Author Topic: my "crashed doing 80 and somehow lived" k4 750 rebuild  (Read 8382 times)

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Offline SOHC4 Cafe Racer Fan

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Re: my "crashed doing 80 and somehow lived" k4 750 rebuild
« Reply #50 on: October 31, 2016, 11:11:05 AM »
Looks good with the stock seat.  Are you still going to fit on the aftermarket brat-style seat with hinges?
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Offline nobody

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Re: my "crashed doing 80 and somehow lived" k4 750 rebuild
« Reply #51 on: October 31, 2016, 12:36:22 PM »
I don't know, I might just get a redone stock seat. I like the way it looks too. That's still another $200 away though, with a bunch of other parts higher on the "to buy" list, so who knows.
74 cb750k

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Offline nobody

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Re: my "crashed doing 80 and somehow lived" k4 750 rebuild
« Reply #52 on: November 14, 2016, 12:00:07 PM »
Got a new (used) clutch cable hooked up last week only to notice now my tach was dancing like some wacky inflatable arm flailing tube man.

So I switched out my nonfunctional, undamaged tachometer...


...with the functional but damaged one from when I crashed


A bandage to make it aaaaaaaall better
74 cb750k

If life hands you lemons, make lemonade. If life hands you tomatoes, make tomato soup. If life hands you a box of hand grenades... well, now... THAT'S a message!!

Offline nobody

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Re: my "crashed doing 80 and somehow lived" k4 750 rebuild
« Reply #53 on: November 14, 2016, 12:17:02 PM »
With the bike all functional again I decided to do a shake down mountain run since this Colorado winter is waiting to settle in. Rode a total of 90 miles on pass roads, Lookout Mountain to Red Rocks and then back to Lookout Mountain. Ran the bike through all of it's paces, even ran up to 105 once. With these Hagon shocks it hugs the ground real well, though I think I need to adjust them a little softer. The steering damper definitely provides rigidity to the steering feel, well worth adding on in my mind. The Cycle X exhaust breathes a little better, much much louder, and the air box drilling seems to have really improved throttle response, no lag whatsoever when I twist WOT, kinda touchy actually.

All these months of frustration and waiting were validated, well worth it.

74 cb750k

If life hands you lemons, make lemonade. If life hands you tomatoes, make tomato soup. If life hands you a box of hand grenades... well, now... THAT'S a message!!

Online Stev-o

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Re: my "crashed doing 80 and somehow lived" k4 750 rebuild
« Reply #54 on: November 14, 2016, 08:58:48 PM »
Doesn't the bad tach have a good chrome backing cover?
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Offline nobody

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Re: my "crashed doing 80 and somehow lived" k4 750 rebuild
« Reply #55 on: November 15, 2016, 08:04:19 AM »
Yeah, the shell of the bad tach is all good. I'll probably be buying some clamp rings from Joker Machine this winter and swapping the guts.



I guess the build is never done, now that I have it back together I have a mental list of about another thousand dollars worth of parts I want to buy...
I need to get rich somehow, and soon!
« Last Edit: November 15, 2016, 08:06:03 AM by matthew gabrielse »
74 cb750k

If life hands you lemons, make lemonade. If life hands you tomatoes, make tomato soup. If life hands you a box of hand grenades... well, now... THAT'S a message!!

Offline nobody

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Re: my "crashed doing 80 and somehow lived" k4 750 rebuild
« Reply #56 on: August 17, 2017, 12:49:52 PM »
So I'm still not rich, and this bike has barely moved in the last 9 months. Started popping main fuses after two or three more rides... le sigh.

So now I've gone and switched the coils, wires, plugs as well as a full harness from www.vintagecb750.com , fits perfect but I must've done something wrong. I get tail/brake lights, gauges, cluster while on the park circuit, but when I switch it to ignition everything but the tail lights drops off... yaaaaaaaay

74 cb750k

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Offline calj737

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Re: my "crashed doing 80 and somehow lived" k4 750 rebuild
« Reply #57 on: August 17, 2017, 01:07:24 PM »
There's a known issue with needing to add jumper in the headlight bucket for that. I don't have a link to that modification, but I would expect it's the cause of your issue.
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Offline nobody

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Re: my "crashed doing 80 and somehow lived" k4 750 rebuild
« Reply #58 on: August 18, 2017, 06:55:35 PM »
So I found this thread from Hondaman talking about a jumper. Mark also mentions the 5 and 7 fuses need to be switched along with this jumper piece, did that too.

http://forums.sohc4.net/index.php?topic=110284.0

Here is said jumper



And installed



After all this I do now get lights at tail AND brake, cluster, and gauge on the ignition circuit. For whatever reason I don't have headlight at all when I plug that in...

Im nervous about trying to start the motor until I'm all correct.

Any thoughts?
74 cb750k

If life hands you lemons, make lemonade. If life hands you tomatoes, make tomato soup. If life hands you a box of hand grenades... well, now... THAT'S a message!!

Offline nobody

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Re: my "crashed doing 80 and somehow lived" k4 750 rebuild
« Reply #59 on: August 18, 2017, 06:57:25 PM »
If you're wondering about all those capped wires those are all the blinkers, not running blinkers.
74 cb750k

If life hands you lemons, make lemonade. If life hands you tomatoes, make tomato soup. If life hands you a box of hand grenades... well, now... THAT'S a message!!

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Re: my "crashed doing 80 and somehow lived" k4 750 rebuild
« Reply #60 on: August 18, 2017, 10:02:11 PM »
I guess the late k models need another jumper going from the harnesses brown red to the brown white.



I now have all my lights, headlight too.

The horn is being all intermittent now though, works one second and not the next.

Also, my left coil is warm after the key has been on...

Wiring... Yaaaaaay
« Last Edit: August 18, 2017, 10:04:54 PM by matthew gabrielse »
74 cb750k

If life hands you lemons, make lemonade. If life hands you tomatoes, make tomato soup. If life hands you a box of hand grenades... well, now... THAT'S a message!!

Offline RAFster122s

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Re: my "crashed doing 80 and somehow lived" k4 750 rebuild
« Reply #61 on: August 18, 2017, 10:34:54 PM »
Left coil 1&4 is energized by the position of the points... that would be my guess.  Some coils will burn up their windings if left powered for a long time and not running.
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