KZ650 Sleeper Build (KZ1000 engine transplant)
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Re: KZ650 Sleeper Build (KZ1000 engine transplant)
06 Jun 2025 17:07
I was able to work on this bike today with only one interruption for a few hours to cut the grass. I was able to prep it for a first start tomorrow and may even get a ride in if its early enough and only if no issues crop up.
I filled the crank case with oil and prefilled the inlet line to the cylinder head along with filling the oil cooler. I fit a pressure gauge to the main gallery to monitor pressure on startup.
I had to make 3 vent elbows and I got the time for each one down to 30 minutes, the first one I did took me 45. The vent tube fitting was time consuming but it looks like it will work. Again, everything is tight toward the top of the frame on this swap.
When I put the coils on I really noticed its tighter than a stock 650 install, but it works.
The only thing stopping me from starting it is the left hand exhaust is currently loose at the head and the muffler mount. I have it loosened to make a small adapter shim bracket to drop the muffler mount and move it inboard. I think it may take me about a hour tomorrow morning. After its assembled I can tighten everything up.
Hopefully there are no surprises.
Tomorrow looks like the last dry day till late next week, the local forecast is for rain Sunday thru Wednesday. If I am gonna ride it and get it broken in sufficiently then my best bet is tomorrow.
I filled the crank case with oil and prefilled the inlet line to the cylinder head along with filling the oil cooler. I fit a pressure gauge to the main gallery to monitor pressure on startup.
I had to make 3 vent elbows and I got the time for each one down to 30 minutes, the first one I did took me 45. The vent tube fitting was time consuming but it looks like it will work. Again, everything is tight toward the top of the frame on this swap.
When I put the coils on I really noticed its tighter than a stock 650 install, but it works.
The only thing stopping me from starting it is the left hand exhaust is currently loose at the head and the muffler mount. I have it loosened to make a small adapter shim bracket to drop the muffler mount and move it inboard. I think it may take me about a hour tomorrow morning. After its assembled I can tighten everything up.
Hopefully there are no surprises.
Tomorrow looks like the last dry day till late next week, the local forecast is for rain Sunday thru Wednesday. If I am gonna ride it and get it broken in sufficiently then my best bet is tomorrow.
1978 KZ650B2 w 1197cc Z1 engine
1977 KZ650B1 w 750cc Spectre engine
1979 KZ650C3 w 831cc Hot Rod engine
1978 KZ650C2 w 762cc DFI project
1977 KZ650C1 stock restoration project
1978 KZ650B2 modified project
1978 KZ650B2 Injected Drag 831cc
1980 Z1 Custom Frame Drag 1327cc
1981 Z50R Honda tow bike
1977 KZ650B1 w 750cc Spectre engine
1979 KZ650C3 w 831cc Hot Rod engine
1978 KZ650C2 w 762cc DFI project
1977 KZ650C1 stock restoration project
1978 KZ650B2 modified project
1978 KZ650B2 Injected Drag 831cc
1980 Z1 Custom Frame Drag 1327cc
1981 Z50R Honda tow bike
The following user(s) said Thank You: sf4t7, Dragbike_Mike, Wookie58, Rolf1976_KZ900
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- TexasKZ
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Re: KZ650 Sleeper Build (KZ1000 engine transplant)
07 Jun 2025 07:28
Good luck!
