Design Disadvantages of the CB1100

C

calamarichris_imp

Running like a top
Thread starter
Everything designed by the hand of man has its advantages and disadvantages. As PeeWee Herman says, "Everyone I know in life has a big but(t)...":
~Harleys sound great and you never have to adjust the valves, BUT they're slow, inefficient, and the rear cylinder does not get as much cooling air as the front. (That, and you have to ride everywhere with a serious scowl of determination on your face, as if you are on your way to commit your third-strike felony.)
~Crotch-rockets are light & fast, but the cylinders are bored into the top half of the crankcase (disposabike) and being stuck behind an RV on a twisty road sucks even worse when you're on one of them.
~Vertical Twins (one piston goes up while the other goes down) can rev higher and are generally more efficient overall, but they get lumpy and weak at low rpm.
~Parallel twins (both pistons rise & fall together) are terrific at lower rpm and have a sweet, balanced sound, but they create a pressure maelstrom in the crankcase which inhibits higher rpm power.

So what are some of the advantages and disadvantages of the CB11's engine? Not interested in the smile-on-your-face while riding on a sunny day advantages. Every design has its disadvantages, what are the CB11's?
Heavy weight?
Plastic bits?
Throttle governor?
Less cooling air for #2 & 3 cylinders? (Are they jetted identically with #1 & 4, or richer/cooler?)
 
Well a disadvantage would have to be the width and weight of the engine. It a big mill. It doesn't produce a lot of horsepower or torque relatively speaking, although it has plenty of both for it's intended purpose.

It's frame is basic and heavy.

It doesn't have perfect primary or secondary balance so it does produce some vibration, particularly at higher rpms, but compared to singles, most twins, or triples it's very smooth.

It is so under stressed that it should run virtually forever.

But from a purely personal observation, it is a beautiful power plant, and motorcycle, and it's whole is greater than the sum of it's parts. It is a very satisfying motorcycle to ride and to look at.
 
Con: Valves require regular checking and possible adjustment. Would've preferred the proven and dead reliable hydraulic system that served so well in many Honda Nighthawks. Redline is under 10,000 rpm, so it certainly technically feasible.

Pro: Pretty damn decent fuel economy on regular gas for an 1140cc 4-cyl pulling 540 lbs.
 
Thread starter
I'm actually a fan of the robustness and quiet running of the shim-under bucket design, and don't mind going in every 7500 miles or so, to make sure everything's happy in there, but to each his own. What is the valve adjustment interval on the CB11?

What kind of MPG are you pulling down?

Full disclosure: I do not yet own one, but am giving serious thought to trading in my EX50o dog-taxi for one. (It's not my only bike, just the one I'm thinking of trading in.)
 
8000 on the valve adjustments

50 plus mpg as high as 56 mpg, lowest has been 48 on first tank
 
Thread starter
8000's not too bad. I presume an adjustment means lifting the cams?

If any of you guys are thinking of adjusting your own valves for the first time, it's a neat process. Here's my little online primer for adjusting valves on Kawasaki's mighty ZX9R. (clicky) You'll still want to get the Honda Factory manual before tackling the job on your CB's, but it gives you an idea.
One advantage to this bike is you don't have to drain any coolant, disconnect any radiators, or worry about getting any little O-rings on the coolant plumbing misaligned. Ought to save at least an hour on the job.

Just made me think of another example of advantage/disadvantage:

Kawasakis are known for having comparatively steep cams, which mean excellent top-end power. But those tall cams require stiff valve springs to avoid valve float at higher rpm, which means more valve seat & seal wear. If you stay on top of the maintenance, they still do pretty well.
There used to be a joke going around about Kawasakis when I bought that 9R 12 years ago:
"What do you call a Kawasaki with a quiet top end?"
"A two-stroke."

My old 9R does sound a little clattery when cold, but I've been more than meticulous with the maintenance over the years and she still purrs like a kitten when warm, (and still has a terrifyingly brutal hit at 9000rpm that still scares me on public roads.)
 
Good night..just read all 9 pages of your valve adj procedure. Jeezalou that's complicated. Would have taken another 9 pages to put it back together I assume.

That is why hydraulic valves make a lot of sense.
 
Thread starter
I'm a little more thorough than your average dealership tech. If you do a good job, it ain't gonna be finished in 3 hours, like they charge you for.
I've drunken with a few techs who don't even bother with a torque wrench. Even if you pay the dealership $90 an hour and tip him well, that guy with the facial piercings still ain't gonna put the love & Q-tips into your baby that you would.

Hydraulic valves have more working parts, and are therefore more prone to breakage & wear over the long haul. Yeah it's a lot of work, but there's something hugely satisfying about shaking hands with the magic genie inside your engine that magically thrusts you hundreds of feet per second through our thick, gooey atmosphere. (I'm also a cyclist, so I have an appreciation for this magic.) Do you trust a system over the long haul, or do you trust yourself?
The ferret_imp said:
Well a disadvantage would have to be the width and weight of the engine. It a big mill. It doesn't produce a lot of horsepower or torque relatively speaking, although it has plenty of both for it's intended purpose.

