'91 - '03 750 Nighthawk longevity & high mortality parts? Other thoughts. Long.

slmjim

Hopeless Tool Junkie
Joined
Jan 16, 2011
Messages
175
Location
Derby City - Home of The Louisville Slugger
Bike
Which one today...?
Didn't think this would be a good fit in the 'Other Bikes' forum, so here we are. We're all Riders here for the most part, so we particularly value everyone here's input, especially about the changeup thoughts on our stable.

Many of us have (or have had) late model CB750 Nighthawks. This is a long post re: the mental gymnastics we're going through regarding our consideration of changing up our Ridin' stable.

Thinking cap suggested.

We're on multiple fences re: keeping our His n Her pair of '93 Nighthawks we bought new. Recent pic:
Nighthawks.jpg

Both have 70,000+ relatively trouble free, adult touring miles on them. We never wailed on them & they're always garaged. Very well maintained by us. We're Kawasaki Z1 collectors & restoration hobbyists with 40-+ yrs. experience.

We're both over 70. The Lovely Z1BEBE decided to hang up her keys last year, so I pickled her red '93 Nighthawk for long-term storage. My blue '93 Nighthawk needed the carb diaphragms replaced this year, as one was holed. A cheap rack of very-low-mile 750 Nighthawk carbs from fleabay solved that.

I'll continue Ridin'; Joyrides solo on my 750 when the spirit moves me, and Z1BEBE is happy doing the passenger thing on our ST1300A, with a rarel two-up on my Nighthawk, although we'd both like a top box w/ backrest for her.

So, we have two '93 'Hawks, I'm in the autumn of my Ridin' career, and I don't know how many more years I'll be Ridin'. My Ridin' will be split between my Nighthawk, the ST1300A, and whichever of our Kawasaki Z1's we prep for a given season.

Caveat - we're out of room. Garage is full with two vehicles and three bikes, lawn care equipment, and a Honda Hobbit PA50-II moped. The basement shop has six bikes in it. Another one cannot be squeezed into the shop without completely blocking the bike service area. One more bike isn't gonna happen anywhere here at home.


In all cases mentioned below, we keep our collection of Kawasaki Z1's.


Fence 1 - Keep both Nighthawks & prep one alternately each year for maybe, maybe, 2,500 mi. per season. Likely less. This bring up the question of longevity. The CB750 motor is one of the most robust ever manufactured. But, like any machine, there are certain 'high mortality' parts within. "High mortality' is not to be confused with consumable hardware such as spark plugs, chains/sprockets, wheel bearings, brake pads, cables & such.

Upside - We know the model well, know the exact 70,000+ mi. history of our bikes, and have all the docs & most spares we're likely to need.
We have irrational sentimental attachment for our Nighthawks. We've spent 30 yrs. of our 34 years marriage & 70,000 mi. all over two-lane America on them. They mean something to us.
Cost - essentially nil.
Cheap to insure.
Reasonably deep interwebs knowledge base.

Downside - 70,000+ mi. Brings up the longevity Q1 & Q2 questions below.
Not easy to set up for comfy passenger two-up Ridin' + storage due to most accessories NLA.


Q1) We see anecdotal evidence the CB750 Nighthawk motor typically runs trouble-free for 100,000 mi. with good care & maintenance. What sat ye about longevity? Is 100,000 mi. a reasonable estimate based on history of this motor's design?

Q2) What are the (relatively) high-mortality parts in the '91 - '03 750 motor, or the bike in general? Our list so far is:
Turn signals (stalks breaking).
Switchgear, particularly the start switch itself becoming intermittent in the 'RUN' position re: the headlight not always coming on after the motor starts. May be NLA.
Tach. Won't break the bike, but aggravating. Later tachs seem to have solved the problem. We have a late NOS tach on the shelf just in case.
Valve cover gaskets. We replaced both @ ~50,000 mi. or so due to slow weeping developing. Easy.
O-rings at the fuel 'T' & junction pipes. Easy.
Petcock - one failed years ago. Leaked in the 'OFF' position & motor went into hydraulic lock. Rebuild kit failed. Replaced with new OEM. Not exactly high-mortality, but still...


That's about it for our high-mortality list. Any suggestions, parts we've missed?


From here down we're mostly talking to ourselves. It just helps to see things in print sometimes for thoughts to jell. We're most interested in the above. Feel free though, to chime in on how you've managed similar considerations.


Fence 2)
Sell both our 750's & replace with one, nice, much-lower-mileage '91 - '03 Nighthawk. They're out there.
Upside - much newer bike we're very familiar with, & have the service manuals & some spares on the shelf.
Still cheap to insure.
Downside - We have irrational sentimental attachment for our Nighthawks. We've spent 30 yrs. of our 34 years marriage & 70,000 mi. all over two-lane America on them.
Unknown history.
Not easy to set up for comfy passenger two-up Ridin' + storage due to most accessories NLA.
Cost.


