Topic: 1976 Honda cb750K

[BenelliSEI]

Looking for something else today and found THREE of the chain oiler lock tabs I needed a week ago! I need to spend a few hours and do an inventory, and stop buying stuff I already have!

[willbird]

Where do you buy a tea caddy?

I did a quick search at Maomart and they have smaller ones, but not ones made for 1/4 ounce of tea like these guys are rocking LOL.

[Stev-o]

Where do you buy a tea caddy?

My wife uses them for tea, I will steal one from the silverware drawer! Or go to Amazon...

https://www.amazon.com/dp/B0BYSDYPNZ/ref=twister_B0BYSC4NNZ?_encoding=UTF8&th=1

[BenelliSEI]

I had a nice, new set of rubber intake manifolds on the bike. Yesterday I measured the “carb gap” between them and the air box connectors. Mmm, not enough space. Turns out they are for 1969-71. Ordered a K2/K6 set from vintagecb750.com. Not cheap, but came next day and look well made and pliable. Test fit is next.

[HondaMan]

I had a nice, new set of rubber intake manifolds on the bike. Yesterday I measured the “carb gap” between them and the air box connectors. Mmm, not enough space. Turns out they are for 1969-71. Ordered a K2/K6 set from vintagecb750.com. Not cheap, but came next day and look well made and pliable. Test fit is next.

I'd be interested in your assessment of those new boots. The ones from EMGO were junk, lasting about 2 years and self-destructing, usually cracking right at the clamps. This indicates insufficient fiber in the rubber compound itself, which is an expensive component. The EMGO versions used simple hydrocarbons and some silicone: this gave them a surface sheen, but inadequate temperature tolerance. They got hard from engine heat in a very short time, then shrank, which caused the cracking. Modern ones made with silicone elastomers could work, but they will be much softer overall (squishier) and will require a judicious screwdriver to prevent the clamps from cutting into them when new.

[BenelliSEI]

I had a nice, new set of rubber intake manifolds on the bike. Yesterday I measured the “carb gap” between them and the air box connectors. Mmm, not enough space. Turns out they are for 1969-71. Ordered a K2/K6 set from vintagecb750.com. Not cheap, but came next day and look well made and pliable. Test fit is next.

I'd be interested in your assessment of those new boots. The ones from EMGO were junk, lasting about 2 years and self-destructing, usually cracking right at the clamps. This indicates insufficient fiber in the rubber compound itself, which is an expensive component. The EMGO versions used simple hydrocarbons and some silicone: this gave them a surface sheen, but inadequate temperature tolerance. They got hard from engine heat in a very short time, then shrank, which caused the cracking. Modern ones made with silicone elastomers could work, but they will be much softer overall (squishier) and will require a judicious screwdriver to prevent the clamps from cutting into them when new.

I’ve not tried these before. No numbers, no stamping, no ID of any kind. Just the label on the box. Installing the clamps usually gives an indication. Will report.

[Galactica]

I got carb holders and boots from Vintage.  They seem fine.  Time will tell.  I got several sets over the years for my Kawasakis from Vintage’s sister store, Parts N More.  Put tons of kms on this with no problems.

[BenelliSEI]

Popped the intake manifold rubber on today and they fit really well. Lined up nicely and the carb gap measure up OK too.

[BenelliSEI]

Finished up another carb this aft.

[BenelliSEI]

-12C degrees this am, so not in a rush. These were decent to start with (thank you WideAWAKE), now really good. I’m out of those impossibly small split pins for the choke linkage rods. Need to pick up a package, next week. I need to remember to install them all BEFORE screwing down to the rack plate. So much easier.

[gearsoup]

Since the conversation has turned to carb boots; I just bought a set of OEM boots for my '76. They're still in the package, but I was a bit surprised at how stiff they are. Are they supposed to be rather squishy, or are they only supposed to yield a bit to moderate hand/finger pressure?

I've not yet taken the carbs off my bike, so these were bought under a "just in case" thought.

[BenelliSEI]

Since the conversation has turned to carb boots; I just bought a set of OEM boots for my '76. They're still in the package, but I was a bit surprised at how stiff they are. Are they supposed to be rather squishy, or are they only supposed to yield a bit to moderate hand/finger pressure?

I've not yet taken the carbs off my bike, so these were bought under a "just in case" thought.

“Yield a bit” is a good description. Sound fine. OEM from Honda? Good choice.

[gearsoup]

OEM from an eBay seller: https://www.ebay.com/itm/225990212404

[grcamna2]

OEM from an eBay seller: https://www.ebay.com/itm/225990212404

Well known quality seller with a great deal 

[BenelliSEI]

OEM from an eBay seller: https://www.ebay.com/itm/225990212404

Well known quality seller with a great deal 

+1 to that.

[BenelliSEI]

#2 carb done this am and then Gary showed up and ended up working on his TransAlp. His oil leak (very minor) is definitely coming from the rocker cover on the rear cylinder. Trying to decide if it can come off with the engine in the frame! Might be easier to ignore…..

[lash]

Tell him to carry a paper towel in his pocket. What oil?! 🥸

[BenelliSEI]

Tell him to carry a paper towel in his pocket. What oil?! 🥸

Agreed, but he’s looking for stuff to do. I suggested he change the change sprockets and chain on the Varadero, but he went home instead!

[HondaMan]

Since the conversation has turned to carb boots; I just bought a set of OEM boots for my '76. They're still in the package, but I was a bit surprised at how stiff they are. Are they supposed to be rather squishy, or are they only supposed to yield a bit to moderate hand/finger pressure?

I've not yet taken the carbs off my bike, so these were bought under a "just in case" thought.

The real Honda OEM boots are hard. This makes them hard to install-remove, too! I use silicone grease on them and the engine's spigots, and sometimes have still had to employ a strap wrench to get them on.

[BenelliSEI]

Spent a bit more time on the carbs today. I think I take too long on them, but I find if I get them just right my project bikes run great right from the start. We’ll see.

[BenelliSEI]

Finished up the last carb today. It had the weirdest black, crusty staining in the bowl. Would not come away, so “borrowed” one from another set. Had to run some errands in town and stopped at 3-4 shops before I found a pack of cotter pins small enough to pass through the operating levers for the choke mechanism! They really are tiny.

CCS Industrial Fasteners, Peterborough, Ontario. The counter guys searched for quite a while and finally found a bag of them. They were so dusty they gave them to me. Great service!

Setting float heights and bench sync next time, and getting close to firing it up. Need to dig through my tub of manifold clamps and find a nice set.

[denward17]

Good progress John.

You probably don't have riding weather for a few more weeks?

[BenelliSEI]

Good progress John.

You probably don't have riding weather for a few more weeks?

Dennis….. not in any rush. Winter came back here with a vengeance today. Might be a few months yet!

[BenelliSEI]

Winter is back and the shop was +60F today. Started off by polishing a few of the original manifold clamps. Mindless work, that changes little, but really makes the finished product look right. Also replaced the dead oil pressure sending unit with another one I had in a bin. Easier to do this before the carbs go back on. It sends a ground and lights up the oil light. Hopefully it will go off too!

[BenelliSEI]

Set the float heights and added in a fresh set of bowl gaskets. Cleaned out my small ultrasonic tank and was astounded at the amount of fine silt in the bottom. These carbs were pretty good looking to start with (I almost left them alone). I did them one at a time, rotating them regularly in the tank, for about 40 minutes each. Had the heat around 30C. They are spotless.