Try our new info resource - "Aladdin's Cave" (Main menu)Just added a separate link to Ash's Dropbox thread (shortcut)
It'll be interesting to see if there's any improvements by changing the plugs, but think there's potential circumstances under which that would indicate another error.
Michele, a long shot, but is the petcock gauze clear. I had erratic fuel flow and cleaned it in vinegar and very gentle brush with an old toothbrush. Then a column of water from a tap would pass freely through it uninterrupted.I find even when all clean, fuel often only manages to flow through one pipe at a time, so eg from empty, carbs 1&2 and 3&4 don’t both get full flow at the same time, and maybe a slight restriction could cause flow to fluctuate.As I say very much a long shot, but quick and easy to check, and always good to know it’s ok.
Update of the day:Just before thunderstorms hit (although it's still well sunny here) I decided to have a check at the timing.-Points gaps were at 0.3mm and 0.35mm, so I made them both 0.3mm now.-Static timing is spot-on for 1-4 and 2-3I have tried using my strobe but the idling seems too unstable that I am not sure about anything, so I have not tried to adjust anything. I will try again just to see if I notice it being too far advanced at higher revs, but from first examination it does not look that way. It may be that it advances too soon though. I have tried in the past to use different spring combos in the advance mechanism but never really solved anything, so I reverted to the original setup (I was probably jumping the gun anyway).Here's a video I shot today, just to give you an idea of what it sounds like when idling. Note that unless you see my hand on the throttle or idle screw, she's doing everything else by herself!https://youtu.be/ESx_E8mv2vMCarbs are standard PD46A with. standard jetting, This may not be ideal for the Delkevic 4 into 1 the PO put in, but it should not give problems when idlingAs suggested above, I will try spraying carb cleaner on and around the inlet manifolds to check for air leaks there, but I have new manifods and o-rings so I doubt it will be that.
PD46, just about guarantee the pilot jets or pathways are blocked
Small update:Bike runs fine from cold, for about 2-3 minutes. Then, once warmed up, the erratic idle starts showing. I have (abundantly) sprayed carb cleaner on intake manifolds with no change at all, so for now I tend to exclude an air leak as I could not find any evidence of it (and both rubber intakes and manifold o-rings are new).I keep on thinking it could be something in the timing (or rather advance mechanism springs, maybe kicking in too soon) and/or unbalanced carbs (only bench synced visually, with a drill bit).Maybe I'll start playing with the spring combination again, after all I am keeping the original ones as they are and just adding different ones, so anything I do can be undone quite easily.Cheers
This was exactly the same as mine, I sprayed carb cleaner all over and didn’t show a leak but there must have been one there. I replaced the clips with thin stainless jubilee clips. Word of warning is not to over tighten the clips or there is a danger of the clips splitting the rubber.I am convinced you have an air leak. One thing you can try is when bike is running get hold of the carbs and pull/push them up and down. Give em a really good waggle around
Quote from: paulbaker1954 on August 20, 2020, 08:50:40 AMThis was exactly the same as mine, I sprayed carb cleaner all over and didn’t show a leak but there must have been one there. I replaced the clips with thin stainless jubilee clips. Word of warning is not to over tighten the clips or there is a danger of the clips splitting the rubber.I am convinced you have an air leak. One thing you can try is when bike is running get hold of the carbs and pull/push them up and down. Give em a really good waggle aroundOK, that is good info, thank you Paul, I will definitely give it a try. One more question, what do your Jubilee clips look like?cheers
You need 8mm narrow band stainless ones. I got mine from Inox Fasteners in Southampton http://www.inoxbolt.co.uk/zen/index.php?main_page=index&cPath=475_498
Quote from: paulbaker1954 on August 21, 2020, 08:11:40 AMYou need 8mm narrow band stainless ones. I got mine from Inox Fasteners in Southampton http://www.inoxbolt.co.uk/zen/index.php?main_page=index&cPath=475_498Thank you Paul, I have ordered mine! Keeping my fingers crossed it will be as simple as that.CheersMichele
REMEMBER DONT OVERTIGHTEN THEM IN CASE YOU SPLIT THE RUBBERS