KZR's Bikes of the Month for 2024

'81 kz750h / '77 kz650b swap

More
02 Sep 2019 15:04 - 02 Sep 2019 15:20 #810249 by cbewley
'81 kz750h / '77 kz650b swap was created by cbewley
Been about 7 years since my last post on this forum. Long story short, my 750 ran great for years, leaked oil, then died. And still leaked oil from everywhere. Took her down to a rolling frame 2 years ago and there she sat.
Recently I scored a pretty decent 77 650b from a friend on the cheap (parts bike). Carbs were off, but everything else appears to be there and in good shape. Gave the carbs a once over, got a battery, fixed ignition switch, fixed the points to get spark, and got it to run on carb cleaner. I managed to have it idle on gas for about 15 seconds. Now I pulled the carbs off again to actually clean them. I'm posting here to try and keep myself motivated. End goal is to have the 77 motor in the 81 frame.

750 as my daily ride


750 surgery



650


'81 kz750H with '77 650B motor
Last edit: 02 Sep 2019 15:20 by cbewley.

Please Log in or Create an account to join the conversation.

More
12 Sep 2019 13:22 #810763 by cbewley
Replied by cbewley on topic '81 kz750h / '77 kz650b swap
Removed the carbs to give them a better cleaning and discovered one pilot jet is missing. I just placed an order for one, so I will have to wait until next week to see if it wants to run any better.

'81 kz750H with '77 650B motor
Attachments:

Please Log in or Create an account to join the conversation.

  • Scirocco
  • Offline
  • Premium Member
  • Never change a running system
More
12 Sep 2019 15:12 #810765 by Scirocco
Replied by Scirocco on topic '81 kz750h / '77 kz650b swap
Be sure the choke (enricher) passages and jets are not clogged, they need to be cleaned too.

Attachments:
The following user(s) said Thank You: Nessism

Please Log in or Create an account to join the conversation.

More
13 Sep 2019 01:53 #810792 by cbewley
Replied by cbewley on topic '81 kz750h / '77 kz650b swap

Scirocco wrote: Be sure the choke (enricher) passages and jets are not clogged, they need to be cleaned too.


I did clean the passages in the float bowls. One or two were pretty well jammed up. Did my best to clean the jets you pointed out, but not sure how to remove them. I appreciate the tips, I'm learning as I go here.

'81 kz750H with '77 650B motor

Please Log in or Create an account to join the conversation.

  • Scirocco
  • Offline
  • Premium Member
  • Never change a running system
More
13 Sep 2019 02:29 #810793 by Scirocco
Replied by Scirocco on topic '81 kz750h / '77 kz650b swap
The Jet tubes for the enricher cricuit are press fit into the carb Body, no way to remove them without any damage!
Try to clean the jet bore with a thin fishing line Nylon.

Please Log in or Create an account to join the conversation.

  • SWest
  • Offline
  • Sustaining Member
  • 10 22 2014
More
13 Sep 2019 07:52 #810802 by SWest

Please Log in or Create an account to join the conversation.

More
13 Sep 2019 13:06 - 13 Sep 2019 13:39 #810810 by TexasKZ
Replied by TexasKZ on topic '81 kz750h / '77 kz650b swap
Less than $1 at a local music store.


1982 KZ1000 LTD parts donor
1981 KZ1000 LTD awaiting resurrection
2000 ZRX1100 not ridden enough

www.kzrider.com/11-projects/620336-anoth...uild-thread?start=24
Attachments:
Last edit: 13 Sep 2019 13:39 by SWest.

Please Log in or Create an account to join the conversation.

More
13 Sep 2019 14:35 #810818 by cbewley
Replied by cbewley on topic '81 kz750h / '77 kz650b swap
Thanks guys, good to know. Fortunately enough I have a box of ernie balls laying around. I can play a thing or two :whistle:

'81 kz750H with '77 650B motor

Please Log in or Create an account to join the conversation.

More
02 Jul 2020 12:14 #829616 by cbewley
Replied by cbewley on topic '81 kz750h / '77 kz650b swap
Well, so much for posting updates to keep motivated.
I did end up getting the bike to run well enough to proceed with the swap. Didn't do much to it over the winter, but hit it hard this spring.
She's got a bunch of new, customized, and swapped parts from the 650. But I still have a decent amount on the to-do list.

She runs and rides ok, but There is definitely a tuning issue to address. I'm still doing the trial and error with the jetting. There's more research to do before I start asking for help on that (haha).

Aside from tuning, the to-do list consists of addressing the front fork seals & paint, trimming front turn signal posts to align headlight, mount to frame and reupholster the potato sack seat, rebuild petcock, and pulling dent from the gas tank and giving it a paint job. And I'm sure I am missing a few things.
Here it is currently:

'81 kz750H with '77 650B motor
Attachments:

Please Log in or Create an account to join the conversation.

Powered by Kunena Forum

If you like KZR Please consider making a donation. Thank you.

KZRider is free, but not without cost.

Please consider chipping in a few bucks to help cover the cost of running the KZR servers.