worth saving, BUT managed to get it all apart without damaging chrome trim strips, or the “rivets” and crimp washers that retain them. Miraculously, not one of the tiny triangle tabs that lock down the cover broke off! My history with those is not good. The pan seems thicker than most and it’s obvious this bike was never left outside.....

Next will be sandblasting the pan and giving it a good coat of fresh paint. Suggestions on foam and cover? Off to the Yamiya website next.

Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #831 on: January 18, 2023, 10:11:35 am »
Nice solid pan!

Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #832 on: January 18, 2023, 10:17:53 am »
Only some of you will appreciate where the time goes! Today I spent more than an hour reworking the original trim strips for the seat. They were pretty crusty to start with. Shaped a wooden punch (ex clothes pin) and tapped away a few creases. Cut small strips of 3M Scotchbrite to polish out the inside track. Autosol and Chrome polish did a nice job of all the exposed portion.....

It would be easier to just order new stuff, but I am determined to reuse +95% of this machine! Very satisfying.

Crap! Yamiya is out of “red foam” kits for my seat! Anyone have one in their inventory?
« Last Edit: January 18, 2023, 11:07:08 am by BenelliSEI »

Offline Don R

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Re: Early Sandcast Found......
« Reply #833 on: January 19, 2023, 06:40:22 am »
 Get the regular seat foam and push some small strategically trimmed pieces of the old red foam through the seat pan holes.
   Not my invention, there is an underground supply of red foam stocked by sneaky K0/sandcast guys around here. Shhh, don't tell anybody, it's a secret. 
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 #834 on: January 19, 2023, 06:47:05 am »
Get the regular seat foam and push some small strategically trimmed pieces of the old red foam through the seat pan holes.
   Not my invention, there is an underground supply of red foam stocked by sneaky K0/sandcast guys around here. Shhh, don't tell anybody, it's a secret.

Don..... Considered that but the old red foam in my seat is totally shot. I tried slicing into inside pieces and it’s just as “crumbly” as the exposed stuff. Totally disintegrated, through and through.....

Offline MauiK3

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Re: Early Sandcast Found......
« Reply #835 on: January 19, 2023, 07:04:33 am »
Fantastic project
Good luck on red foam.
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Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #836 on: January 19, 2023, 07:07:59 am »
Fantastic project
Good luck on red foam.

Yamiya emailed back “they don’t know” when they’ll be back in stock. I’ll be patient. Last time I waited 3-4 weeks to the “two hole air filter hardware kit”. I’ve got lots of other stuff to do!
« Last Edit: January 19, 2023, 07:10:45 am by BenelliSEI »

Offline RAFster122s

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Re: Early Sandcast Found......
« Reply #837 on: January 19, 2023, 10:21:25 am »
You could always borrow another seat for a while waiting on the supply to catch up...
David- back in the desert SW!

Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #838 on: January 19, 2023, 12:39:58 pm »
True! I’m sure it will be available by the time I finish everything else!

Offline Don R

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Re: Early Sandcast Found......
« Reply #839 on: January 19, 2023, 03:40:26 pm »
 I've been watching for them for quite a while, I think a couple did turn up a while back, I'm not sure if they were someone's old stock or if Yamiya did get some back ordered ones shipped out.
 
  My several year old Yamiya red foam has already begun to make dust under the seat, there may be a reason they don't have any. I complained recently it's never been wet or frozen and has rarely seen any sun. I installed a plastic bag over it and under the cover so the skin so soft didn't soak in or anything.
« Last Edit: January 19, 2023, 03:52:33 pm by Don R »
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 #840 on: January 19, 2023, 05:09:14 pm »
I've been watching for them for quite a while, I think a couple did turn up a while back, I'm not sure if they were someone's old stock or if Yamiya did get some back ordered ones shipped out.
 
  My several year old Yamiya red foam has already begun to make dust under the seat, there may be a reason they don't have any. I complained recently it's never been wet or frozen and has rarely seen any sun. I installed a plastic bag over it and under the cover so the skin so soft didn't soak in or anything.