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
1981 KZ1000 LTD awaiting resurrection
2000 ZRX1100 not ridden enough
www.kzrider.com/11-projects/620336-anoth...uild-thread?start=24
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Re: KZ650 Sleeper Build (KZ1000 engine transplant)
07 Jun 2025 13:31
Hey Injected, what do you use to add the zinc to your oil? I noticed you container is marked, +zinc
Scotty
1974 Z1A
Yoshimura 987
welded Z1 crank
Andrews 1X Cams
Delkevic 4 into 1
Superbike bars
530 conversion
1974 Z1A
Yoshimura 987
welded Z1 crank
Andrews 1X Cams
Delkevic 4 into 1
Superbike bars
530 conversion
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Re: KZ650 Sleeper Build (KZ1000 engine transplant)
07 Jun 2025 16:10 - 07 Jun 2025 16:27Lucas Zinc Plus.Hey Injected, what do you use to add the zinc to your oil? I noticed you container is marked, +zinc
1978 KZ650B2 w 1197cc Z1 engine
1977 KZ650B1 w 750cc Spectre engine
1979 KZ650C3 w 831cc Hot Rod engine
1978 KZ650C2 w 762cc DFI project
1977 KZ650C1 stock restoration project
1978 KZ650B2 modified project
1978 KZ650B2 Injected Drag 831cc
1980 Z1 Custom Frame Drag 1327cc
1981 Z50R Honda tow bike
1977 KZ650B1 w 750cc Spectre engine
1979 KZ650C3 w 831cc Hot Rod engine
1978 KZ650C2 w 762cc DFI project
1977 KZ650C1 stock restoration project
1978 KZ650B2 modified project
1978 KZ650B2 Injected Drag 831cc
1980 Z1 Custom Frame Drag 1327cc
1981 Z50R Honda tow bike
Last edit: 07 Jun 2025 16:27 by Injected. Reason: pic
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Re: KZ650 Sleeper Build (KZ1000 engine transplant)
07 Jun 2025 16:23 - 07 Jun 2025 16:33
Today was a mixed bag, it took me twice as long as I figured to fabricate that shim to drop and suck in the LH muffler. I did get the bike started and everything was good, but when I went to set the timing it started running on 2 cylinders only minutes after getting the barrel warm.
I also had a oil leak from a hose end fitting I only had hand tightened, a complete screw up on my part. It was the inside lower block (return hose) so it sent oil down that little gap next to the starter cover, then under the bike down the trans cover! That took me a bit to clean up and sort.
I discovered no spark on 1&4 and rich on 2&3 (pilot air adjustment?) so I swapped wires around and found the coil for 1&4 had just died on me. Luckily my other bike has a set of Dyna Green coils on it that are good. I then robbed them from it, but by the time I did that and removed those Acell coils the wife was calling me in for dinner.
We will see how I get on tomorrow, but already have some mid day plans so it might be tricky to work on it.
I will try to post some pics when I catch my breath. I did make a couple of videos, but I don't want to post them to You Tube until after the swap meet.
I also had a oil leak from a hose end fitting I only had hand tightened, a complete screw up on my part. It was the inside lower block (return hose) so it sent oil down that little gap next to the starter cover, then under the bike down the trans cover! That took me a bit to clean up and sort.
I discovered no spark on 1&4 and rich on 2&3 (pilot air adjustment?) so I swapped wires around and found the coil for 1&4 had just died on me. Luckily my other bike has a set of Dyna Green coils on it that are good. I then robbed them from it, but by the time I did that and removed those Acell coils the wife was calling me in for dinner.
We will see how I get on tomorrow, but already have some mid day plans so it might be tricky to work on it.
I will try to post some pics when I catch my breath. I did make a couple of videos, but I don't want to post them to You Tube until after the swap meet.
1978 KZ650B2 w 1197cc Z1 engine
1977 KZ650B1 w 750cc Spectre engine
1979 KZ650C3 w 831cc Hot Rod engine
1978 KZ650C2 w 762cc DFI project
1977 KZ650C1 stock restoration project
1978 KZ650B2 modified project
1978 KZ650B2 Injected Drag 831cc
1980 Z1 Custom Frame Drag 1327cc
1981 Z50R Honda tow bike
1977 KZ650B1 w 750cc Spectre engine
1979 KZ650C3 w 831cc Hot Rod engine
1978 KZ650C2 w 762cc DFI project
1977 KZ650C1 stock restoration project
1978 KZ650B2 modified project
1978 KZ650B2 Injected Drag 831cc
1980 Z1 Custom Frame Drag 1327cc
1981 Z50R Honda tow bike
Last edit: 07 Jun 2025 16:33 by Injected. Reason: info
The following user(s) said Thank You: sf4t7, Wookie58, Rolf1976_KZ900, kimchella
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Re: KZ650 Sleeper Build (KZ1000 engine transplant)
07 Jun 2025 18:03 - 07 Jun 2025 18:04
I also had a small oil leak on both rear cam end plugs, one side worse than the other, that damn RTV! I cinched down the bolts so hoping the leaks subside, if not I will need to redo those two.
