Saving a 1980 750 twin.

Scirocco
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Re: Saving a 1980 750 twin.

29 Jul 2019 13:01 - 29 Jul 2019 13:02

I would put an oil cooler on the "To-Do-List" first. Bronze bushing the connecting rod for the wrist pin is a must have mod for tuned engines.
High Performance engines had and extra oil line (Jet) that spayed oil to the bottom of the piston and wrist pin for cooling and lubrication.

My 1975 Z 1 B 900 Project

www.kzrider.com/forum/11-projects/605133...ears-deep-sleep-mode

Last edit: 29 Jul 2019 13:02 by Scirocco.

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DoctoRot
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Re: Saving a 1980 750 twin.

29 Jul 2019 13:34

#808366

Hmmm, I wonder if it would be possible to make that happen

'78 1000 Long Term Project
'80 750G
750 Twin Big Bore Track Bike

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SWest
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Re: Saving a 1980 750 twin.

29 Jul 2019 14:12 - 30 Jul 2019 09:22

#808368

This is for the cam chain in my daughter's car. It sprays in two directions.
Steve

Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229

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Last edit: 30 Jul 2019 09:22 by SWest. Reason: sp

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bluej58
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Re: Saving a 1980 750 twin.

29 Jul 2019 16:47

#808378

Heavier cross hatching ?

78 KZ1000 A2A

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DoctoRot
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Re: Saving a 1980 750 twin.

30 Jul 2019 09:41 - 30 Jul 2019 16:11

#808429

Some people smarter than I are thinking there may have been detonation. I found a video of the sound it was making. Thoughts? it was only coming from the right side and from the valve cover.

'78 1000 Long Term Project
'80 750G
750 Twin Big Bore Track Bike

Last edit: 30 Jul 2019 16:11 by DoctoRot.

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bluej58
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Re: Saving a 1980 750 twin.

30 Jul 2019 14:19 - 30 Jul 2019 14:20

#808438

.

78 KZ1000 A2A

Last edit: 30 Jul 2019 14:20 by bluej58.

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DoctoRot
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Re: Saving a 1980 750 twin.

16 Nov 2019 23:44 - 16 Nov 2019 23:49

#814079

getting a move on this. I decided to bite the bullet and get some custom JE pistons in 86mm bore. this will put the bike at 906cc. If you would like to get in on a limited run of pistons and sleeves let me know soon as I will be pulling the trigger on this in the near future.

Attachment IMG_0820.JPG not found

'78 1000 Long Term Project
'80 750G
750 Twin Big Bore Track Bike

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Last edit: 16 Nov 2019 23:49 by DoctoRot.

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DoctoRot
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Re: Saving a 1980 750 twin.

21 Feb 2020 22:51

#819671

Think I found the source of the noise... unfortunately this went south so fast it damaged the crank as well

'78 1000 Long Term Project
'80 750G
750 Twin Big Bore Track Bike

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Nebr_Rex
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Re: Saving a 1980 750 twin.

22 Feb 2020 04:10

#819678

Go back to the post you made on Nov. 11 2018. Looks like the crank had issues from the start.

.

2002 ZRX1200R
81 GPz1100
79 KZ1000st daily ride
79 KZ1000mk2 prodject
78 KZ650sr
78 KZ650b
81 KZ750e
80 KZ750ltd
77 KZ400/440 cafe project
76 KZ400/440 Fuel Injected

www.dotheton.com/forum/index.php?topic=39120.0

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DoctoRot
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Re: Saving a 1980 750 twin.

22 Feb 2020 08:40

#819689

You think that black stuff was a symptom? I checked the crank for all the things listed in the manual and sent it out to be professionally checked. what else can I do?

'78 1000 Long Term Project
'80 750G
750 Twin Big Bore Track Bike

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Nebr_Rex
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Re: Saving a 1980 750 twin.

22 Feb 2020 18:33 - 22 Feb 2020 18:34

#819708

Looks to me that one rod journal and the center main journal had been hot before assembly.

.

2002 ZRX1200R
81 GPz1100
79 KZ1000st daily ride
79 KZ1000mk2 prodject
78 KZ650sr
78 KZ650b
81 KZ750e
80 KZ750ltd
77 KZ400/440 cafe project
76 KZ400/440 Fuel Injected

www.dotheton.com/forum/index.php?topic=39120.0

.

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Last edit: 22 Feb 2020 18:34 by Nebr_Rex.

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DoctoRot
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Re: Saving a 1980 750 twin.

23 Feb 2020 02:03 - 23 Feb 2020 02:04

#819720

Hmmm that rod journal does look like it got hot. The main bearings all looked OK this time out. it was the opposite rod journal that got burnt up bad this time but both were shot. I’m thinking oil startvation. Gonna check out the oil pump closer. Any other suggestions for the next build?

'78 1000 Long Term Project
'80 750G
750 Twin Big Bore Track Bike

Last edit: 23 Feb 2020 02:04 by DoctoRot.

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