Don.... did you use Yamiya’s cover or? I’ve already used a few that were well made, in the USA, and are significantly less (the ones sold by vintagecb750.com). They have a nice quilted material under the centre portions and fit really well.
« Last Edit: January 19, 2023, 05:11:21 pm by BenelliSEI »

Offline Don R

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Re: Early Sandcast Found......
« Reply #841 on: January 19, 2023, 07:52:40 pm »
 I was able to re-use the original cover. I've also used some really good replacement covers. I may have some usable red foam. I'll see if it will slice thin and not crumble.
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 #842 on: January 20, 2023, 05:54:57 am »
I was able to re-use the original cover. I've also used some really good replacement covers. I may have some usable red foam. I'll see if it will slice thin and not crumble.

Don.... Don’t worry about it. I’ll refinish the pan and just put it to one side. I’ve got plenty of other stuff to finish yet! This morning I figured out their “replica, white foam seat” is only $100 more than the supplies I need to refurbish the original! However, I’m sticking to my plan. Reuse as much as I posssibly can.....

Offline Stev-o

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Re: Early Sandcast Found......
« Reply #843 on: January 20, 2023, 07:25:49 am »
Fantastic project
Good luck on red foam.

Yamiya emailed back “they don’t know” when they’ll be back in stock.

Hey John...are you on the Sandcast forum? If yes, maybe one of those guys has a spare they would be willing to sell?
'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 #844 on: January 20, 2023, 08:13:43 am »
Fantastic project
Good luck on red foam.

Yamiya emailed back “they don’t know” when they’ll be back in stock.

Hey John...are you on the Sandcast forum? If yes, maybe one of those guys has a spare they would be willing to sell?
Good idea. Thanks.

Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #845 on: January 25, 2023, 01:41:52 pm »
Got a call that the vapour blasting is done. Too bad we’re getting hit with our second MAJOR snowstorm of the winter! Might be a few days before I retrieve the parts.....

Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #846 on: January 27, 2023, 02:53:29 pm »
Picked up the parts that were vapour blasted today and they are spectacularly clean! On the way home, dropped into a small shop. Paul is well known for repairing 100 year old, 4 cylinder Indian engine crankcases! The one on his bench had three rods poke holes in the side. #2 took a huge chunk out, right through the sump flange. He was busy casting a new piece and jigging up the case 1/2 for welding. Amazing work!

I left him the barrel portion of S/C engine, for bent fin repairs. He seemed to think it would be relatively simple and intends to rebuild the two spots where I had to whack it with a large brass drift, to get it to “pop”..... He’s also got a honing machine, so offered to prep my bores for new rings. One stop shop. Great!

Pictures next time.
« Last Edit: January 27, 2023, 07:07:20 pm by BenelliSEI »

Offline MauiK3

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Re: Early Sandcast Found......
« Reply #847 on: January 27, 2023, 03:08:06 pm »
It’s pouring here today but all is well.
That shop sounds great.
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Offline BenelliSEI

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Re: Early Sandcast Found......
« Reply #848 on: January 27, 2023, 07:04:01 pm »
It’s pouring here today but all is well.
That shop sounds great.

Your weather goes down the Drains! Photos of head. Spotless.....

Offline RAFster122s

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Re: Early Sandcast Found......
« Reply #849 on: January 27, 2023, 11:42:04 pm »
Vapor blasting looks to be top shelf work! That fellow’s shop sounds like a place that would be fantastic to hang out and watch the fellow work if he didn’t mind your presence. The old ways and skills of a lot of old machinists and other craftsmen is fascinating to watch… sometimes you see the logic in their steps and learn new ways to approach things. Often these guys apprenticed with guys and you see generations of knowledge in action. When I was starting out in product engineering after college I got to hang out with a few machinists and a facilities maintenance guy and I enjoyed learning from the old guard. It opened my eyes to different solutions and the one machinist did maintenance and refurbishment and periodic rebuilds on some of our equipment that was probably 75 years old then, mid 80s.
Lost artisan ways…
David- back in the desert SW!