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Commando Top Speed? (2010)

Discussion in 'Norton Commando Motorcycles (Classic)' started by highdesert, Dec 21, 2010.

  1. texasSlick

    texasSlick VIP MEMBER

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    Jan 2, 2013
    Aw hell .... it ain't what you got, it's how you use it.

    Slick
     
  2. XTINCT

    XTINCT VIP MEMBER

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    Jan 10, 2012
    Is it possible that not everything is bigger in Texas? lol
     
  3. hobot

    hobot

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    Oct 19, 2005
    I was such a newbie in early 2000's I had no idea how upset the squids and some elites, would get, similar to Brit Iron owners/racers would later over Ms Peel performance. Ms Peel was ~ 15 mph faster top than my SV650, 70hp/365 lb which ran out of pull approaching 120 then needed down hill and many more seconds to reach 127ish on its modern electronic speedo. Torque gives the pull power to speed while hp determines how long-fast that pull lasts. Some the highest times in my life so broken heart never got chance to put on the Drouin with GPS video. So any suggestions on 18" & 19" tires that can sustain over 150 mph or not come apart around 175 topping out? Just guessing here from past experience and calculators.

    Peel performed exactly as you'all have described various road race Nortons, too sluggish to try for 120 in short Ozark opens - until so frustrated before selling d/t better performing moderns - I removed 10 plate supertrap for 12 ga slug through megaphone end cap to change my mind on best tool to spank/surprise my self and others - just not on any forums of course. Peel was my first engine build attempt, so extra points against believing any claims of a beginner in open shed shop.
     
  4. Mr. Rick

    Mr. Rick VIP MEMBER

    Joined:
    Feb 6, 2009
    "So any suggestions on 18" & 19" tires that can sustain over 150 mph or not come apart around 175 topping out? "
    No, but cd get close w Conti Classic Attack, V-rated (149)
     
  5. Triton Thrasher

    Triton Thrasher

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    Feb 10, 2009
    Haven't you heard of the Panhandle?
     
  6. JimC

    JimC

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    Oct 12, 2007
    What is the color of the sky in your world? Special meth, perhaps?
     
    Last edited: Apr 13, 2018
  7. oldmikew

    oldmikew

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    Jul 25, 2015
    Its not how you hit the airstream, but how the airstream leaves the bike that counts ..
     
  8. hobot

    hobot

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    Oct 19, 2005
    1 up/3dn, a funny thing happened on one of Ms Peels hunting spree's, after couple seasons in her prime, finally encountered the only brand/model I'd not tested against - Duccati 998 Monster squadron, about dozen of them. I happened to turn onto my curvy commute Hwy just ahead of them, so ran up to the ton to see if could pull out their hot shot, sure enough one left the pack, so race was on! I kept 100's yd lead up to ~120 in short opens but mostly 70-90s d/t tight-tish 35mph blind turns, til hitting mile long straight, pulled up behind a car 55 mph to wait for Duc to catch up and see what I was on, thinking they'd nod, wait for me to get around car, nope, instant helmet jerk up then about wheelied off, so I down shifted to what i thought was 2nd but only hit 3rd so on nailing it i heard metal cracking sounds but Peel pulled stronger than the Duc to catch it one bike length behind in ~1/10 m before next turn then hung a few lengths back watching them knee dragging turns like on one else encountered, til we stopped a few miles/min. later in Kingston wide spot in hwy. Duc pilot popped off helmet to see a cute gal hair tumble down, frowning at me! I had to pee bad so walked into clinic then back out to see whole squadron surrounding Peel and seeing vac/boost gauge were arguing on where I'd hidden the supercharger as inconcievable to them such antique could go so good. When i said ani't installed yet the ones kneeling fell backwards while the ones standing jerk backwards in shock too.

    I had let air down 1/2 to get across mud flats prior, so aired up to get handling back and lit out on next even more twisty tight section, Peel able to lead to 90's but got out hp'd passed in 1st straight to follow along till tranny stuck in 4th, so pulled over, waited for rest of squadron to tell em what happend and thank gal for hell of road dance. 3rd gear set lost 1/3 their teeth. When Duc's came out with 1198cc - that was what made me decide to build a boosted big block.
     
  9. 1up3down

    1up3down

    Joined:
    Jan 12, 2011
    so broken heart never got chance to put on the Drouin
    --------------------------

    ok Hobot now I am really confused, you said that your Commando hit 135mph, I assumed you had the Drouin hooked up but now you say that you never had a chance to put it on

    So my question is - given your Commando was a Combat, correct? and it was not running a blower, correct?
    then how could it possibly have reached an incredible 135mph? Seriously I would like to know
    I have owned six Commandos including a very modified Combat with two into one into two Dr Blair exhaust, lightened rockers
    and with a 22 tooth front sprocket at sea level with me weighing all of 120 pounds I managed to be verified flat out at 117
    SO please explain your 135mph? thank you
     
  10. hobot

    hobot

    Joined:
    Oct 19, 2005
    Did not do it much as scary in public but would sometime crest in straights about 130 to catch a few more down hill. Both my SV, and Chevy hot rod van, Olds Vista Curser, Mercedes 6.9L and P!! dragster all hit aero dynamic transition indicating ~120 mph and so did Peel. That's my threshold of joy ride thrill into hunker down survival mode. At Peel top end range areo dynamics dominate, knee out or elbow or helmet out of line felt as drag or pilot buffet. I want to recreate engine to test as pretty simple/cheap mostly factory. I think the 4 main things were, smaller lighter flywheel, small port head and 2-1-long hollow mega exhaust, and, bigger single carb with trip up lip manifold. I'd gotten dam handy on SV dragging ass on 1st Combat rebuild discovering major stuff bent shot. Took Codes corner class on Ninja, to over 145 for comparison sense, to wish I'd not tripped up on Combat POS. Accidental combo of world wide advisors/vendors before accessnorton, splashed together to become my tool of choice, with earned name, in funnest dangerous technical pavement games.
     
