Topic: CB750 K0-1, the motorcycle that ate my brain gets pipes stretched!

[Don R]

  I got the head on and torqued, the outer 10mm bolt holes are so tight I can't even tighten them with my sanded down 10mm deep. I'll do my best with a big JIS screwdriver. I polished all of the dowels with a wire wheel, torqued and retorqued the head this am. rocker stands going on.
  The tachometer drive is missing. hmmmm. It looks to have been soda blasted so I must have removed it.
 Update, top end on, ready to set the valves. Still need to find the tach drive and round up 8 adjuster covers. I had to rob the cam bolts out of my diecast engine parts. I want this engine in and assembled this weekend.

[Don R]

 Victory! I made it out there this afternoon and got the engine mounted into the frame. I got a pic of the hoist and strap that I use to hang the engine. Once it's sitting there, I move the strap in between the frame tubes to swing it in further and use a couple phillips screwdrivers to line up the frame mounts.

[MauiK3]

Good progress!!

[Don R]

 Thanks! I've been stuck on the engine what seems like forever, it was one challenge after another. Thank goodness for parts engines and bikes.
 I made good progress on my old car too.

[BenelliSEI]

Good day!

[Don R]

  The motorcycle that ate my brain thought I should try the weber carbs in this big empty space. They fill it up and more.
  I did get out parts to assemble a set of 4 cable carbs. 

[MauiK3]

Do the Weber carbs make it run better?

[Don R]

Do the Weber carbs make it run better?

 Not on this bike, it was an opportunity to check the physical fitment, but I hear good things about them on 836 and bigger engines. For me, it's more about the cool factor. I've lucked into two sets of Mikuni 29 smoothbore carbs that work pretty well so these Weber carbs have been sitting ignored on the shelf of performance parts.

[Stev-o]

Do the Weber carbs make it run better?

 I've lucked into two sets of Mikuni 29 smoothbore carbs...

Hey Don...plz let me know if you ever want to sell a set, I would like to put them on my Z1. Thx

[Don R]

 The 29's off of my GS1100 had reducer rubbers to make them fit the Suzuki but they have the 1.5 slides which are suited to Honda/Kawasaki engines. I'll keep you in mind when these projects get sorted out.

 The M/C that ate my brain is getting a starter, cover, cam chain adjusted, oil press wiring, kick starter, front sprocket, for some reason my chains are too short. I didn't count links but will when I go back out. 

[Don R]

 I ordered a made in Vietnam K0 seat. The Yen is doing too well against the Dollar and the prices were a little much for my tastes. I still want a Yamiya seat for my other bike but not today. My gold bike has a DSS seat, it looks great but sits really firm.
 We will see if it catches a tariff when it lands here. I know "no politics" but this business has already affected my car project, it made a rush on steel body assemblies. Maybe the price increases will thin out the herd.

[BenelliSEI]

I had a DSS seat on my K4. It looked really good but it was as hard as a ROCK! Everybody that rode it complained about it.

[Don R]

 Agreed on the DSS seat. I got a complete set of 4 cable carbs but still need a lock nut for the adjuster on the second set, it looks like a valve stem nut in thread diameter, but the thread is even finer. There are a couple on ebay but I gust spent a grand on car stuff. I'm also short a butterfly clip again, I think when the dust settles, I'll buy a $54 4 carb kit just to get the gaskets and clips, toss the brass or make it into a small sculpture. The floats might float, who knows?
 

[MauiK3]

I have a Yamiya seat on my K3, slightly lowered, I think 20mm, which helps as I am inseam challenged. At my age, any seat gets rock hard very quickly. Otherwise it's a nice seat. Looks perfect.

[Don R]

 I took off for Sturgis on GL1000 with a bad aftermarket seat once.  It sloped towards the tank and was hard and slippery, I think it had boat vinyl on it. There isn't a lot worse than that, I was sliding forward all day and the boys were being crushed. 
 When I got to the Mt. Rushmore KOA, I borrowed a hack saw blade, peeled back the cover and carved out a wide hollow area from the foam so it supported under my legs more than under the middle and didn't slide me forward all day. Relief came late, I was still sore all weekend. I put a stock seat on it, and it was a huge improvement.

