Author Topic: CB750K4 what did I get myself into?  (Read 11463 times)

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Offline HondaMan

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Re: CB750K4 what did I get myself into?
« Reply #275 on: April 22, 2024, 07:52:18 PM »
I have seen, with chains that are pre-lubed with a heavy oil/grease, the rear wheel's adjuster marks are clear forward of the front mark when installing the chain. After about 10 miles the grease oozes out of the links and the chain becomes very loose in those situations. This varies by the chain maker, as they all have their 'secret clearance' numbers they use for their chain. When assembling the post-K2 thru K5 versions of these bikes from their crates (brand new) they chains were always very taut (RK brand chains then) and we left them alone: by the 300-mile checkup they were always very loose.
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

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Offline BrockCB750

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Re: CB750K4 what did I get myself into?
« Reply #276 on: April 28, 2024, 12:09:31 PM »
After a boneheaded wiring mishap I have made some progress. Starter wired up and turns the bike over nicely!



https://hosting.photobucket.com/images/r798/WBlacklidge/VID20240428144841_2.mp4

Offline BrockCB750

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Re: CB750K4 what did I get myself into?
« Reply #277 on: April 28, 2024, 03:15:58 PM »
Everything wired up from coils to dyna ignition. Set timing. Wanted to start it up but realized I need the correct size fuel line.

Hopefully tomorrow!

Offline BrockCB750

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Re: CB750K4 what did I get myself into?
« Reply #278 on: April 29, 2024, 05:57:11 AM »
Going to wire up the oil pressure switch just so I can verify I have oil pressure. Also going to wire in the kill switch just in case.

I put oil in the oil tank and turned it over a bunch. Everything is really smooth.

Any other concerns I should have before attempting to start her up?

Thanks!

Offline BrockCB750

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Re: CB750K4 what did I get myself into?
« Reply #279 on: April 29, 2024, 04:51:20 PM »
Well first attempt to start it sputtered a little then gave up. Didn't realize I had run the battery down so far checking for oil pressure. Going to give it another shot here in 15 minutes and call it a night.

This week looks like I will be chasing down spark, fuel and air.

Offline BrockCB750

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Re: CB750K4 what did I get myself into?
« Reply #280 on: April 29, 2024, 05:00:24 PM »
Well... I don't believe it but...backed the choke off 1/4 from full and it started right up. Idled great! All four cylinders firing based on exhaust temp. I am in shock right now. That felt amazing.

Online denward17

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Re: CB750K4 what did I get myself into?
« Reply #281 on: April 29, 2024, 05:02:43 PM »
Good news Brock!

Offline BrockCB750

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« Last Edit: April 29, 2024, 05:47:21 PM by BrockCB750 »

Online denward17

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Re: CB750K4 what did I get myself into?
« Reply #283 on: April 29, 2024, 07:13:09 PM »
The instagram link worked for me, sounds great.

Offline BenelliSEI

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Re: CB750K4 what did I get myself into?
« Reply #284 on: April 30, 2024, 04:33:00 AM »
Well... I don't believe it but...backed the choke off 1/4 from full and it started right up. Idled great! All four cylinders firing based on exhaust temp. I am in shock right now. That felt amazing.


Congrats! Nothing feels more satisfying than that first start!

Offline BrockCB750

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Re: CB750K4 what did I get myself into?
« Reply #285 on: April 30, 2024, 04:52:23 PM »
Thanks!

Got some more gas and started it up again. Definitely needs some adjustment. Some common problems like idle hanging after any amount of throttle. It could be anything except the throttle linkage which snaps right back. No big deal I have literally done nothing to diagnose or resolve.

Current state is that its wired just enough to run and what is wired up isn't done well.

Trying to decide:

1) Tune it and get it running better now then wire everything up.
2) Work on wiring it up more complete, safe and asthetic. Then tackle any engine adjustments while I have the ability to also ride it.

I am leaning towards #2 because while I can tune and get it running better at idle and with some throttle I absolutely can't ride it under load and get a feel for it. Also, the janky wiring makes me nervous. Finally, the goal was to see that it can run and nothing major was wrong. That seems to be the case.