Author Topic: K6 single carb, SOHC  (Read 14941 times)

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Offline AstroWing

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Re: K6 single carb, SOHC
« Reply #25 on: December 28, 2012, 05:07:28 AM »
brandEN - I just read the history of your build. I'm very impressed. I wasn't on any forums during my Nelsonore build, I think I may have saved myself a lot of headaches. You and I went down many of the same paths, broken head studs, tank sealing, my self inflicted thread damage was the retainer threads for the front wheel bearings (later I learned to drill the factory prick punch locks) I am running Dyna ignition and read that yours gave you some problems, maybe you can help me avoid the same issue. I, like you was lucky enough to also find a '75f rear wheel. I wish I had known that there was drill templates for brake rotors. (I took a disc off one of my other bikes and transferred the holes)  I did not like the look of the '75 brake caliper on top, so I made a simple bracket and mounted an EBay rear brake / master cylinder, I am very happy with the result. I really enjoy building custom bikes. I try to simplify and lighten everything while not spending too much money.
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Offline AstroWing

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Re: K6 single carb, SOHC
« Reply #26 on: December 28, 2012, 08:48:42 AM »
Found a solution today to a small problem that has been bugging me for awhile. When I moved the foot pegs back, I didn't have a proper length bolt for the lower-rear motor mount. I went to Lowe's got a length of 1/2" all thread. Cut it to 12 1/2" bought two stainless acorn nuts. Now I'm happy.
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Offline AstroWing

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Re: K6 single carb, SOHC
« Reply #27 on: December 28, 2012, 08:51:02 AM »
Another small issue done. My shift linkage and other items are off at the chrome shop.

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Offline Stev-o

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Re: K6 single carb, SOHC
« Reply #28 on: December 28, 2012, 05:07:36 PM »
Sounds like you have a connection at the chrome shop?  Why wouldnt you use stainlees clamps for the carb kits?
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline AstroWing

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Re: K6 single carb, SOHC
« Reply #29 on: December 28, 2012, 08:02:59 PM »
Hello, yes the chrome shop is a few miles from me. They are close, do nice work, call me by name and are alway very nice. Expensive but nice.

I had stainless clamps on there but I didn't like the way they looked. Almost gave up, then the other day I was digging thru an old tool supply store looking for something else and I found a box of clamps that fit and looked good. They are zinc plated but so old they had lost any shine they might have had. 10 clamps for $1.00 and $??? each for plating.
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Offline AstroWing

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Re: K6 single carb, SOHC
« Reply #30 on: February 12, 2013, 05:33:49 PM »
Sorry, I have been busy for more than a month. I'm still busy, but got a few minutes so I'll send a few pictures.  Here is my manifold.
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Offline AstroWing

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Re: K6 single carb, SOHC
« Reply #31 on: February 12, 2013, 05:35:35 PM »
Another manifold picture.
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Offline AstroWing

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Re: K6 single carb, SOHC
« Reply #32 on: February 12, 2013, 06:01:04 PM »
Some say that a single carb with unequal length intake runners will run lean on the outside cylinders.
Think about it this way.
Fuel/air is pulled into the cylinder as the piston moves down with the intake valve open. The carb sets the mixture as the air passes over the jets pulling fuel. Each piston pulls about the same amount of air/fuel thru the carb. Why would the outside cylinders run lean?
People think the carb pushes fuel/air into the engine when it actually only responds to the vacuum created by the piston.
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Offline dusterdude

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Re: K6 single carb, SOHC
« Reply #33 on: February 12, 2013, 07:00:09 PM »
If this thing works,i want one
mark
1972 k1 750
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1998 cbr600 f3

Offline Greggo

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Re: K6 single carb, SOHC
« Reply #34 on: February 12, 2013, 07:59:06 PM »

Offline Retro Rocket

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Re: K6 single carb, SOHC
« Reply #35 on: February 12, 2013, 08:34:08 PM »
Some say that a single carb with unequal length intake runners will run lean on the outside cylinders.
Think about it this way.
Fuel/air is pulled into the cylinder as the piston moves down with the intake valve open. The carb sets the mixture as the air passes over the jets pulling fuel. Each piston pulls about the same amount of air/fuel thru the carb. Why would the outside cylinders run lean?
People think the carb pushes fuel/air into the engine when it actually only responds to the vacuum created by the piston.

It would run lean because of what trueblue said, fuel sheeting as the fuel goes round the corners of the outer cylinder manifold, plus it would take more vacuum to draw the fuel through the longer runners at the same velocity sa the shorter runners,  actually, i think it was POSA that did a single carb manifold for the 750 in the 1970's {Terry has one}, it had the same problems mentioned....
I don't think anyone here thinks a carb "pushes" fuel into the port. Fuel sheeting is also a common problem on polished intake ports, that is why you should NEVER polish intake ports.... Port them out by all means but never polish....  I like the look of this bike and think it will be even better with sensible rubber... ;D
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Offline racinchase

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Re: K6 single carb, SOHC
« Reply #36 on: February 13, 2013, 06:45:26 AM »
Very Cool.
“The right bike, the right day, the right road, I just pretty much feel at one with the universe. When I feel like I don’t fit anywhere or I’m lonely or I’m all screwed up in the head, I get on my bike and go for a ride and it’s like all of the sudden, I’m fixed.” – Indian Larry

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Offline Vinhead1957

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Re: K6 single carb, SOHC
« Reply #37 on: February 13, 2013, 09:32:10 AM »
Very nice work! The clamps give it an extra bling!   