[PeWe]

My K6 seat was redone early 80's. Probably scratched in need of repair.
It was common to cut down the high and box shaped stock seats.

We had a very good car, boat, motorcycle seat (and whatever could use vinyl/ leather and foam) restore company in town back then.

It got a wave shape for the driver and passenger. More rounded and a very comfortable foam.
I could ride all day long which I did when riding to Austria.

I few years ago the bike got a NOS seat. I got pain in my left hip due to the lower distance of seat vs foot pegs with the cut down seat.
NOS seat looks better too but not as comfortable as the redone seat.

The seat will be lower when sitting on it.

[Don R]

  I spent some time on the MTAMB today, I got the K0 carbies on it and realized later that I had used the wrong set. I had intended to keep these, they have the original sticker on the right side. Oh well.
  Once I saw a bulletin that called for a notch in the triangle to let the 4 carb cables fit easier, so I made one and fed the cables through.
 Next up, I put on a black later model air box, the bike will need paint, so I'll sell it with the black airbox and include a new repro K0 box for when it gets painted.

 The Vintage CB750 K0 carb rubbers fit well, I was surprised how much smaller the engine side is, compared to the carb side. It took a little lube and some tuning of the angle to get the carbs aimed right. I had genuine airbox rubbers and picked through my stash of clamps to make a nice set.

[lash]

Where would I be able to read that bulletin?

[Don R]

  http://forums.sohc4.net/index.php?topic=196161.0

 CB750 #15 3/16/70 page 3 repair procedure A note between #5 and #6 and diagram on fig. A page 8.

 I did mine wrong, don't care. This bike didn't even have a triangle when I got it.

[BenelliSEI]

Where would I be able to read that bulletin?

See photo.

[Don R]

 I mounted the repro seat, it sets a wee bit to the right in back, it is possible that the frame side hinges are bent outwards since it had an aftermarket seat before. This beast is close to being assembled without restoration. I'll need to pick a price and throw some pics on marketplace. Some bikes need new homes, I value the space more than the projects.
 The Sandcast and one owner 750 K4 might end up on the chopping block. I've decided 4 titled and plated street bikes are enough (really too much)

[Don R]

  I bought 7 K0 sized open end wrenches off of ebay to help make a set of tools for this bike. I'll have a couple each of the 19/17 mm and 14/10 extra that I'll be able to sell or trade. These only come in the K0 tool sets as far as I know. I got one 12/8 but I'll need it. I also got the big double box end wrench for my set.
 I'll post a for sale/trade ad after they get here.
 Edit; It seems I have 4 sets of K0 end wrenches and 3 sets of later Honda wrenches.

[Don R]

 Today the K0 got a headlight, wiring bundle sheath, headlight plug, sprocket cover, starter cover, sidecover primed, I'm not going to start it but will advertise it complete with a reproduction air box and a Busso exhaust.

[Don R]

 I got the left side 4-4 pipes on, it was a minor struggle since I already had the ratchet strap and line-up tools handy. Thank you to the pioneers of the brand X pipe installation. (never say the B word)

  The first thing I would do again is taper the holes in the frame bracket to help the bolt to slide through. Good golly, it took me an hour per side to get the rear peg bolts in.
 These things are definitely not as good as Yamiya but look respectable when installed.  I would still not ever spend a dime with them again.
 
  Before and after left side.

[Don R]

 I had to bend out the center stand to clear the 4-4 pipes, a little heat and it's good now. I had a bike that had everything narrowed but I don't remember it having a center stand. Either someone modified it, or a laydown did the deed. It got bolts in the oil lines and it's looking pretty complete.
 Edit: I swapped in a nice black master cyl. and bled the brake for use in rolling it off of the lift. Wire connections, fuel lines and a battery and it could start. I really want to prime the oil system enough to flush out any dirt that may have been missed. I wasn't going to make it a runner but I think it would sell better running and riding.  One thing leads to another and six other things.