Newbie ? 79 - 80

[1jamesbond]

Hi guys,

I could make this post 5 pages long but that would be boring - so here goes. I had a LOT of motorcycles in the 70's and 80's, did some road racing, the whole 9 yards. Retired in the late 80's just as the chassis and tyre technology was catching up to the horsepower. Good thing too or I probably wouldn't be alive to write this. BTW that's more due to lack of natural talent than anything else. So that's the history portion of my post..

I have a distinct memory of riding a friends 79 Red CBX in 1979 when they first came out and I remember the wonderful engine sound and how huge the bike felt ( at the time my street bike was a modified 900cc BMW). I was blown away by the technology and the 6 cylinder engine, but at the time, I was into riding very fast especially in corners and the CBX seemed so big and heavy.

Fast forward 35 years or so and I don't give a damn about riding fast anymore, in fact that's the last thing I want to do on the street. So now from a nostalgic perspective the CBX has a huge appeal to me. Other choices would be BMW R90 S or Ducati 900SS, maybe a Z1...

Sorry for a long winded intro. Here's my questions. What are the major differences between 1979 and 1980 MY bikes? Did the swing arm pivot get improved for 80, bearings and size? Was the motor de -tuned with different ignition advance, cams, cam timing, carburetor jetting? If so, what does it take to liven up a 1980 bike to perform like a 79? I know the wheels went from silver to black, were they made any better? I seem to remember back in the day, stories of com star wheel rivets coming lose. Were the fork tube sizes the same? I dislike the ape hanger style bars of the 79 did they get lowered in 80, or is that totally dependent on the sports kit option. I wouldn't buy a CBX with the idea of hot rodding it. I don't see the point, but I would like to have a period correct " euro style" set up.

Many thanks in advance for your patience with my questions.

Simon

[daves79x]

Welcome Simon!

Your questions would take pages to answer thoroughly also. I'll hit the high points. There are well over 100 differences between the '79 and '80 models. Far too many to list. Major ones are the improved swingarm pivot and improved (but still 35mm) front fork. Wheels are just reversed, blacked out Comstars, with the rear being a bit wider. The engine is 'detuned' a bit with different cams and carbs. Pipes have different internal baffling also, but that's a moot point anymore as original 469 ('80 designation) pipes are pretty rare. The '80 has a tail trunk. The '79 came in red or silver and the '80s were the same red or black. Us models of both years came with high bars and both had the sport kit (low bars and rearsets) option. Other markets came standard with the low bars. I consider the '80 to be a more complete incarnation of what the CBX should be, but at this stage, as you say, we don't really flog these too much and a nice example of either year would suit you fine, I'm sure. Hang around here and I think you'll get the idea of what these are all about and also search the archives. Lots of good info there. I sent you a PM also.

Dave

[EMS]

Hi guys,

what does it take to liven up a 1980 bike to perform like a 79?

Simon

Welcome to the ICOA forum, Mr.Bond, James Bond!

Dave summed it up very nicely! Some years ago, I wrote a piece titled "The CBX throughout the years" . It was intended to point out, not all, but the major differences in the 4 model year issues. It was published as a title page article over on CBXWorld and may still be there, buried way back.
I have the write-up , but as Dave indicated it would be a rather lengthy piece and too much for a post. I could send you an e-mail attachment.

I was a little surprised by the quote above, because you said before, you are done with riding fast on the street. Mind you, although the 80 CBX has some 5 hp less than the 79, it is no slouch compared to its older relative. A well tuned 80 is as fast as a just decent running 79. On eother advantage is the price. As most people think the 79 is the one to have, 80s are usually a little less expensive. Although as far as I am concerned it should be the other way around. 1980 CBX models, both the Japanese and the U.S. versions are significantly rarer than the 79 and may increase in value as collector models more than the 79 in the future.
Stay connected and keep asking questions. There is all kind of experience here.

[1jamesbond]

Hi Dave & EMS,

Thanks for the thoughtful replies. Cams and carbs is kind of what I remember as the difference. I realize there seems to be a conflict in my thought process when I say I don't want to ride fast (relative to how I used to ride) and asking about boosting the performance of a1980 to 79 specs. I remember back in the day everybody was struggling to meet emission standards with carbureted engines and leaning them out, often in the midrange which made for some weird flat spots in power delivery. I'm guessing that the intake cam timing was advanced for 1980, with a corresponding loss of duration? Were the carbs physically a smaller bore or is it just tuning differences, needles, jets and the like? I'm guessing the ignition advance curve was also changed a little, but that's probably pretty easy to modify...

If I pull the trigger on this impulse, my ideal would be to tune the bike (which ever model year I end up with)using period correct parts to make it perform and run as nicely as possible without making any obvious modifications from stock, except for maybe some minor bolt ons, like brakes and suspension ( no modern upside down forks or anything like that)

BTW surfing the forums, I've got to say I've seen some really nice naked 81's and 82's although my gut tells me I'm better off with a 79 or 80 if that's what I want to end up with..
Thanks again.