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143MPH 850 MK1 Commando?

Discussion in 'Norton Motorcycles (Modern)' started by Bazz, Jan 11, 2012.

  1. wakeup

    wakeup

    Joined:
    May 1, 2013
    I once had the misfortune to fall off at well over 100mph....the speedo stuck at 105. My only memories are of sliding down the road behind the bike and being grateful for that, and how long it takes to stop.
    The bike was pretty badly damaged but still straight and repairable, but I was one big bruise. I must have landed on my left hand, because I have recurring aches and pains there.
    Given the choice not to be repeated!
    cheers
    wakeup
     
  2. hobot

    hobot

    Joined:
    Oct 19, 2005
    Yikes wakeup, obviously you got back in the saddle too. Nerve injury higher up can induce pain at sites w/o damage or greatly magnify othewise mild damage area. I remember the wheelie then bars snatched to lock then lightening from inside head then grey-blue-grey-blue-grey-blue-greenbrown- blue- greenbrown -blue in worse case tumbling no sliding. I'd already shaken up Codes school to spitting yelling show downs so big crowd gathered as Kieth Code inspected every inch of my rented suit expecting to bill me for it but could only find one 1/4" hole at L elbow and in dismay said no charge. Head-neck took the brunt fractured with brain swelling. I should of died then yet the 35 mph deer strike was way worse to survive. Its risky hobby. The Drouin Norton salt lake record holder was killed shortly after on a joy run when he hit rough salt off groomed track - gone.
    I have a handful of dead friends killed on cycles that whisper in my ear on the road and drifting to sleep, if I don't let myself really feel it - or involuntary noises reactions prevent it.

    [​IMG]
     
  3. Snorton74

    Snorton74

    Joined:
    Jul 28, 2012
    " because I have recurring aches and pains there."-wakeup

    A good accupunturist might be able to help you with that.
     
  4. hobot

    hobot

    Joined:
    Oct 19, 2005
    Acupuncture also amazes me how it pleases patients but I have little respect for it to re grow spinal postures and decay so you don't need no variety of acupuncture by pricking poking electrifying vibrating laser or injecting. I am a missionary for regrowing your own neck and spinal with cave man simple stretching and traction devices. Look up Chiropractic BioPhysics for their insights and methods. The other thing I found out with so many fractures at once was thinking I'd better up my mineral complexes to find how dramatic the pain relief could be. When I run out I can tell I'm an old injured dude but with enough of mineral complex + synergists and stretching I feel like going out doing it again and shrug off mangling joint injury as just annoyance for a few months. Bike damage repair takes way more money and time and effort to recover.

    [​IMG]
     
  5. SteveBorland

    SteveBorland

    Joined:
    Nov 15, 2010
    I've finally found my copy of the "how fast can it really go" article from Cycle, and I have done a pdf, but how to post it? Photobucket only accepts photos (!!) and I dont see any other posts mentioning this.
     
  6. Matt Spencer

    Matt Spencer

    Joined:
    Jul 25, 2010
    Quickly ! :p :D .
     
  7. SteveBorland

    SteveBorland

    Joined:
    Nov 15, 2010
    If all else fails I can do a photo of the article and post that I suppose. If anybody wants a pdf copy, ping me and I will email it.
    EDIT: the jpg files below are actually rather good though.

    /Steve.
     
  8. SteveBorland

    SteveBorland

    Joined:
    Nov 15, 2010
    Here we are...
    Worked better than I thought actually.

    [​IMG]

    [​IMG]
     
  9. mike996

    mike996

    Joined:
    Oct 29, 2006
    We used to use those nomos on the drag strip years ago and they were very useful. Mopar published them in their racing tech bulletins ( we raced Mopars in several SS classes) BUT, unless you actually know two of the three items, you can't come up with anything useful.

    IOW, for my Norton, unless I have done a dyno run (I haven't) , I don't know the HP and if I don't have a way (and the space) to get an accurate max speed - I don't ) the nomo can't help me determine anything.
     
  10. SteveBorland

    SteveBorland

    Joined:
    Nov 15, 2010
    True but on the other hand, if you want to get 145mph out of your trusty Model 18, by using an estimate for the drag coefficients you can get a realistic idea of how many horses you are short of.

