Forum

[John Moulton]

Hi Chris! Good to see that you are making progress. Maybe it is worth checking with Hitchcocks on what jetting they run with the air filter you are using, or, failing that, what air filter/jet combination they recommend. Good luck!

[Alan R]

Hi Chris and glad to see you've made some good progress, but what set-up were you running immediately before you fitted the monoblock ?? You see, the question that your solution raises is }-- why did just the carb change bring on such dire results ?? Surely the previous carb type set-up should have reacted just the same ? ie as if the air filter was blocked.  By pulling the hose off  you've by-passed the air intake and filter system. As John Moulton says, I would re-check your filter/jetting set-up  again. Also, try this }-- disconnect all the tea caddy hoses, clips etc. and remove them all. With the engine running at fast idle,( ie with the bare carb. ) and starting from the CARB. , re-connect one at a time untill the engine falters.  Has something got caught -up in the filter intake ??  Hope this makes sense ??

[simon]

One point I'd make is that you will need to have a collection of replacement plugs around while you get the mixture right. If your unleaded petrol is anything like ours down here in NZ once a plug is sooted up its a goner and no amounts of cleaning will bring it back. The fine soot seems to be far more conductive than the stuff from old leaded juice. You can have an apparently spotless plug but if you stick it on a megger you will see that it will break down under load. This makes tuning doubly difficult as you do have two issues to balance. Interestingly I also found that my 389 was overflowing from the fuel bowl but as mine was a second hand unit I put it down to a previous meddler. I removed the fat fibre washer under the valve cover and that lowered the valve body to the perfect spot. Finally the obvious ones, check that the needle is in the middle position and of course try and set the idle mixture when the bike is hot. The cold setting will obviously be much richer than optimum. Good luck. S

[simon]

One point I'd make is that you will need to have a collection of replacement plugs around while you get the mixture right. If your unleaded petrol is anything like ours down here in NZ once a plug is sooted up its a goner and no amounts of cleaning will bring it back. The fine soot seems to be far more conductive than the stuff from old leaded juice. You can have an apparently spotless plug but if you stick it on a megger you will see that it will break down under load. This makes tuning doubly difficult as you do have two issues to balance. Interestingly I also found that my 389 was overflowing from the fuel bowl but as mine was a second hand unit I put it down to a previous meddler. I removed the fat fibre washer under the valve cover and that lowered the valve body to the perfect spot. Finally the obvious ones, check that the needle is in the middle position and of course try and set the idle mixture when the bike is hot. The cold setting will obviously be much richer than optimum. Good luck. S

[Alan R]

Hello Simon--- Yes, that fibre washer is what the BSA chap had trouble with. Have a look ,  it's good reading. Best regards   Alan R

[Chris Tindal]

Alan R, I've read the threads on the BSA website and yes it's interesting reading. The previous carb was a Mikarb that I spend weeks getting right a couple of years ago, so maybe I was foolish to expect to just bolt the Amal on. They are, however meant to be about right for an unrestrictive pancake or old style tea caddy. The symptoms were rather odd and varied though and that's why I couldn't work it out. Thanks for all the advice chaps.

[Alan R]

Hi Chris  glad to have been of some help. As mentioned elsewhere I fitted a Mk1 Concentric (supplied by our hosts) onto my then Bullet Sixty Five and apart from an unrelated fault with the float, had absolutely no probs . at all. That was fitted with a paper element pancake filter and bolted to our hosts adapter flange plus insulator. Norh Wales, London, Solihull(International), Gloucester, daily for work..... NO PROBS.  Can you remember your jetting, slide etc ?? I'm trying to do the same with my Mikcarb but just can't get it finally set ok.  (2005 Bullet 500 classic). 

[Chris Tindal]

Alan R, from memory it has 117.5 main, PO needle, 27.5 pilot and richer 2.5 slide. It took a while but I almost eliminated poping and stalling at the lights, I said almost! The richer slide made a significant difference to poping back and with this set up the plugs a chocolate brown with steady tickover and it runs well.

[Alan R]

Cheers matey--- I'll give that set-up a go this week. I might have a go at painting the Bullet as ------The Ghost Rider's Apprentice !!! Getting the old leathers to burn shoudn't be any probs.

[John J]

Hello Alan R, I have a 2008 500 Classic Bullet. I have fitted a free flow exhaust and an Indian short silencer. I have also removed the filter and fitted a bellmouth. My carb settings are, pilot30, needle jet 04, Needle clip 2nd posn. main jet 135 float height 23mm. The slide is a 3 but the cutaway I modified to about 2.5. The bike runs like a dream and if crouched will do a geniune 80mph with good acceleraion to boot. This is with an 18T sprocket. The Mikcarb can be made to run very well and mine stays in tune.