1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Zen and The Art of Norton Maintenance RTW Tour - 850 barrels needed

Discussion in 'Norton Commando Motorcycles (Classic)' started by johnfitzw, Jun 17, 2018.

  1. johnfitzw

    johnfitzw VIP MEMBER

    Joined:
    Jun 19, 2014
    850 barrels in good condition needed (East Coast USA) .

    Ladies and Gentlemen...

    Does anyone in the US (prefer close to Boston) know of, or have a good used set of 850 barrels, +0.020" / 77.50mm or less that I can purchase?

    (UPDATE 18 JUNE: I managed to find what looks like a good set of +0.020" barrels on Ebay last night/Sunday 17 June. I'll know more once I've received them on Wed - thanks to all for suggestions and help)

    I've just airfreighted my 74 Commando 850 Interstate to the US from New Zealand, planning to spend 3 to 6 months meandering about riding in the US and Canada, on a personal Zen And The Art of Norton Maintenance Tour, visiting the many North American friends I've made through my tour guiding business in NZ over the past 23 years. After the US (next Northern Hemisphere summer) I plan to ship the bike to Japan to ride there for a while , then later on to the Asian mainland, and then overland to the UK heading westwards.

    Amongst other preparations and modifications, I decided to have the cylinder bores Nikasil treated for durability back in NZ. The bike has been running strong and well here in the US , but yesterday the bike suffered a seizure on the drive side piston, in what looks to be a case of failure of the Nikasil plating - a big track of the plating has stripped away near the pistons gudgeon. I was only cruising at 60mph/3500pm at the time.
    The right/timing side piston and bore are perfect - only the drive side is damaged. The bore size is 77.50mm, or +0.020" oversize.

    I know where to find the replacement +0.020" forged piston I need (the bike has a big valve Full Auto head) however I find myself in need of a good condition barrels, either standard, or with a good condition 77.50mm / 0.020" bore.

    I'm in Boston at present, so would prefer a local solution, but would be happy to have them freighted from anywhere in the US or Canada..

    Please PM, or call my US contact number (650) 741-4160

    Thanks in advance for any assistance or suggestions..

    I would like to take this opportunity to thank John & Sue Healy and their son Tom of Coventry Spares in Middlesboro, MA, for their kind assistance and generosity in helping me out with a few earlier problems. They had everything I needed on the shelf - great people.


    John Fitzwater
     
    Last edited: Jun 18, 2018
  2. davamb

    davamb

    Joined:
    Nov 11, 2008
    Hi John,

    much envy on your trip, the same has been on my bucket list for some time.
    I had a similar failure on a Honda waaaay back, the guy who built my engine failed to put in a c-clip that held the gudgeon in place. Eventually it slipped to the side and milled a prefect groove up the side of the cylinder before seizing completely. Can't recall off the top of my scone how the pins are retained in a Commando, but you sure the same hasn't happened there?
     
  3. CanukNortonNut

    CanukNortonNut

    Joined:
    Aug 8, 2005
    Hi John,
    Too bad about your seizure.
    Did you check here in the for sale section: Broken lnk removed

    I am not sure where he is located but it still needs to be bored to +0.020"
    Option #2: You might want to contact Dynodave here. He is located in around the east coast area.
    Cheers,
    Thomas
     
    Last edited by a moderator: Sep 17, 2018
  4. RoadScholar

    RoadScholar VIP MEMBER

    Joined:
    Dec 28, 2008
    The barrel listed in the for sale is in Australia, DynoDave is located on the North Shore of MA

    Why not, simply, punch the barrel you have out to +.040 (+.060 if needs be) and be done with it? My shop is about 35 miles west of Boston and I'd be happy to assist, I have a local service that bores my cylinders and can hold any skirt clearance you specify. John, Tom and Sue (Coventry Spares) are also in my "back yard" so getting +.040 pistons assemblies (or +.060) is an overnight order for me, or you. You can reach me at 978-212-5432.

    Regards,

    Bill.
     