    As an example, to return to the original subject of this thread, assming the the CDA figure quoted for an unfaired British bike up to 850cc (3.4-odd) is for a rider sitting upright, he would need around 90 bhp (and damn strong arms!). On the other hand, putting a fairing on it reduces CDA to 2-odd, requiring around 50 bhp.
    At least, I think its interesting... :D
    /Steve.
     
  11. mike996

    mike996

    Joined:
    Oct 29, 2006
    Totally agree re figuring how much HP you need to accomplish a task. I guess I was thinking more in terms of "proving" how fast my Norton (or anybody else's) can actually go.

    In looking at the nomo, it would indicate that a stock Commando should be able to achieve 120 ASSUMING the factory HP rating is correct. However, I have heard folks say anything from 45-50 ACTUAL RWHP is reality which would show around 110. Road tests of the time seem to come up with anywhere from 115 to 125 though how they came up with the speed is not always clear - radar gun, flying time through a trap, estimate...whatever.
     
  12. acotrel

    acotrel

    Joined:
    Jun 30, 2012
    I love the nomograph. What happens if you measure your BHP on the dyno, and calculate your expected top speed, then run with the front tyre at too low pressure so the rolling resistance is greater ? Or perhaps a mosquito farts and adds to the wind resistance ?
     
  13. acotrel

    acotrel

    Joined:
    Jun 30, 2012

    Perhaps the power / speed relationship is a squared one ?
     
  14. Rohan

    Rohan

    Joined:
    Aug 26, 2010
    Troll ??

    Perhaps someone has actually opened the engineering handbook...
     
  15. 1up3down

    1up3down

    Joined:
    Jan 12, 2011
    I have a book that has all of the Commando road tests from the magazine writers in both England and USA.

    In test after test, the "actual" as in tested, top speed is right around 110mph, with fastest tested being an 850 (21 tooth front sprocket) at 114mph

    the slowest top end tested, verified, was on a 1975 Mark 3 which topped out at 103mph

    in a number of the road tests, the top speed is often shown as "estimated" to be about 120, of course this assumes that the stock motor can actually pull to redline in fourth, which it, well, cannot at least from what I have read and my own wide open throttle runs on my Commandos being around 108-110mph, all stock
     
  16. Rohan

    Rohan

    Joined:
    Aug 26, 2010
    Unless they quote how many teeth are on the gearbox sprocket, and unless the teeth are more than the usual 19t sprocket, then the top speed will be around the 110 mph mark, max.

    If its only geared to do 110, then unless it was revved well beyond redline, thats about all it can do...

    Some of the proddy race bikes in that book of roadtests, with more teeth on the sprockets and a few extra ponies in the motor were tested out to 130 mph.
    That Dunstall hot-rod did 135 mph.
     
  17. hobot

    hobot

    Joined:
    Oct 19, 2005
    Takes over 70 rwhp for a Commando and pilot to do that.
     
  18. Madnorton

    Madnorton VIP MEMBER

    Joined:
    Jun 9, 2008
    Reported in an issue of Motor Cycle from the sixties was a 50cc machine recorded at 114mph - From what I can remember of the article it was a well modified German machine. So a well modified Commando should easily achieve 143mph in the right hands.

    Can't remember if I scanned the issue, I tend to forget as it is hard work trying to scan every interesting motorcycle article form nearly every copy of the Motor cycle and Motor Cycling magazine from 1950, the magazines are then sold on, so many thanks to those that have bought them around the world. Hopefully, in the future I will have database for all to share. It includes tests, the people, new bike introductions, show reports, technical reports, prototype information etc. I know some of you may be wondering how the hell did I get started doing this - it started as a joke at our NOC branch meet!
     
  19. Madnorton

    Madnorton VIP MEMBER

    Joined:
    Jun 9, 2008
    Though I do have the article of the Dunstall faired Dominator tested by Bob Currie at 135mph in the 60's.
     
  20. Rohan

    Rohan

    Joined:
    Aug 26, 2010
    Where did you pluck that number from the sky from ?
    It had a Dunstall fairing of course.

    And the Norton Villiers factory Mk1 850 that did the certified 143mph that this thread is based on didn't have those numbers either...
     

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