Author Topic: Twingle, Twumper, Close Firing V, Big Bang  (Read 4888 times)

Rikugun

  • Visionary Grand Master
  • *****
  • Posts: 3250
Re: Twingle, Twumper, Close Firing V, Big Bang
« Reply #20 on: February 06, 2014, 10:32:41 AM »
hmm, I think I expected it to sound different. Or more different than it does? Is the "Starting the XZ400" clip in the stock firing configuration?  They are idling at different speeds in the two clips which doesn't help the comparison but I'll listen a few more times. Did changing firing pulses change idle sync?

How did you resolve the weak spark gremlin? Is this the same TCI as in the December '13 clip?
Never mid, just read the CHECKLIST  post...  So new question then - does this mean the other TCI's you tried may be good after all?
« Last Edit: February 06, 2014, 10:37:32 AM by Rikugun »
It is far better to grasp the universe as it really is then to persist in delusion, however satisfying or reassuring.  Carl Sagan

Prophet Of Doom

  • Contributing Member
  • Visionary Grand Master
  • ****
  • Posts: 2734
  • The really perverted one amongst us
Re: Twingle, Twumper, Close Firing V, Big Bang
« Reply #21 on: February 06, 2014, 02:13:12 PM »
Yes, that first clip was stock cam timing.   In my head it was going to sound like an SR500.  It doesn't.

I was having starting & overflow issues so the carbs were stripped (again) between times and the floats reset.  It's impossible to say what effect twingling has on sync and mixtures.  The twingled video is with mixtures at 3.0/3.0 turns and sync set by eye.  I'll shoot another shortly once I get it adjusted

Good thought on the TCI - I've fished it out of the waste bin

pinholenz

  • ROV Senior Member
  • ****
  • Posts: 645
  • Love the Light
Re: Twingle, Twumper, Close Firing V, Big Bang
« Reply #22 on: February 07, 2014, 02:44:59 AM »
Wahoo, that's brilliant! When you get a moment can you write the mod. up in idiot proof language so that others can have a go?

Good to hear the 400 is running. Does that mean you have to give the flying Citroen back? Or maybe trade it in for this crazy car built by another Kiwi that I discovered while listening to your Youtube clip. Slightly OT, but his next project isn't

http://www.youtube.com/watch?v=UexiOL8I_3Y
Only one '82.5  eXtreme Zen 550

Prophet Of Doom

  • Contributing Member
  • Visionary Grand Master
  • ****
  • Posts: 2734
  • The really perverted one amongst us
Re: Twingle, Twumper, Close Firing V, Big Bang
« Reply #23 on: February 07, 2014, 03:03:26 PM »
Not so brilliant, today it won't start.  However it's dipping below 10V on cranking so I've got the battery charging overnight.  I can't say I'm sold on this new Motobatt - It holds a charge well, and keeps cranking longer, but at a reduced voltage unless fairly freshly charged.

@ pinhole   All you are doing is holding both cams on 1 cylinder still while you rotate the crank 360 degrees (one full turn).  That's it.
Have another read of post #5 on this thread. Ask any Questions and I'll try and answer

I'm not giving the flying Citroen back, but I'll flog the 400 off on Trademe as soon as I can get it to start and go down the hill and back up a few days in a row.   That hotrod guy sounds like Sam Hunt



Rikugun

  • Visionary Grand Master
  • *****
  • Posts: 3250
Re: Twingle, Twumper, Close Firing V, Big Bang
« Reply #24 on: February 07, 2014, 03:42:00 PM »
@ pinhole   All you are doing is holding both cams on 1 cylinder still while you rotate the crank 360 degrees (one full turn).  That's it.
Have another read of post #5 on this thread. Ask any Questions and I'll try and answer
I realize this is a simplistic description to get the point across but... Make sure where you are holding the cams, the valves aren't open as there may be piston interference as you turn the engine over 1 revolution. Starting the process at TDC compression for the cylinder being altered might be a good idea.

If you don't want to jiggle the chain around the sprockets as you slowly advance the crank a revolution, start with either cylinder at TDC EXHAUST stroke. Loosen cam chain tension a bit on that cylinder and carefully remove the cams. There will be a bit of pressure on the valve springs so loosen the cam cap bolts incrementally. If you had thought to measure valve lash prior, now would be a good time to exchange shims.  ;)

Leave the crank where it is and reinstall the cams except now oriented for COMPRESSION stroke per the manual instructions, cam and sprocket reference marks etc. The cams will install easier as all the valves are closed at TDC compression so there is no spring pressure to deal with.

Quote
That hotrod guy sounds like Sam Hunt
That show has some interesting episodes. Anyone into Pro Touring cars may enjoy this episode filmed in my home town.
http://www.youtube.com/watch?v=0Gaewg3RepU
« Last Edit: February 07, 2014, 04:31:16 PM by Rikugun »
It is far better to grasp the universe as it really is then to persist in delusion, however satisfying or reassuring.  Carl Sagan

Prophet Of Doom

  • Contributing Member
  • Visionary Grand Master
  • ****
  • Posts: 2734
  • The really perverted one amongst us
Re: Twingle, Twumper, Close Firing V, Big Bang
« Reply #25 on: February 19, 2014, 05:26:25 PM »
I have to say, the sound change is really noticeable now that I've dropped the engine down to 1000 RPM. 

Road test soon

cvincer

  • Contributing Member
  • ROV Full Member
  • ****
  • Posts: 237
Re: Twingle, Twumper, Close Firing V, Big Bang
« Reply #26 on: September 24, 2019, 11:06:03 AM »
PoD......when you did this twingle thing, did you also turn around the sprockets on the ends of the camshafts?

For example (assuming you did it on the front cylinder) in stead of the front cyl sprockets having an  'F'  facing outwards, did you end up with the  'R'  facing outwards?