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

Single to Dual Amal Setup

Discussion in 'Norton Commando Motorcycles (Classic)' started by Tornado, May 22, 2019.

  1. baz

    baz VIP MEMBER

    Joined:
    May 26, 2010
    A mate of mine has an older t100 Bonneville it's a carburettor model
    He can't get past me when we go out
    I don't know if this is typical of that type of hinkley Bonneville but I took one for a spin a few years ago and all I can say is it was completely underwhelming!
    Anyway tornado are you going to stick with the twin carbs?
     
  2. Tornado

    Tornado VIP MEMBER

    Joined:
    Dec 5, 2017
    My bonne is EFI and I 've done a standard set of mods to waken it up some. Removed O2 sensors and secondary air injection. Opened up air intake housing and silencers, remapped fueling with professionally made map from TTP tuning. So it goes very well and sounds much better than stock.

    Too early to tell if dual carbs will stay. Got to see how finicky they are.

    Any thoughts on the left right exhaust sound differences? Right is chirp-chirp-chirping while left is pop-pop-popping at idle. More dialing in , normal or something to worry about?
     
  3. worntorn

    worntorn

    Joined:
    Dec 22, 2006
    Are these still the same small hole silencers that were on the bike before?
    If so, there is more power to be had there.

    Glen
     
    Last edited: Jun 2, 2019
    baz likes this.
  4. baz

    baz VIP MEMBER

    Joined:
    May 26, 2010
    Probably a bit more tuning needed,
    Not sure what ignition you have but if you can't sort it with the carb tuning try swapping spark plugs/plug leads/ coils just to eliminate an ignition problem or you can end up chasing your tail
    Are the silencers identical?
    I take it that it didn't do this with the single carb?
     
  5. Tornado

    Tornado VIP MEMBER

    Joined:
    Dec 5, 2017
    Silencers are the stock MKII 850 peashooters, with welded in mutes. I've swapped out the balanced headers for non-balanced (though planned for future a cracked weld on the left balanced header forced this earlier than planned). Ran the non-balanced pipes with the single for a couple of weeks and did not notice this chirping from right side.
    Now with duals, chirping is quite audible, almost comical, out right side. Running Wassel EI with 2, 6-volt Lucas coils and Champion plugs...same as I've had for a year now. Will conside swapping some bits around to see what happens.
     
  6. Tornado

    Tornado VIP MEMBER

    Joined:
    Dec 5, 2017
    Got a stepped drill bit on order to bore out the mutes....
     
    worntorn likes this.
  7. Tornado

    Tornado VIP MEMBER

    Joined:
    Dec 5, 2017
    FYI...I just tried out a new-to-me compression tester (snagged from an old timer on local craigslist)....I'm seeing nearly 150 psi each side if I hold throttle wide open while kicking ('bout 125-130 if throttle left at rest).
    That seems pretty decent, no? She's got about 13,000 miles now is clock doesn't lie.

    EDIT: Now reading some threads stating this testing should be done on warm engine...so will need to repeat.
     
    Last edited: Jun 2, 2019
  8. acotrel

    acotrel

    Joined:
    Jun 30, 2012
    Here are usually two trade-offs with getting more power - fuel consumption and noise levels. A fast but silent bike is a pretty rare thing.
     
  9. Jagbruno

    Jagbruno

    Joined:
    Jan 6, 2014
    Mine is very loud.
     
  10. Tornado

    Tornado VIP MEMBER

    Joined:
    Dec 5, 2017
    Just an update. I was have some misfiring issues on my first longer run on dual carbs. Reviewed a bunch of threads and checked a variety of items. One thread mentions to give a wiggle to carb bodies while feeling for movement at the mounting surfaces. Well found a very small amount on one carb to mani flange. Decided to pull them off bike to get them snugged and rechecked pilots and fit new Wassell anodized slides while there. Performing Bushmans setup and she seems to running better on a test run. The left side chirping Seems better and somewhat possible to dial down with air screw and stop screw adjustments.
     
  11. Tornado

    Tornado VIP MEMBER

    Joined:
    Dec 5, 2017
    Did an all day ride yesterday. Made 45 mpg over a 70 mile run North and 40 mpg coming back. Diff may have been elevation and or head winds. Bike seemed to run better first half of day and seemed to develop a missfire latter half. Back home checking plugs show sooty right, chalky left. This was not so on shorter runs around town and up and down a mountain.

    Showing oil seep from two front head studs. Will try removing and applying sealant.

    Exhaust roses eased off by end of day. Need to watch them better.

    Speedo drive pretty much shot as needle is ±10 mph. However if I goose up to 60-70 ish needle stabilizes and hold until speed drops to less than around 50 ish.
     

Share This Page