Ok guys, I really need some guidance from those who know the BS38 carbs inside out.
I've read the Grizld & 5Twins epic carb guide booklet till I'm blue in the face and I think I've done all the cleaning and checks in accordance with the guide, but I've still got a burp, burp, burping stuttering pilot circuit (at least I assume can only be the pilot circuit at 1/8 - 1/4 throttle and below 3000rpm). Above 3000rpm all seems to work spot on, with plenty of pull right through to full throttle with no issues, hence why I assume its pilots.
The issues I have on the road is the bike stutters and burps annoyingly, while holding 1/8 - 1/4 throttle in say 2nd or 3rd gear, at constant speed. When I try to pull away from standstill the engine splutters and stalls, unless I give it some revs to overcome the loss of power. Its a real pain in the arse.
I was on 42.5 pj's, 130 mains, and the mixture screws were 3/4 turns out. Adjusting the screws made no discernable difference to rpm. Anyway, maybe mistakenly I thought the mixture screws were too closed at only 3/4 turns out, so swapped out the pj's for #40s. I set the mixture screws at 1 turn out, took it up the road to warm it up. While cold the low rev range seems to work fine (did with 45.5 pj's too), pulling smoothly from tickover, but as soon a there's a few miles of warm up the stuttering and burping come back strong.
Once warmed up I tried to adjust the LH mixture screw from 1 turn out, tickover at 1000-1200. Opening it up made little difference till I got to around 1.5 - 1.75 turns out when it began slowing. Closing it down 1/4 - 1/2 turn slowed revs ever so slightly until at closed the engine stops.
Now the RH side is more weird. From one turn out, opening the screw 1/4 turn slows revs but closing the screw, from one turn out all the way through to fully closed continually increases the revs significantly, to around 2000rpm! And then after resettling throttle stop screw and blipping throttle it always keeps hanging, before settling down to 1200rpm.
Frankly, I'm totally lost. There's no-one where I live who will touch carbs. I've cleaned out the carbs (which look very clean anyways) several times now, and carb cleaner seems to be spraying out of all orifices correctly. Float heights are both at 25mm and new float valves fitted. New intake boots and gaskets and blue hylomar used to make sure of no air leaks. So, do I finally have to ditch the BS38's for VM's, which I don't want to do because the bike is totally stock or go back to the 42.5 pj's which were no better? I can't glean anything more from reading, I'm simply not carb-wise, so any help would be appreciated. Please don't reply with clean the carbs again, as I'm absolutely certain they're clean.
I've read the Grizld & 5Twins epic carb guide booklet till I'm blue in the face and I think I've done all the cleaning and checks in accordance with the guide, but I've still got a burp, burp, burping stuttering pilot circuit (at least I assume can only be the pilot circuit at 1/8 - 1/4 throttle and below 3000rpm). Above 3000rpm all seems to work spot on, with plenty of pull right through to full throttle with no issues, hence why I assume its pilots.
The issues I have on the road is the bike stutters and burps annoyingly, while holding 1/8 - 1/4 throttle in say 2nd or 3rd gear, at constant speed. When I try to pull away from standstill the engine splutters and stalls, unless I give it some revs to overcome the loss of power. Its a real pain in the arse.
I was on 42.5 pj's, 130 mains, and the mixture screws were 3/4 turns out. Adjusting the screws made no discernable difference to rpm. Anyway, maybe mistakenly I thought the mixture screws were too closed at only 3/4 turns out, so swapped out the pj's for #40s. I set the mixture screws at 1 turn out, took it up the road to warm it up. While cold the low rev range seems to work fine (did with 45.5 pj's too), pulling smoothly from tickover, but as soon a there's a few miles of warm up the stuttering and burping come back strong.
Once warmed up I tried to adjust the LH mixture screw from 1 turn out, tickover at 1000-1200. Opening it up made little difference till I got to around 1.5 - 1.75 turns out when it began slowing. Closing it down 1/4 - 1/2 turn slowed revs ever so slightly until at closed the engine stops.
Now the RH side is more weird. From one turn out, opening the screw 1/4 turn slows revs but closing the screw, from one turn out all the way through to fully closed continually increases the revs significantly, to around 2000rpm! And then after resettling throttle stop screw and blipping throttle it always keeps hanging, before settling down to 1200rpm.
Frankly, I'm totally lost. There's no-one where I live who will touch carbs. I've cleaned out the carbs (which look very clean anyways) several times now, and carb cleaner seems to be spraying out of all orifices correctly. Float heights are both at 25mm and new float valves fitted. New intake boots and gaskets and blue hylomar used to make sure of no air leaks. So, do I finally have to ditch the BS38's for VM's, which I don't want to do because the bike is totally stock or go back to the 42.5 pj's which were no better? I can't glean anything more from reading, I'm simply not carb-wise, so any help would be appreciated. Please don't reply with clean the carbs again, as I'm absolutely certain they're clean.
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