  5. CanukNortonNut

    CanukNortonNut

    Joined:
    Aug 8, 2005
    Bill,
    Great Just around the corner. I don't know too many Norton specific shops in that area. I see two 06-5074 barrel sets in stock at Old Brits http://www.oldbritts.com/11_065074.html but that will cost a lot more than a re bore and new pistons. It will still cost an additional set of standard pistons to get him back on the road, if John goes that route.
    Hope it all comes together.
    Cheers,
    Thomas
     
  6. Brooking 850

    Brooking 850 VIP MEMBER

    Joined:
    Oct 3, 2011
    John , does this bike have the 2EX1 system on it?
    Regards Mike
     
  7. johnfitzw

    johnfitzw VIP MEMBER

    Joined:
    Jun 19, 2014
    Hi Dave - I have the engine apart now - it wasn't the circlips. Still getting the the bottom of what caused the seizure, but I have a couple of leads to check out.
     
  8. johnfitzw

    johnfitzw VIP MEMBER

    Joined:
    Jun 19, 2014
    Hi Mike - indeed it does. Before we left NZ we added a stainless reversion cone on the end of the muffler - it's toned the volume down a tad, and fattened the mid-range... though with the 5 speed TTi box, it's hard to compare apples with apples. My previous ride in NZ with your pipe was with a stock 4 speed with v long gearing, and I often found I was between ratios - as hoped, the 5 speed has completely fixed that issue.
     

    Attached Files:

  9. johnfitzw

    johnfitzw VIP MEMBER

    Joined:
    Jun 19, 2014
    Many thanks for the link and suggestions Thomas - I hope the barrels I purchase on ebay y'day are the solution.
     
    Last edited by a moderator: Sep 17, 2018
  10. johnfitzw

    johnfitzw VIP MEMBER

    Joined:
    Jun 19, 2014
    Many thanks for the great suggestions and kind offer Bill - if i get stuck I'll take you up on the offer.. :)
    I don't believe it's a straightforward job to re-bore a formerly nikasil plated bore. I'm not totally confident of the accuracy of this belief, but I believe the nikasil material needs to be removed by acid etching from the old bore, before a the new bore can be machined. That etching process can take up to a week, apparently - it's a slow process.
     
  11. Brooking 850

    Brooking 850 VIP MEMBER

    Joined:
    Oct 3, 2011
    Thanks John, looks good, quite the pack horse.
    Is that a pre Mk 3 motor in a Mk 3 frame or just a Mk 3 backend?
    After you mounted the 2EX1 system, did you need to change jetting and also , did you need to rejet after the change of the reversion cone?
    Good luck with the repair.

    Regards Mike
     
  12. johnfitzw

    johnfitzw VIP MEMBER

    Joined:
    Jun 19, 2014
    It is indeed, quite the packhorse Mike - I guess I have about 40kg in total in luggage at the rear, maybe 7kg in the tank bag. So 47kg / 103.6lb in total - the ideal weight of a good pillion passenger :D
    It feels absolutely great, planted and taut on the road, like it's never felt before. Even in Packhorse Mode, there's not even the hint a wiggle on rain grooves or seal edges.
    I made a number of upgrades to suspension and frame before departing NZ:
    • I changed the offset of both front and rear rims to put the rim/tyre centres on the frame centre line (that's hard to do on the front due to the front hub offset design) - the rear had been 12mm to the left, and the front 9mm to the left. The bike now tracks dead straight if I let go of the bars.
    • Madass's Landsdowne fork internals
    • Jim Schmidt's Turcite fork bushings
    • New Andover Norton fork tubes with polished inner bores. My old fork legs looked like the internal bore had been drilled out with a wood auger, causing a lot of stiction on the fork springs - I'd like to try a hi tech antifriction coating on both fork springs and the internal fork tube bore.
    • Ohlins rear $$$$hox supplied and fettled by Robert Taylor of KSS in New Plymouth, NZ
    • Jim Comstock's cyl head steady
    • New "soft" isolastic rubbers from RGM
    • And the best modification of all - a Herb Becker style engine/gearbox cradle lateral support block - many many thanks to Doug Macrae for revealing his/Herb's secrets here: https://www.accessnorton.com/Norton...o-handling-secrets-revealed.8641/#post-113806
      This last mod has transformed the handling - the bike feels taut and planted even on poor, grooved, tracked surfaces, fully loaded.
      Every Commando should have this mod.
    • Additional frame loop cross members as shown in Doug's posting above
    • A Jim Comstock style under engine buffer/support mount to support the front isolastic and prevent sagging.
    Re the zorst:

    No, I haven't changed the jetting... but that may have contributed to the recent seizure.
    Adding the reversion cone took away a mid range flat spot that I was experiencing with the 2:1 that I had on initial fitting - the bike didn't want to pull hard from 3000 to 3600 in top, as it had previously ( 4 speed, long gearing, 4S cam, FA Big Valve head ) The bike just would accelerate slowly and give the trademark Woooooooh intake roar, until 3750 and then it would suddenly turn into a two stroke screamer. With no jetting changes the cone filled in this flat spot... However... I have hunch that my choke pistons on my 36mm Mk 2 Concentrics may have been leaking for some time. I replaced the brass choke pistons on the morning of the seizure. I think the leaking chokes may have been contributing fuel and covering up a lean needle setting. I'll be richening things up a tad once the replacement barrels arrive..

    Re the frame:

    The bike was originally a Mk2A 850 Roadster that I bought complete in pieces in Perth, WA in 1977, when I was working as a geologist there.
    My friend ( Brian "Budgie" Morgan of Morgan Motorcycles) had a Norton spares shop, and had a lot of Mk 3 850 second hand spares. I wanted the stronger swing arm, improved swing arm mount, and the improved disc rear of the Mk 3 models, so I bought all of those components from Budgie. I also fitted Mk3 style isolatistics, a Mk 3 head steady and the spring head support at the same time. I had to slot the top gearbox mounting on the Mk3 cradle so the primary chain could be adjusted of course, plus I had to come up with a way of adding a hydraulic footbrake m/c on the pre-Mk3 footbrake lever.

    The improvement in handling was noticeable immediately, mainly from the stiffer swing arm. The factory pre-Mk3 swing arms seem to have the stiffness of limp celery.

    The bike has been set up that way since 1979 and has been maintenance free.
     
    Last edited: Jun 19, 2018
  13. Brooking 850

    Brooking 850 VIP MEMBER

    Joined:
    Oct 3, 2011
    Thanks John, hope your repair goes well.
    I noticed that once I had fitted my 2EX1 to my race bike I had to go up a main jet size or 2
    very informative.
    Regards Mike
     
  14. johnfitzw

    johnfitzw VIP MEMBER

    Joined:
    Jun 19, 2014
    Thanks for the tip Mike. With the wonderful service and support of Coventry Spares in Middleboro, Mass, I arranged to receive bigger main jets out to 330 (currently on 300's) 107 needle jets (just in case), and the richer 2A1 needles today. Plus, I purchased that Air Fuel/Lambda gauge and sensor today - I'll put the fitting into the collector, and will monitor the A-F ratio for the next few weeks as I ride.
    Hope you're not to cold down there... :)
     
  15. CanukNortonNut

    CanukNortonNut

    Joined:
    Aug 8, 2005
    John,
    Please keep us in the loop on how the re-bore repair goes. We like road trips. ;) Keep on keep-in on...the adventure continues. :cool:
    Cheers,
    Thomas
     
  16. worntorn

    worntorn

    Joined:
    Dec 22, 2006
    Hope you make it out west after the top end fix.
    There are thousands of miles of twisty roads thru beautiful scenery out here.
    Can provide maps.

    Glen
     
    Last edited: Jun 25, 2018
    rvich likes this.
  17. rvich

    rvich VIP MEMBER

    Joined:
    Jul 25, 2009
    Lewis and Clark could have used a couple of Commandos. That route is a favorite now but it just about killed them!
     

Share This Page