Definitely incompatible. The full-thread one will hit the piston. If that was in all cylinder heads the engine would probably not even be able to rotate!!!!!!
Yes, 2+ turns out is common on CV fuel screws. By the way, the easiest carbs in the world to tune by ear are Bings on a BM. They should never need to be set by 'n' turns out.
So I went to go do the compression test however the kit that was leant to me does not contain the correct fitting for my 10mm plugs off to Bunnings to try find an adapter edit: Bunnings not super cheap had an adapter so I am stuck
Yeah, what I used to do was basically tune each cylinder by removing the spark plug lead on the other one. Just adjust the mixture until the engine feels like cutting out then do the other one. Then connect both and she (R100/7) ran so smoothly I could stand a pencil up vertically on the tank and it would not vibrate off. I remember going to a vintage race meeting at Oran Park where Don Wilson had a couple of his BMs running next to me and I didn't even know they were running until he told me they were. Just the people chatting around drowned out their motor noise. Don was a magician when it came to BMs.
I can get it to a point where if I hold the starter for an extended amount of time I can get it running and then it will run at very low rpm by itself for a couple seconds then die. This is with choke fully out and idle screw at varying levels including max
Doing that with the choke open for so long can foul the plugs and/or flood the engine... Dry out and clean the plugs, try a little bit of choke (not full) and a little bit of throttle. If it starts to fire, keep everything where it is and hold the button. Very slowly try to roll on the throttle a little bit.
Yep I was just typing much the same .... choke on and hold throttle half open and plenty of starter Im guessing the carbs are way out of sync? Also is this correct? https://2fiftycc.com/index.php?thre...eads-spark-plug-configuration-inline-4s.8176/
Cleaned plugs and started with half choke and a tad of throttle and engine roared to life but did die after a couple of seconds I would have held it however it’s getting a bit loud and these things definitely aren’t quiet. So until tomorrow
Did you poke out lateral bleed holes in emulsion tube and pilot jets with matching size copper wire? Dried petrol varnish turns to plastic and cannot be dissolved with modern carb-cleaner spray that lacks chlorinated compounds. Same with poking out bleed holes in carb venturi. Bend tip of wire 90-degrees 5mm from end and reach down carb throat and floss out all bleed holes (remove AF-screw 1st so it's not blocking hole). You'll find copper-wire pushes out dried petrol plugs from these holes like little grains of sand.
I did inspect all the injectors but I could not inspect the Venturi hole, so I’ll pull the carbs off again and try and dig out if there’s anything there.
I haven’t pulled the carbs off yet but just cranking it, it sounds like it’s so close, like I could hear some cylinders firing but it just never picked up. I’m gonna go through the carbs and clean them as thoroughly as possible
I think its because I had used some carb cleaner on Mmmmm on the plugs and so it used it for fuel. So a complete fluke because I can’t get it to happen again tonight. I am as confused as you are
So I think current issue is one of my carbs (#1) is not getting fuel. Because I’ve managed to “drain” the bowl of carb #1 and comparatively not much is coming out.
Need to split carbs. Scrub out fuel-rails, one going to #1 may be clogged with petrol varnish. Also replace fuel-rail O-rings while you're there.
I assume this comes direct from Thailand, what sort of shipping times are to be expected compared to something like @XCite Bikes being about 5 days. Just because I couldn’t see an option for express or anything like that.