Here is what I had to do without running out to buy material, scrap bin to the rescue!
I did not have a solid piece so used what I could scrounge, it works for now and got the mufflers "closer".
Its just a bit off, so one day I will make another to come closer but order the material to machine it out of a solid piece.
The idea works and it gets the job done.
Here is what I had to do without running out to buy material, scrap bin to the rescue!
I did not have a solid piece so used what I could scrounge, it works for now and got the mufflers "closer".
Its just a bit off, so one day I will make another to come closer but order the material to machine it out of a solid piece.
The idea works and it gets the job done.
1978 KZ650B2 w 1197cc Z1 engine
1977 KZ650B1 w 750cc Spectre engine
1979 KZ650C3 w 831cc Hot Rod engine
1978 KZ650C2 w 762cc DFI project
1977 KZ650C1 stock restoration project
1978 KZ650B2 modified project
1978 KZ650B2 Injected Drag 831cc
1980 Z1 Custom Frame Drag 1327cc
1981 Z50R Honda tow bike
1977 KZ650B1 w 750cc Spectre engine
1979 KZ650C3 w 831cc Hot Rod engine
1978 KZ650C2 w 762cc DFI project
1977 KZ650C1 stock restoration project
1978 KZ650B2 modified project
1978 KZ650B2 Injected Drag 831cc
1980 Z1 Custom Frame Drag 1327cc
1981 Z50R Honda tow bike
Last edit: 07 Jun 2025 18:04 by Injected. Reason: sp
The following user(s) said Thank You: Nessism, Dragbike_Mike, Wookie58, Rolf1976_KZ900
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Re: KZ650 Sleeper Build (KZ1000 engine transplant)
08 Jun 2025 08:22
Just tested spark out there on that engine, fat blue spark on both coils! 
Have to stop because I have a prior engagement, but will get on it when I get back.

Have to stop because I have a prior engagement, but will get on it when I get back.
1978 KZ650B2 w 1197cc Z1 engine
1977 KZ650B1 w 750cc Spectre engine
1979 KZ650C3 w 831cc Hot Rod engine
1978 KZ650C2 w 762cc DFI project
1977 KZ650C1 stock restoration project
1978 KZ650B2 modified project
1978 KZ650B2 Injected Drag 831cc
1980 Z1 Custom Frame Drag 1327cc
1981 Z50R Honda tow bike
1977 KZ650B1 w 750cc Spectre engine
1979 KZ650C3 w 831cc Hot Rod engine
1978 KZ650C2 w 762cc DFI project
1977 KZ650C1 stock restoration project
1978 KZ650B2 modified project
1978 KZ650B2 Injected Drag 831cc
1980 Z1 Custom Frame Drag 1327cc
1981 Z50R Honda tow bike
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Re: KZ650 Sleeper Build (KZ1000 engine transplant)
08 Jun 2025 15:32 - 08 Jun 2025 15:33
I did get back working on this today, got it started and I am working on tuning it. Re-torqued the head, it needed it just after that first start before the coils got installed.
It cold started with no issues full choke on the starter motor, ran OK once I got it warmed and set the idle but it started cutting out and died. Its a fricken BEAST, revved it up about 4K and kids on the street ran for cover
After that it was a bear to start, ran my battery down (older AGM) so tried kicking it and just about broke my leg! Put the battery back on trickle charger and did some other stuff, but I think I will try again tomorrow. Hamstring is now tweaked
I had the pilot air screws mostly closed at 1/8 turn (it started that way) but put them at 1/4 turn to see if that helps any.