It's frame is basic and heavy.

It doesn't have perfect primary or secondary balance so it does produce some vibration, particularly at higher rpms, but compared to singles, most twins, or triples it's very smooth.

It is so under stressed that it should run virtually forever.

But from a purely personal observation, it is a beautiful power plant, and motorcycle, and it's whole is greater than the sum of it's parts. It is a very satisfying motorcycle to ride and to look at.
Click to expand...
I said NO SMILE ON YOUR FACE/sunny day sentimentality, yo!

Pretty hard to do understressed without going big & heavy. That's an acceptable trade compared to lightweight and no power, IMO.

I'm surprised it has any vibration. I-4's are supposed to be basically balanced. My 9R doesn't have any balance shafts or counterbalancers, and that thing (to borrow a Ducatisti-ism) has all the character of an electric motor. (A 130hp electric motor.) I chuckle at all these Yamaha I4's that have unbalanced engines, so they sound better, like Rossi's GP bike. But there's no motorcycle engine in the world as efficient as a pre-Rossi/V5, balanced inline-4.
If I'm wrong, tell me which layout is more efficient and why.

Vibration? Really? What did you ride before you got your CB?
 
The actually engineered in the vibration to harken back to the old days when balancing an engine (properly) was totally labor intensive and would triple the cost of the bike if done correctly.
Something about changing the cam spec somehow, but I can't remember the specifics and I'm too lazy at this very moment in time to look it up.
 
Thread starter
So Honda took some QC shortcuts to make the bike more authentically retro? That's pretty discouraging, but I appreciate your candor. Let me know when the laziness abates and you've got some links.
 
I keep hearing that legend but I don't believe it. A more believable reason for the different valve timing of #2 & 3 is the theory that it helps the cooling of the center 2.
 
Thread starter
"Intentionally staggered intake-valve timing gives it a slightly rougher feel reminiscent of the earlier fours,"...
Jesus' trousers. :( It's right there.
An intentionally retarded engine. :( Color me blue, that was a dumb thing for Honda to do. If I wanted less efficiency, I'd buy a Harley and pretend to be an outlaw.
They could have omitted a spark plug for those who want the reminiscence of earlier fours, so that those of us who want smoothness/efficiency/long service life could remedy it by paying extra for a custom spark plug.
I wonder what kind of mileage, or what kind of power these bikes would make if they weren't hobbled by such engineering/marketing. :(

Any chance this is just some journalist taking a little too much poetic license?
Honda completely screwed the pooch with the VTR1000 Superhawk IMO, but this is almost as bad. :(
Rougher feel = less smoothness = shorter and less efficient lifespan.
Damn. I haven't been this crestfallen since BMW-USA's reaction to the surging issue. :(

There really is no perfect design.
 
calamarichris_imp said:
Everything designed by the hand of man has its advantages and disadvantages. As PeeWee Herman says, "Everyone I know in life has a big but(t)...":
~Harleys sound great and you never have to adjust the valves, BUT they're slow, inefficient, and the rear cylinder does not get as much cooling air as the front. (That, and you have to ride everywhere with a serious scowl of determination on your face, as if you are on your way to commit your third-strike felony.)
~Crotch-rockets are light & fast, but the cylinders are bored into the top half of the crankcase (disposabike) and being stuck behind an RV on a twisty road sucks even worse when you're on one of them.
~Vertical Twins (one piston goes up while the other goes down) can rev higher and are generally more efficient overall, but they get lumpy and weak at low rpm.
~Parallel twins (both pistons rise & fall together) are terrific at lower rpm and have a sweet, balanced sound, but they create a pressure maelstrom in the crankcase which inhibits higher rpm power.

So what are some of the advantages and disadvantages of the CB11's engine? Not interested in the smile-on-your-face while riding on a sunny day advantages. Every design has its disadvantages, what are the CB11's?
Heavy weight?
Plastic bits?
Throttle governor?
Less cooling air for #2 & 3 cylinders? (Are they jetted identically with #1 & 4, or richer/cooler?)
Click to expand...
Of course, the advantages of and disadvantages of those things designed by the hand of man pale in comparison to the advantages and disadvantages of man himself. In this case, I'd ask what exactly is it that you're looking for from this engine? Only by answering this question can you begin to address advantages and disadvantages when it comes to the CB1100. (i.e. If your not inclined to ride over 110 mph, then the speed-limiter isn't a disadvantage.)