Fence 3)
A friend & fellow vintage bike resto hobbyist has a one-owner, low-mile (800 mi. !) 2017 CB1100EX for sale. We sell both 'Hawks, replace them w/ the CB1100 set up w/ top box/backrest.
Upside - Much newer bike. Current OEM parts support. More power than any 750.
Can easily be set up with a top box using currently-available rack & box for backrest & storage for short two-up day / weekend Ridin'.
Known history of this CB1100.
Reasonably deep interwebs knowledge base.

Downside - We start from scratch on parts stock, documentation and a learning curve of a different, much more complex (ABS, fuel injected) bike.
Spoke wheels (tubes) & uncommon tire sizes.
Also, irrational 'Hawk attachment & etc.
More expensive to insure.
Cost++


Fence 4)
Realistically, how many more 3+ week, 2,000+ mi. tours are we likely to do on the ST1300A? The older I get, the taller & heavier it gets. It's a top heavy beast even without a passenger. Her natural parts & single bionic part are making themselves more & more known after a few hours in the saddle. Only stamina issues (so far) I have is typical numbbutt.

Sell the 'Hawks and the ST. Set the CB1100 up w/top box for day / weekend trips.
Upsides & downsides - same as Fence 3. Insurance increase becomes a wash due to fewer bikes.

That's enough for now. The main focus is the longevity considerations & suggestions. Further thoughts welcomed for the talking-to-ourselves portion if the spirit so moves you.

Crossposted to a couple other forums.

Good Ridin'
slmjim & Z1BEBE
 

ardykay54

Russ "NeonMan" Knock
Joined
Apr 27, 2008
Messages
1,157
Age
69
Location
Hopkinton, Iowa
Bike
22 Kaw Z900rs 50 ann
2024 Miles
002718
STOC #
7581
Fence 5.....Give them all to me :biggrin: .....I loved the Nighthawk S (but I was riding a V65 Sabre at the time) and currently ride a 2022 Kaw Z900rs 50th ann. and would love a nice original Z that mine is based on......I know, dream on right.....Love the story...congrats to you and your wife for riding together all those years!! Russ.
 
Joined
Jan 22, 2023
Messages
500
Age
68
Location
woodinville wa
There is no way that you can make the call that it is an " Irrational affection. " My wife and I bought a 2004 ST 1300 and rode it around until we sold it because I went gaga over a Concours, saw it several times on craigslist and bought it back because of a " irrational affection".
I figured that when I can't ride anymore, I am going to roll the ST out to the end of the driveway, pore cement around the tires and put a mailbox on the tail, but it will not leave us while I am still alive. The memories are just too dear to us.
So if irrational is your term, you are not alone, I am betting there is a bunch of us mixed in with the " normal population " Keep them all and wheel them out for a midnight ride.
I am 68 and have 4 bikes now because of this affliction, a 2015 Connie, a 2001 ZRX (because of missing a 2000 ZRX) and of course The ST, the only bike I have that I would even consider parting with is a 2008 KLR. Unfortunately, the memories are starting to build.
 
Joined
Jan 22, 2023
Messages
500
Age
68
Location
woodinville wa
Not always. When we went to the far side of the Mississippi - which I had never seen- I figured that the bike owed me nothing and if it got trashed by anything I was ok. Also the STs almost never do much than have flat tires which makes them the perfect bike for long trips.
We do thorough maintenance on it that diminishes the chance of break downs. Plus, there is Honda shops every where and riding has always been an adventure.
 

Erdoc48

Site Supporter
Joined
Jan 25, 2009
Messages
1,441
Age
59
Location
Myrtle Beach, SC/ Sometimes Colorado
Bike
94/00/04 STs, FSC600
I don’t have a good answer to your dilemma, but just here to say I love the pic of the back to back Nighthawks. I had a black 92 that I owned until 2000 when I got the 2000 ST (I used it for trade in but only put 6700 miles on mine, so someone got a barely used bike). It’s really a tough call what to do- parts for any bike or car won’t be available indefinitely, so you have to do the best you can. Personally, (and this is maybe not the best idea), is to use them as intended, they’re reliable and you know them well. Use them until either they quit or have developed a fatal issue or you have (just kidding on that one). If you try to keep them pristine, it’s going to be a very nice bike for someone else one day. For example, my 94 ABS ST: the ABS system is buggy and no parts are available for it. I disconnected it (yeah, I know, heresy to do such a thing, but I’ve never activated the system when it did work and I’m mostly a fair weather rider) and just ride it like a normal ST (also pulled the bulbs from behind the dash panel so I don’t get the VERY annoying flashing lights due to the faults in the system). All maintenance is current (timing belt and hoses, etc.)- I’m at the point in my life when I’m not getting any younger. I’ll ride them until they fail and maintain them as best as I can (all 3, the 2 STs and the Silverwing)- I’m not planning to buy any more bikes in the future as long as the 3 of these run, and I cycle them so they all get use and not let the fuel, oil, or batteries degrade. They all run perfectly and as long as I can maintain them, I will, and just keep them on the road. Same with my cars- I have zero interest in getting something new when what I have runs fine.
 