Cam cover is still weeping, will need to lift it and redo the RTV... pain in the arse!
If I can't get it sorted by Wednesday the Touring bike needs to be prepped to ride to the swap meet.
It cold started with no issues full choke on the starter motor, ran OK once I got it warmed and set the idle but it started cutting out and died. Its a fricken BEAST, revved it up about 4K and kids on the street ran for cover

After that it was a bear to start, ran my battery down (older AGM) so tried kicking it and just about broke my leg! Put the battery back on trickle charger and did some other stuff, but I think I will try again tomorrow. Hamstring is now tweaked
I had the pilot air screws mostly closed at 1/8 turn (it started that way) but put them at 1/4 turn to see if that helps any.
Cam cover is still weeping, will need to lift it and redo the RTV... pain in the arse!
If I can't get it sorted by Wednesday the Touring bike needs to be prepped to ride to the swap meet.
1978 KZ650B2 w 1197cc Z1 engine
1977 KZ650B1 w 750cc Spectre engine
1979 KZ650C3 w 831cc Hot Rod engine
1978 KZ650C2 w 762cc DFI project
1977 KZ650C1 stock restoration project
1978 KZ650B2 modified project
1978 KZ650B2 Injected Drag 831cc
1980 Z1 Custom Frame Drag 1327cc
1981 Z50R Honda tow bike
1977 KZ650B1 w 750cc Spectre engine
1979 KZ650C3 w 831cc Hot Rod engine
1978 KZ650C2 w 762cc DFI project
1977 KZ650C1 stock restoration project
1978 KZ650B2 modified project
1978 KZ650B2 Injected Drag 831cc
1980 Z1 Custom Frame Drag 1327cc
1981 Z50R Honda tow bike
Last edit: 08 Jun 2025 15:33 by Injected. Reason: sp
The following user(s) said Thank You: Nessism, sf4t7, Gdizard, Wookie58
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Re: KZ650 Sleeper Build (KZ1000 engine transplant)
Yesterday 14:42
Got out there today and started it with no issues, it felt sluggish (rich) so I warmed it up without the fan on to get some heat into it. Put the Color Tune plug on it and found it Orange (rich), adjusted the air screw out until it started to turn blue but it was not a true blue sort of had white thru it. Plugs are fluffy sooty black.
Killed it and found the screw was backed out almost two full turns which I know is not correct. These air screws has a cross hole in them and should only ever be out less than 1 full turn or the hole is shut off. That indicates a too rich pilot jet. Not sure if messing with the main air jet would help. Might just drop down to a #20 pilot, its drinking a lot of gas
Here are my carb specs so far :
VM33 Smooth Bores
custom 4 into 2 exhaust w stock 750 air box/paper filter
slide cutaway = 1.5 (stock)
jet needle = #6DJ30 (stock)
needle clip = #3 (middle)
needle jet = #O-6 (stock)
main air jet = #1.2
pilot jet = #25
float level = 22.5 mm
pilot air screw 1/2 turn out
main jet = #127.5
new choke plunger seals
When I shut it off found that cylinder #1 was not running, not sure but I think a valve is hanging opened as there was fuel out the exhaust gasket. Went to start it to run the gas out of the line and the battery died.
At this point I realized there was no way I was going to ride this anywhere!
Pretty sure I need to do a compression check to see where I am at, even cold will do for now. Pretty sure I need to investigate the purchase of a new stronger battery. Current battery is a 4 year old 210CCA AGM. GPZ1100 starter seems to be fine as so does the starter clutch.
Pretty sure I need to fix the cam end plug leaks. Engine diaper material is only for the garage.
I swapped out the Dyna 3 for a new Dyna S clone, the Dyna green coils are better and I like the longer Taylor wires because they are needed to go around the cam cover at the back. If the wires lay on the cam cover they will be right on the bottom of the gas tank! The wire for #2 plug needs to be longer so I am getting some bulk Taylor wire from a local speed shop, will reuse my ends.
