What did you do to your cb750 today???

Carbs are coming on, the last one is in the u/s cleaner now, float valves all clear, main jets clear, slow jets proving a bit stubborn so may need a new set of them but so far no cost other than my time and the electric for the cleaner!

Loki
Good work what else can be said šŸ‘
 
Upgraded my starter clutch with the R6 gear a while back. Started better and ran great, and then I noticed one of the bearings had fallen out on my work bench. So I popped off the side cover and messed with the gear and bearing and now it sounds like a power drill and doesn't seem to be turning the engine and may be slipping. Everything else looked good, not missing teeth, so I'm going to assume its the gear rotor issue. Decided to order another gear, and I'll get back at it later this week.
 
Start clutch bearing fixed, now cranks and runs. Got a minor soft popping in the right side exhaust that I need to investigate. Going to drain the tank and put fresh gas in and see if that sorts it. The R6 gear upgrade on the starter definitely makes it sound like an adult motorcycle now when I hit the starter.
 
After finally getting my engine back together and in to the frame have started to sort out the wiring harness, routing it around the frame ready to connect up the various components in readiness for the first turn over to get the oil circulating ready for the first start.

Loki
 
well i don't know how this happened but i put diesel in the carbs for winter to stop this new ethanol crap gumming up the jets , before this experiment i always just drained the carbs until the warmer weather arrived. when i came to start her after draining the carbs and running petrol through them she fired up within 5 seconds on all 4 . before this every year i tried to start her she would struggle and fire on 2 then 3 and eventually 4 after nearly burning out the starter and flattening the battery. 😊
 
80 CB750K. Drained tank and bowls, refill with fresh non ethanol. warmed up and found #1 running cold. I confirmed spark with inline tester. I assume my next step s a compression test. Will read plugs. Any thoughts?
 
Sorry, a little background, bike is new to me was ridden 15 miles to my house. Poor idle was improved with fresh full tank.
 
Replying to my own thread, Idle has continued to improve. Compression, cool motor, dry Throttle wide open, Pretty consistent at 125 -130 psi. At first exhaust bend I used an infrared thermometer and Found #1 temp appx. 130f while 2&3 are 180f (ish), and #4 at 210f plus. Please s'plain it to me? Hot =Lean? Is it the proper moment to ask about "syncing"? If so , couldja point me to a sticky about carb sync that can be understood? Hint; the Doctor said that I only have two brain cells, and that one was chasing the other with a hatchet. Please and thank you.
 
Say Hello to my Little Friend.:umm: Sorry I thought I had Started a thread. I hope no one toes were stepped on.
 

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I bought a second bike (82 750c). Basically a donor bike . Found it on Craigslist (150.00) and the seller delivered it for free! The good =
4 into 4 exhaust seems in good condition. My
First bike left side has a leak.
Tank is decent
Front and rear fenders better condition than my 1st bike .
Seat in real good shape. The bad no carbs or air box. No idea about motor.
No side covers. I will pull parts I need and put it on Craigslist for free and maybe help someone else who could use it
 

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Stripped, de-rusted and re-painted my K6's clocks, their mounting bracket, warning lights holder and headlamp bowl, with rattle cans, including 2K clear. All came out well, except the headlamp bowl. Just not able to paint one half without causing overspray orange peel on the other half. Have given up. Hopefully enough coats on there to let it harden, then flatten it down and polish it up.

I have some original, past their best, minor screws, nuts and bolts to swap out, but the rolling restoration is pretty much complete. A fair amount's been done: New (a better used) head and valve cover, new valve stem seals, a re-hone (Subbed out to a trusted local engineer), new piston rings and 2 second hand carbs were required to get it running (without leaking or using oil). Frame and most brackets were blasted and powder-coated, while the engine was out. Replaced the rear hub, as the drum had corroded and delaminated. New front calliper and hoses. Chain and sprockets. One new coil. A rusty seat pan and a hungry mouse/mice led to a replacement seat (I've mouse-proofed the replacement). Plus usual service items, incl. Steering bearings, brake pads/shoes, tyres, drivechain and both sprockets, some cables (both throttle, clutch and tacho drive), switches, 1 bulb, a battery etc. Plus stuff I've forgotten, probably because I've hidden the receipts from my wife.

Thoroughly enjoyable process over 2 years. I'm determined it will be a rider. The bike was never off the road for more than 7 weeks. I've clocked up 4,000 miles so far and it seems to like regular (spirited) use.

I was lucky: gearbox and bottom end were fine, so no need to split the cases at this time. 4 decent exhausts. The tank (Antares Red) is unblemished, without rust and, apart from a 2" split on the left side-cover, they're presentable too. After minor teething issues, the bike now runs great and looks spot on. Not concours of course, but it now stands up to a close looking at.

I've learnt a heck of a lot about how the bike was put together (rather well) by Honda. I'm looking forward to learning more, but hopefully not for a while!

Many questions I had, had been asked before on here, or elsewhere on the Internet. Great resource for learning about these machines. Thanks to all who contribute. šŸ‘

Best, Martin
 
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Pics before latest work. šŸ‘

Which reminded me of the replaced fork seals, gaiters and new Hagon shocks. Receipt for the latter is now well underground in landfill. :)
 

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Completed my new exhaust, well almost just a bit of polishing to complete and a bracket to make up to support the tailpipe.
 

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Those are very nice looking bikes.
I have two barn finds I am working on.
They may look familiar lol
82 maxim650 is my daily driver. It sat for 14 years and 80 750c sat for 18 years.
Ride safe
 

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Those are very nice looking bikes.
I have two barn finds I am working on.
They may look familiar lol
82 maxim650 is my daily driver. It sat for 14 years and 80 750c sat for 18 years.
Ride safe
Great looking bikes. Mine is an 81 XJ650. Great bike to ride and super easy to work on. I just need to change the seat. Puts me to far up on the tank, and less comfortable to ride.
 

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Great looking bikes. Mine is an 81 XJ650. Great bike to ride and super easy to work on. I just need to change the seat. Puts me to far up on the tank, and less comfortable to ride.
Looks great unfortunately the chowder head who owned my bike neglected it and the oxidation is profound.
I drive it as much as possible and it is fun to ride.
So I am juggling both bikes at one time lol.
 
I washed my new (to me) 2000 750 Nighthawk, and ordered parts. The turn signals had been replaced with miniature LED units that flash too fast, so I ordered a set of original looking ones on Amazon. I also ordered a used clutch cover with dipstick form e-bay, as I am not sure that the dipstick that is on the bike is the correct one. It is binding so badly that I needed to use pliers to remove it. The threads look good on the cap and in the clutch cover but it binds all the way in and all the way out. Those dipsticks are no longer available apparently.
 
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