Offline greenjeans

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Re: K6 single carb, SOHC
« Reply #38 on: February 13, 2013, 10:33:53 AM »
Great build.   Very unique - getting harder to creat an interesting cafe/non-stock restomod or whatever you call them these days.

Great color choices.   I just love the overall look.   Well done.
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Offline AstroWing

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Re: K6 single carb, SOHC
« Reply #39 on: February 13, 2013, 09:32:00 PM »
Here is a newer picture
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Offline 754

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Re: K6 single carb, SOHC
« Reply #40 on: February 13, 2013, 09:40:29 PM »
  I love the paint..I want to do that to my 750 tracker, and call it…......
.................... HELLsinore......
Maker of the WELDLESS 750 Frame Kit
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My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline AstroWing

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Re: K6 single carb, SOHC
« Reply #41 on: February 13, 2013, 09:55:08 PM »
I really enjoy riding this bike. I did not enjoy it much when it had the 4 stock carbs.

This is a Mikuni round slide. I had to stiffen up the throttle spring because it would not always return to idle. The stiffer throttle spring requires a little more effort than I prefer. Does anyone think a flat slide Mikuni would work better with a stock spring?
I read somewhere that some Norton guys have the same problem when they use this carb. I believe there is so much vacuum being pulled by my 836 bore that the round slide needs the extra spring to squeeze the rush of air or maybe the slide is pulled so hard against the engine side of the carb that it binds, not sure which but the stiffer spring fixed it... I am building a Gold Wing, cafe now and I may test my flat slide idea on it. You guessed it, my Gold Wing won't have 4 carbs when I'm done.
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Offline AstroWing

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Re: K6 single carb, SOHC
« Reply #42 on: February 13, 2013, 10:09:14 PM »
HELLsinore. I like that!

Took me awhile to match the Elsinore paint codes. If anyone needs them, let me know.

Besides the GoldWing project, I'm also building a '73 Harley Z90. (I take in stray bikes, like the crazy cat lady takes in stray cats)
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Offline ekpent

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Re: K6 single carb, SOHC
« Reply #43 on: February 15, 2013, 06:35:14 AM »
Where did you hide the oil tank ? Looks like maybe a section of the fuel tank.

Offline Vinhead1957

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Re: K6 single carb, SOHC
« Reply #44 on: February 15, 2013, 09:37:57 AM »
I think it is time for you to patent and sell that idea.   

Offline AstroWing

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Re: K6 single carb, SOHC
« Reply #45 on: February 15, 2013, 04:06:23 PM »
Where did you hide the oil tank ? Looks like maybe a section of the fuel tank.

The oil tank is under the gas tank. Left enough clearance around it to keep from heating up the gas too much. Used a big 70's Kawasaki triple, H1 tank, still holds about 3 gallons.
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Offline Stev-o

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Re: K6 single carb, SOHC
« Reply #46 on: February 15, 2013, 05:43:45 PM »
Very clever. Although personally, I wouldn't have cut an H1 tank (because I want an H1)
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline AstroWing

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Re: K6 single carb, SOHC
« Reply #47 on: February 16, 2013, 04:40:38 AM »
I think it is time for you to patent and sell that idea.

Thanks, I am so busy with my "day job" building bikes is my way of putting it all behind me when I can. I think my manifold and a few other parts will help others to enjoy their SHOC's more. My college student son volunteered to manage the manufacturing and sales of these parts. (He is taking business classes) I will make sure he charges a fair price.  Should be fun.

Gary
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Offline AstroWing

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Re: K6 single carb, SOHC
« Reply #48 on: February 16, 2013, 04:47:19 AM »
Very clever. Although personally, I wouldn't have cut an H1 tank (because I want an H1)

Thanks, I also welded a Honda Elsinore gas cap on the H1 tank. The donor Elsinore tank was really in rough shape, as was the H1 tank. It took me several days of building up my courage before I could start cutting on those classic tanks.
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Offline Bill/BentON Racing

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Re: K6 single carb, SOHC
« Reply #49 on: February 17, 2013, 07:40:02 AM »
Nice work,nice bike.Loved the Elsinore paint.Do you know the story behind the green color? Sold my original 74 CR125 last year,still had the info stickers on tank and the rear fender!,Got $2500.00 from a buddy.Remember in 74 getting my first one in Fayetteville,N.C. was $851.00 out the door! ;D Fond memories,came off a TM125 Suzuki,that Honda off the truck could win!! ;) Bill 250 was sweet,125 even better!! 8)
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