How many Harley owners are concerned about riding overly fast or how much cooling their rear cylinder is getting compared to the front? Chances are it's a very small percentage. Conversely, what percentage of supersport class bike owners are concerned with how sedately their bike cruises when not being pushed or even have thoughts of long-term ownership? How many guys with twins are really worried about the lack of low-end or high-end power of their respective machines? For most, these disadvantages from a purely technical sense aren't disadvantages at all. Those who consider such items as disadvantages are more than likely those who didn't properly consider their own needs.

In my mind, you have to have something to measure against (in this case the desired use for the bike) to try and identify the respective disadvantages. My needs are bound to be different from yours and therefore what I see as an advantage or disadvantage might vary quite a bit from you, especially if your not concerned about the "smile-on-your-face while riding on a sunny day" type of stuff. It's honestly hard for me give you much feedback as one of my actual requirements was for a bike that I got as much enjoyment from looking at it when I was off of the bike as I did from actually riding it. What can I say, I went to school for engineering and ended up working for a number of years as a graphic designer, I'm a bit skewed.

I quickly identified two issues with the bike that were a disappointment to me. Thus far these are my only real gripes:

1.) The weight of the bike when moving it around in the garage and so forth. Obviously this can't be chalked up just to the engine, but the size of the engine surely plays a part in this. I'll simply live with this and won't be addressing it further. Once the bike starts rolling, however slowly, I'm good with it.

2.) The tone of the factory exhaust. Simply too peaceful for me. I'm not a fan of loud exhausts, but I do like an exhaust note with a bit of soul if you will. I addressed this by adding a slip-on exhaust from Staintune and I've been very pleased with the result.

Some issues, such as engine longevity, will only be answered in time. People can theorize as much as they want, but until enough units have withstood the test of time and miles (or not), theories will remain just that.

At this point, I can't tell you much at this point about working on the bike. That will change over time as I plan on doing pretty much everything on my own. I'm no expert mechanic by any means, but I've learned a heck of a lot by doing all of my own work on my Hawk GT (the only other street bike I've ever owned) over the past 7 years, and I like the feeling of satisfaction that I've received from that experience. No reason to change things up at this point. If I fail at something, then I can pay somebody else, but until that time comes, I'll keep turning my own wrenches.

With all that said, as mentioned, my Hawk GT is the only other street bike I've ever owned. A 647cc V-Twin and an 1140cc Inline Four don't exactly make for a wealth of experience. Therefore, for better or worse, my expectations are probably far different than many guys here who have owned a wealth of bikes over the years and have a lot more comparables to draw from.
 
From the Factory Service manual...

Intake timing for cylinders 1 and 2:
opens at 5 degrees ATDC, closes 28 degrees ABDC

Intake timing for cylinders 3 and 4:
opens at 5 degrees ATDC, closes 38 degrees ABDC

Exhaust timing for cylinders 1,2,3 and 4:
opens 42 degrees BBDC, closes 10 degrees BTDC

Maybe this is done to broaden the powerband of the engine as opposed to doing so for nostalgic reasons? At any rate, I'll take my chances, choosing to side with Honda's engineering team.
 
WOW.....I just got what I payed for. And if I had the money to bye any other bike I wanted I would regardless of mark.
But there is so many bikes that have gone before, La Verda, Vincent's, Some beautiful Triumphs, Nortons,
I'm not a thrasher of bikes but the CB 1100 is a gentleman's motorcycle not a rev head's. There plenty of bikes out there to choose from for whatever need. I you have a CB 1100 and don't think is up to your standard it's not the bikes fault you have chosen the wrong bike for your need or use.
 
Guth_imp said:
From the Factory Service manual...

Intake timing for cylinders 1 and 2:
opens at 5 degrees ATDC, closes 28 degrees ABDC

Intake timing for cylinders 3 and 4:
opens at 5 degrees ATDC, closes 38 degrees ABDC

Exhaust timing for cylinders 1,2,3 and 4:
opens 42 degrees BBDC, closes 10 degrees BTDC

Maybe this is done to broaden the powerband of the engine as opposed to doing so for nostalgic reasons? At any rate, I'll take my chances, choosing to side with Honda's engineering team.
Click to expand...
From a previous post:
this is a misprint in the shop manual, happens all the time with a non procedure specs.if this was a service check procedure red flags would have flown very early from feedback from service engineering and field service techs.i'm sure it will be corrected by next shop manual printing if Honda knows about it.
correct spec should read-
intake timing for cyl #1 and#4 opens at 5 degrees atdc, closes 28 degrees abdc
intake timing for cylinders #2 and #3 opens 5 degrees atdc, closed 38 degrees abdc
Paul. Sr.Tech. Specialist, American Honda Motor Co.Inc= Retired.
 
You must log in or register to reply here.

Similar threads

Cormanus
CB1100: A little history by the Ferret
Replies
0
Views
347
Cormanus
Cormanus
G
NC750XD: Initial review ...
3 4 5
Replies
90
Views
8K
GoldOxide_imp
G
Back
Top