Parking this one for now till I have time to giving it a good going over, don't want to rush it.
Killed it and found the screw was backed out almost two full turns which I know is not correct. These air screws has a cross hole in them and should only ever be out less than 1 full turn or the hole is shut off. That indicates a too rich pilot jet. Not sure if messing with the main air jet would help. Might just drop down to a #20 pilot, its drinking a lot of gas

Here are my carb specs so far :
VM33 Smooth Bores
custom 4 into 2 exhaust w stock 750 air box/paper filter
slide cutaway = 1.5 (stock)
jet needle = #6DJ30 (stock)
needle clip = #3 (middle)
needle jet = #O-6 (stock)
main air jet = #1.2
pilot jet = #25
float level = 22.5 mm
pilot air screw 1/2 turn out
main jet = #127.5
new choke plunger seals
When I shut it off found that cylinder #1 was not running, not sure but I think a valve is hanging opened as there was fuel out the exhaust gasket. Went to start it to run the gas out of the line and the battery died.
At this point I realized there was no way I was going to ride this anywhere!
Pretty sure I need to do a compression check to see where I am at, even cold will do for now. Pretty sure I need to investigate the purchase of a new stronger battery. Current battery is a 4 year old 210CCA AGM. GPZ1100 starter seems to be fine as so does the starter clutch.
Pretty sure I need to fix the cam end plug leaks. Engine diaper material is only for the garage.
I swapped out the Dyna 3 for a new Dyna S clone, the Dyna green coils are better and I like the longer Taylor wires because they are needed to go around the cam cover at the back. If the wires lay on the cam cover they will be right on the bottom of the gas tank! The wire for #2 plug needs to be longer so I am getting some bulk Taylor wire from a local speed shop, will reuse my ends.
Parking this one for now till I have time to giving it a good going over, don't want to rush it.
1978 KZ650B2 w 1197cc Z1 engine
1977 KZ650B1 w 750cc Spectre engine
1979 KZ650C3 w 831cc Hot Rod engine
1978 KZ650C2 w 762cc DFI project
1977 KZ650C1 stock restoration project
1978 KZ650B2 modified project
1978 KZ650B2 Injected Drag 831cc
1980 Z1 Custom Frame Drag 1327cc
1981 Z50R Honda tow bike
1977 KZ650B1 w 750cc Spectre engine
1979 KZ650C3 w 831cc Hot Rod engine
1978 KZ650C2 w 762cc DFI project
1977 KZ650C1 stock restoration project
1978 KZ650B2 modified project
1978 KZ650B2 Injected Drag 831cc
1980 Z1 Custom Frame Drag 1327cc
1981 Z50R Honda tow bike
The following user(s) said Thank You: Nessism, MFP-Joe, SWest, Wookie58, kimchella
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Re: KZ650 Sleeper Build (KZ1000 engine transplant)
Today 05:18
A couple of videos I posted of this bike :
1978 KZ650B2 w 1197cc Z1 engine
1977 KZ650B1 w 750cc Spectre engine
1979 KZ650C3 w 831cc Hot Rod engine
1978 KZ650C2 w 762cc DFI project
1977 KZ650C1 stock restoration project
1978 KZ650B2 modified project
1978 KZ650B2 Injected Drag 831cc
1980 Z1 Custom Frame Drag 1327cc
1981 Z50R Honda tow bike
1977 KZ650B1 w 750cc Spectre engine
1979 KZ650C3 w 831cc Hot Rod engine
1978 KZ650C2 w 762cc DFI project
1977 KZ650C1 stock restoration project
1978 KZ650B2 modified project
1978 KZ650B2 Injected Drag 831cc
1980 Z1 Custom Frame Drag 1327cc
1981 Z50R Honda tow bike
The following user(s) said Thank You: Wookie58
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