    Last edited: Apr 13, 2018
  11. hobot

    hobot

    Joined:
    Oct 19, 2005
    hobot tall tales asside, Mz Peel current 920 engine is similar to best there is build by experts + spiffed up Drouin + power adding fluids, and Canaga has a spare streamliner laying around with unneeded Nitrious blaster ... would it reach 200 or melt first?
     
  12. WZ507

    WZ507 VIP MEMBER

    Joined:
    Dec 26, 2013
    With a 200 lb rider and 33 psi inflation pressure the K81 4:10 x 19 on my 850 has a radius of 12-13/16" (diameter 25-5/8") when stationary.
     
  13. pommie john

    pommie john

    Joined:
    Nov 18, 2005


    When I was racing my Atlas/Commando hybrid, according to my calculations, with a 21/42 primary ratio and a 21/42 rear ratio it should have been doing 132MPH at 7000rpm. I took it to the dyno several times and each time the road speed of the dyno matched my calculated road speed. Since I saw 7000rpm on the track I assume it must have been doing about 132MPH. The dyno showed 58 horsepower at the rear wheel.
     
  14. oldmikew

    oldmikew

    Joined:
    Jul 25, 2015
    That sounds right and presmably with a fairing.. Little attention has been paid to fairing shape and design in this thread. The Avon fitted to mine puts 10-12mph on top speed, but the bike is overgeared so in real terms it could possibly put more on top end. It derives from the fairing used by Veloce on the 24hour attempt . There was apparently a factory tester who could always get10mph more than anyone else out of a bike. And he was seriously obese. The implication being his bulk gave a better areodynamic shape . Its how air leaves that is important.
     
  15. 1up3down

    1up3down

    Joined:
    Jan 12, 2011
    hobot tall tales asside
    -----------------------------

    You said your hit 135mph on a non blower Commando and now you say it was a tall tale. Why lie, what is the point in lying?
     
  16. hobot

    hobot

    Joined:
    Oct 19, 2005
    Ugh, annoying as a hound sniffing at your finger pointing out a squirrel to chase. i gave my road facts and what was done to engine mainly in hopes someone else might see what they may be missing out. I risk being called a liar every time Ms Peel facts reported. Got so annoying at gatherings with the hot shot hot rods snickering/rolling eyes at my obsolete has been, I perked up on their smug gun fighter attitude, so'd meekly agree, yeah, so can I tag along -till bored, to put some spirit in their efforts, then zip my way to head of heated pack, to pull out the one worth playing with, then after a decent turn, rest was solo as Peel was fast enough with a big lead in the opens they couldn't catch up. I was more impressed with Peel's acceleration to 100 than useless top end. My beginner/girls' SV650, carbs modiefied, did not have the UmphF to even stay with these packs in any opens, especially climbing ones, so even if I could out handle them, simply too out gunned. Still leaves me tingling on what I almost missed out on if only preforming as others expected. Did it with only 2 after market non factory engine parts too, flywheel and single carb, which of course is unbelievable too.
     
  17. WZ507

    WZ507 VIP MEMBER

    Joined:
    Dec 26, 2013
    I too concur as your calcs are spot on. An interesting aside to your gearing is that you ended up with an overall gear ratio of 4.00 (42/21 * 42/21 = 4.00) which is identical to a stock bike running a 23T countershaft (stock primary * final drive [57/26 * 42/23 = 4.00]). So give or take a mph or two, due to differences in tire rolling radius, you're spot on.

    A previously posted plot of this information is found at the link below.

    https://www.accessnorton.com/NortonCommando/sprocket-size-question.21680/#post-323749
     
  18. hobot

    hobot

    Joined:
    Oct 19, 2005
    Late Ms Peel had 2:1 Dreer belt, 21T sprocket plus taller dual purpose 120 tire on 'narrow' 18" WM3 rear, which puts her in the stock 22T range. Tires, if run over rated limits definitely expand, 3 to 10% of width, depending on tire size/construction, as chopper dudes found out having to usually leave at least 1/2" clearance on rigid frames they enjoyed at turnpike+ speeds. Bolts shaving off 1/32" or so if acceptable to chopper offensives. Commandos are so naturally torqey upping the sprocket mainly allows staying in a gear longer better pulling rates to faster speed, than if had to shift sooner on smaller sprocket. Some vintage public dragsters said they did best just dropping clutch WOT in 4th and hanging on. No dual purpose I could find was rated for 120+ mph.
     
  19. 84ok

    84ok

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    Aug 10, 2014
    speedo can easily be off ~ 5-10 mph at speed
     
  20. 1up3down

    1up3down

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    Jan 12, 2011
    ok Hobot, just to end this being perfectly clear

    you are saying that you hit 135 mph on your 750 Commando with no serious engine modifications and in fact with only single Mikuni
    the laws of physics and mechanics have never been broken, no "miracles" have ever happened
    what exactly do you get out of lying?
    or is this another one of those "alternative facts" things?
     
    JimC likes this.