Last edited:
Joined
Oct 17, 2022
Messages
414
Age
64
Location
Delta B.C. Canada
I once had a rule , I will keep any vehicle I bought till it makes me call a tow truck three times in one year. Hense I have three Hondas 81,83,and 96 St1100 and a 87 Dodge cargo Van with god knows how many miles on it. Knock on wood have only had the Van exploded the transmission once in the last 17 years,which was annoying because I rebuilt it for a friend as cheep as we could, made sure it wouldn't break the second time around when I owned it. Myself I hate selling Vehicles ,seem the new owners never spend the love and time to keep them in good shape. So yeah my vote would be keep them.
 
Joined
Aug 10, 2015
Messages
2,042
Location
Fort Worth, Texas
Bike
91 ST1100/06 ST1300
These two bikes have well developed Honda engines. As far as assessing remaining life: Perform a compression check and compare that with the values in the repair manual. Do they leak oil? Do they consume oil at an unusual rate?
If they pass these checks, they likely have more life remaining. Hondas usually live a long and productive life if not abused. Not ST 'live long and prosper' mileage but 100k is likely given the care these two seem to have had.
 

Uncle Phil

Site Supporter
Joined
Feb 26, 2007
Messages
11,310
Age
71
Location
In The Holler West Of Nashville, Tennessee
Bike
4 ST1100(s)
2024 Miles
002064
STOC #
698
sentimental ends when it breaks down far from home
I don't know about that .... ;)

Uncle Phil - Newfoundland 2022

I'd say keep what you got and be happy.
Even if you don't ride them much, every time you go out into the garage and see them you are reminded of all the great memories you have with them.
At the end of the day, all you get to keep and take with you are your memories.
 

Erdoc48

Site Supporter
Joined
Jan 25, 2009
Messages
1,441
Age
59
Location
Myrtle Beach, SC/ Sometimes Colorado
Bike
94/00/04 STs, FSC600
I think it may be due to better built engines (more wear resistant metals/ better manufacturing processes) in the past 30 or so years as well as better lubricants, etc. In the past a car engine was on its way out at 70+K miles- now cars and bikes can go several hundred thousand miles (as long as well maintained) without an issue. By the way, what oils are you folks using??? (Yes, just kidding on that last question!). I have a Cadillac SRX (3.6L) and many say oh, the chain will stretch…120K miles later with 5000 mile oil changes and the car runs as new. With the bikes, same thing- I think the ST mileage between oil changes recommendation is 8000 miles- mine never went greater than 4K miles on an oil change. Keep your bikes well lubed and they’ll probably outlast you (and I suspect someone will eventually in MANY years to come inherit my STs that still run perfectly).
 
OP
OP
slmjim

slmjim

Hopeless Tool Junkie
Joined
Jan 16, 2011
Messages
175
Location
Derby City - Home of The Louisville Slugger
Bike
Which one today...?
Thanks everyone! We truly appreciate the relatively objective responses!

Objectivity is something we lack in this situation 'cause we're too close to it. The group wisdom borne of distance is what we were counting on. Bikes as toys for recreational use ultimately are objects wrapped up in emotion, at least for us. If we truly needed bikes for utilitarian transport, we'd likely have gotten different bikes.

Our '93 750's aren't as pristine as the pic makes them look. A bike doesn't go 30 yrs. & cover 70,000+ mi. without a chip, scratch or a little sun fade here & there. They're just mechanically sound, basically bone stock and in VGC at a glance cosmetically. They've been cared for, and about.

If we could add on to the garage we would. Deed restrictions prevent that.

Best Regards all,
and
Good Ridin'
slmjim & Z1BEBE
 
Joined
Jan 22, 2023
Messages
500
Age
68
Location
woodinville wa
I agree that finding parts at a Honda shop may be hit or miss, probably a miss. After market and internet is a good place to look. Many parts are interchange able. I have found ti pretty common that the age of the bike does not mean the parts are available, I had a friend that bought a KTM new and it was down for 6 months waiting for parts. He had the same problem with a Triumph too, although it got the parts sooner.
Breakdowns happen, I had my wife look at my rear tire in Butte and noticed that cord was showing - heat and chip sealing- ending up at a Suzuki dealer for a tire and took it to a Honda dealer to have it put on. Stupid not to be paying attention to the rides condition.
 
Top Bottom