hi , just wanted to know if this happens to any one else .......

Cold morning ...i let the bike warm a little, then take off ..sure the gear box is a little tight , but all is good by the next set of traffic lights

Warm afternoon ..bike sitting for 8 hours ...start up ..do all the same as a cold morning ......BACK FIRE , FARTS , SHITS IT SELF , wont run properly ...but after 5 more mins of warming up ...runs well . This has happen twice now , all on a warm after noon too .

Q 1 ...is this vapour lock ??????

                               thanks guys , any imput will help

                                                                      Timmey the un-cool with farting bike !!!

hi mates iam from the states here and iam gonna see if i can bring my dead head back to life here as my '92 evo had to sit for some years and iam in the process of bringing it back to life so my knowlege may be a little rusty so feel free to correct me anyone please but i do think iam correct on this.HD plugs are made by champion so thats why alot of us get the same results when using HD  or champion this iam pretty sure iam remembering correctly. 2nd, if i remember right i was told that the NKG plugs are (and i maybe wrong as it's been awhile since i've had this problem) made for nissans. and something about the plug doesnt run well or last long in our HD ,the evo's anyway as iam famialar with the  twin cams or any of the computerized bikes,just not my gig. iam running a SS E CARB,DAVE MACKEY HEADS,SS PISTONS AND A LINE WEBBER CAM,heads & cam match set.so the bike is set up pretty strong and i run BP 91 OCTANE fuel. yadda yadda, i was having simular problems with the nkg plugs & wish i could remember all the info i learned  about those plugs but i know i did learn that i never ran them ever again. i think mate you may be fouling those nkg's out and they are going to continue doing so from my past experience. cheers to all & hope this helps and i thsnk you mates for allowing me to be apart of your forum as i have seen alot of knowledge on here,cheers 

G'day Timmey,
Have a go at this, change over you lights circuit breaker for your ignition circuit breaker (under Dash in a 92 heritage.)
If it fixes the problem get a 15 amp circuit breaker and replace the dodgy one.
Cheers,
Cris.

ngk plugs are the best plugs made i have been using them in my bikes+cars for 20years from wipper snippers to  mates 7 sec cars and are the world leaders in that field .nissian use nippon densso  as oem ,  seen ngks do  80,000 + ks in taxis not platnum  std , i have had the same set in my bike for 4 years once a plug is fould it  it will not un foul completley  anless removed and sand blasted cleaned  or for  $10 bucks a new set,bosch make alot of other great electrical parts but there plugs are shit and most auto workshops will not use them .i beleave you are on the right track with the choke try no choke  two half  twist and start when cold if your tune is close to being right.my 2cents................

i had exatly same problem i had ngk iridiam plugs i put my old one back in and it fixed the problem  ive since returnred the ngk iridium plugs and got more ngk iridiums and so far ther fine i must had some doggy plugs  mine running fine now even on cold starts etc problem fixed.

try new plugs.

and my bike was 1994 heratge softail. evo 1340

update....  my 2nd set of ngk iritiums have just shit it too so must be that my bike hates theas plugs as befor put the origanals back in and runs perfect againg  im just guna stick with standard ngks as thay seam to be fine . bugger the iridiums.;

Hey Timmey, well that choke is not really a choke it's a mixture enrichment, but on the shorty E & G s also speeds up idle, you don't ride with that turned on for too long , when i use my S&S carbs i pull that out when they are cold, start up then turn off hold rev with throtle @ about 1,500 till motor warms up to the touch, then she is on full torque as everything expands as they warm up, then when she is warm, i ride off not before, ive always done it that way. i just use champion plugs, i thought NGK were jap? but i've got a Jap CV carb

hope you solve the problem, with those S&S, ( also should do this with most carbs ) you just roll the throtle don't wack it open fast or she will fart i'm sure. just how it is , plane and simple no lap top needed.

cheers