72' 750 vs 75' 850. Normal?

what was the octane of gasoline in the early 70's? Was it higher?

Hey Mr Fastback...Did you say Redwood Road? As in between Castro Valley and Skyline Blvd in Oakland? I used to ride that route frequently...10 or more miles of twisties.

Fastback,

A 305 Superhawk is what I had before buying the '72 Commando. It explains why I wasn't concerned about hitting 8000rpms on the Norton - that wasn't really pushing the Superhawk. Never looked back to Japanese road machines after that first Norton. Only rode Nortons, BMWs, Ducati, Triumph, BSA, Rickman since 1973.

Yes, the gas was higher octane and leaded in '73 and the engines could rev free. Have run race gas from time to time in the combat...works very nice. Lately, just retarding the heck on the Lucas RITA to get rid of the pinging.

MrFastback said:

Do any of you also ride old Bonnevilles or BSA's?

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I can only compare the combat engined Commando 750 with my current Triumph 650 Trophy, a BSA Rocket Gold Star that I owned until just a couple of years ago, and a Manx racer which I still own. The Commando definitely feels fast. I know the Trophy is a single carb bike, but the Commando just eclipses it. It's worth noting that I've ridden the Trophy with others on Bonnevilles and it actually hangs in there with them until you get to the higher rev range.

The Commando feels much faster than the RGS and I actually think it will hold it's own with the Manx. The Manx has more low-end torque, but the Commando has the edge in top end. What the Manx has over the Commando is the frame of course. The Manx just has rock solid handling on the track.

Bottom line is that I think the combat engined Commando is the fastest stock, classic, street legal Brit bike that I've ever ridden. It sounds and feels (in terms of acceleration) like a factory racing machine of the era. The handling is a different story.

Interesting debate, and the extra fuel tanks some of us now carry for our love machine may be a cause! The best route would be to compare the 850 to another 850, and you would have your answer(perhaps) before you do anything radical like shave your extremities and eat less pies!
I watched a video of a Commando going round Donington (clip was on the forum here-donington) and was impressed by the way the guys motor was spinning up the rev range compared to mine. But mine has a slipping clutch and the speedo has gone awol so i never know what is going on. Come the winter it will be sorted I hope.
I don't believe I have ever had the best out of the beast yet, and if I compare it to my laverda montjuic 500 from 20 years ago when i was 14 stone on my 850(now 18st- all muscle....) the Monty was much more exciting. it could be i am more mechanically sympathetic now!
If I wasn't so tall there would be an Aprillia RS250 in the shed as well.

No one I knew ever had a Triumph or BSA triple. I think they may have cost just enough to price it away from kids. How do they compare to a Combat Commando for power? I have read that they were very quick.
As to your Manx what a lovely machine they are. All I can compare the handling to might be my current featherbed, and I imagine the Manx is better still.

I have a 72 combat. It will indeed smoke an 850.
Here's my 2 cents.
You have a 70 Boss mustang, I have a 73 mustang.
You will run circles around me.
By 1974 the motor vehicle industry was neutered by most governments.
I'm really supprised at the resurgence since the 1990's w/ muscle cars
and sport bikes.
There was no reason to put those silencers on the MkIII?
Why,? to please the great socialist state of Kalifornia. 1st in nation to require useless smog devices.
All C'dos came into the US for sales in Calif. and @ Berlinners in New Jersey.
That is where my bike was delivered than sold by a lawn mower shop.
Go Figure.
It runs 4100 RPMS at 70 mph all day.
I'm fatter,balder,and slower reflexes but it still is scary fast.
Your intuition is spot on!
Marshal

There was no reason to put those silencers on the MkIII?
Why,? to please the great socialist state of Kalifornia. 1st in nation to require useless smog devices.
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Geez Marshall, hope this is jabbing fun at California. The black cap silencers were originally to meet European noise requirements in '73 on the 850 MkI. They didn't hit US shores until the next year and even then most '74 850s sold in California were MkIIs with peashooters and ham can air filters.

I can tell you the smog requirements in California were not useless. Living in the Bay Area since 1969, the air quality is very much better now than in 1970 even with double the population. You can actually see across the valley in summer.

Just as a point of interest, it takes about 1 hp for every 6 extra lbs of weight you add to go the same elapsed time. I saw this fact years ago in a muscle car book where they discussed how the period cars started out lean and each year put on weight. Kind of like people. Detroit kept upping the hp but the cars went no quicker. Zora Duntov fought the installation of the big block in his Corvette as he thought it was a lump. He was not satisfied until they managed to cut some weight from the car. I have managed to have 4-5 Commandos but all with 750 power so I cannot compare the two. I think if you check the magazines of that time you will see the 750 was a bit quicker. You can also note that some motors run like the wind and others are dogs for no apparent reason. Shelby used to dyno the Cobra engines and keep the better ones for his team and give the lesser o/p ones to the Brits. I can compare the 750 Norton to the 750 Triumph. The Norton pulls harder as it is geared lower. I have had my Triumph for only a few years and am having a hard time warming up to it. The Norton reeks of quality and rides much more smoothly and is more stable. The Triumph engine rattles a lot more but seems to get it done in spite of this.I am quite comfortable on long distances wih my Norton and have ridden one across the United States. I would not do so on the Triumph. Then again I set out to initially get a Bonneville way back in 1970. Both my bikes are pretty trouble free as I get them working well then just ride. Most gearheads are never satisfied with what they have and want to add this and that and modify this and that. This generally leads to troubles. As my dad used to say, the thing has WRENCHITUS.http://s217.photobucket.com/albums/cc64 ... ter=images

When you were out on the Bay sailing there used to be brown cloud over the city. I'm a newcomer, only been here around 30 years or so.
I'd love to have fuel injection on my Norton but installing it wouldn't be very practical.

Cookie said:

No one I knew ever had a Triumph or BSA triple. I think they may have cost just enough to price it away from kids. How do they compare to a Combat Commando for power? I have read that they were very quick.
As to your Manx what a lovely machine they are. All I can compare the handling to might be my current featherbed, and I imagine the Manx is better still.

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Cookie,

Back in the early '80s I had a bog-standard T150V, and a friend had a 750 Roadster - I don't remember it being modded in any way, or what engine it had, but the peashooters were definitely louder, so I'd guess they were straight through.

We used to swap about from time to time, and I always remember the T150 being more demanding to ride, like it really needed all its gears, whereas the Norton didn't seem to care. The T150 was also a bit of a porker by comparison.

We also had T140 Bonnevilles (I still have one), and the Commando was just so much stronger than any of the Triumphs.
I couldn't say if it was out-and-out faster, as we didn't really go for maxing them out (and I was 50 lb haevier than my mate!).

We used to go to quite a few rallies, and I was always jealous of how much better the Norton ate up the miles; definitely more long-legged than the Trident . I can't remember the Commando being faster, but it was certainly more relaxing at high speed.

The only bike which did it better was Italian, but a somewhat younger design

Thanks Andy,

If one of those triples ever came my way at a deal I'd be very tempted.

I had a new 1969 Trident. Pretty sweet bike. I didn't much care for the "bread box" tank. Now a X75 Hurricane is something I'd really go for.

Was the Hurricane the one that an American designed the body on? Craig Vetter?

One and the same Cookie.
Vetter of the great Vetter fairings of the 70's!

Cookie said:

Thanks Andy,

If one of those triples ever came my way at a deal I'd be very tempted.

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http://cgi.ebay.com/ebaymotors/ws/eBayI ... MyEbayBeta