79 Cams in my 80


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zxbob
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79 Cams in my 80

Post by zxbob »

Im allways look'in to do something to my CBX - My recent mod is the installation of 79 cams allong with the
422 advancer . . . . I must say im pleased with the results. The bike has an improved mid range and upper
RPM pull.

The swap was really straight forward - it took FOREVER to re-shim the entire head. I checked the head /
cam caps with plasti-gauge and everything was good there. I just took it out for a spin and :mrgreen:

For you guys with the 80s who might want a few more ponies - its worth the effort !

Like a dummy, I did'nt check valve clearance prior to tear down so if you do that first you'll save your
self some time. The bike idles better, runs better . . . . Im going riding !

Bob
Last edited by zxbob on Sat May 14, 2011 4:27 pm, edited 1 time in total.
Good parts aint cheap ~ and cheap parts aint good !
oilheadron

Re: 79 Cams in my 80

Post by oilheadron »

I thought that all the 80 models had the 422 advancer retrofitted under warranty?? Or was it a 3rd advancer design that replaced the original '80 model advancer?

I'm so confused!!!
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zxbob
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Re: 79 Cams in my 80

Post by zxbob »

I think the 469A was the replacement (retro-fit) number :?:

Bob
Good parts aint cheap ~ and cheap parts aint good !
oilheadron

Re: 79 Cams in my 80

Post by oilheadron »

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Don
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Re: 79 Cams in my 80

Post by Don »

An interesting article

First because they claim that '80 model engine numbers between SC03E-2000001 to 2001773 were mounted in frame #s SC03-2000001 to 2001785 . . . . can't recall seeing that information before - Japanese made '80's seem to have frame and engine numbers pretty closely matched

Second - A 25 degree change in cylinder head temperature (from 275 to 300 degrees) costs you six and a half horsepower . . . . that's quite a change. Evidently, a cool CBX is a happy (and powerful) CBX

Don
daves79x
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Re: 79 Cams in my 80

Post by daves79x »

My observations about '79 vs '80 cams: I contend that if you didn't know which ones you had in the bike you were riding, you really couldn't tell the difference - unless you were at the drag strip or on the dyno. I love my '79 and will never part with it, but all the '80s I've restored, and others I've ridden, actually felt like they had MORE real-world power. They 'feel' smoother in power delivery and generally seem a little more 'torquey' for the normal riding we do.

Once the advancer issue was resolved, there was only actually two-tenths of a second difference, on average, in 1/4 mile times anyway between the '79 and '80 and you absolutely cannot tell that by the seat-of-your-pants.

Not to throw cold water on any of your efforts to extract the extra power, but this has been my experience.

Dave
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Re: 79 Cams in my 80

Post by EMS »

I agree with Dave. Any rework on an older bike such as installing different cams with a valve adjustment and a new iginiton advancer with an ignition adjustment will probably provide a significant improvement over the previous performance status.
I believe the adjustments that you made had more effect on the improvement than the actual components.
The seat-of-the-pants feel that we have on a bike is produced by the torque of the machine, not the horsepower. This being said, I don't think a well adjusted '80 will lack a lot behind a '79. Definitely not enough to "feel" it.
The infamous "In Search Of The 11 Second CBX" article and test by "Cycle" magazine of March 1980 , which elaborated on the different advancers showed the following : 1979 CBX with 422 advancer : 85.6 rw hp@ 9,000 rpm and 52.27 lbs ft @ 6,500 vs 1980 with 469A advancer : 82.8 rw hp from 9,000-9500 rpm and 51.09 lbs ft @ 8,000 rpm. At 5,000 rpm, a typical roll-on the throttle point , th 80 has an edge of 48.93 lbs ft over 48.40 lbs ft. All too small, however, to really make this significant. It could be the result of different ambient conditions.
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