Going Electronic MK ll

[muskrat]

It might be the nut holding the handlebars.LOL
You'd be getting good at rockerbox replacement by now.
The topic could be split if it goes that way.
Cheers

[Gerry]

Hi Muskrat....it wouldn't surprise me one little bit. No I recon I have missed something within the left side valves, so am going to remove them 2morrow and do a re check. If push comes to shove I'll take it and get the seats re cut ...again as well as the valves faced. The best part is, the bigger the struggle the greater the satisfaction. I did get the seats cut when I first got the head and fitted and ground in new valves. If the fault does lie there then I wont be too embarrassed at all the work I have put into it as I rejected this as a problem but now got no option. I thought it would have righted itself after my 76th birthday on Sunday but no such luck lol. On second thoughts....i'll try the handlebar bolts!!! Cheers. Gerry

[muskrat]

"my 76th birthday on Sunday"
Many happy returns mate.
 

[Gerry]

Cheers Muskrat, Have a good one fella. Have a beer on me :-) Glad I'm not the only silly bugger still mucking about with old bikes. I'd go out of my tree watching tv but I do love what the pc can do for us eh? Gerry

[bsa-bill]

my 76th birthday on Sunday

Congrats Gerry   -  obviously numbers mean not a lot to you

[Gerry]

Many thanks Bill, Muskrat & I, plus many others here on the forum, I suspect, were fortunate to have been born to an era when British bikes were in their prime and I think we are now re living our youth!! Much more important though is the nice people you meet when you are into these wonderful old machines. Haven't come across a nasty one yet. Gerry

[Gerry]

OK guys, Here's the latest......My nephew came round (just dropped in as had business close by) He suggested using washing up liquid around the head/barrel joint, sure enough bubbles on the left hand side!!! Whooray I thought, found the problem. Got the head off....again!! and checked the level across head and barrel. Could get a feeler gauge of 0.005 in but on the right hand of the barrel but nothing on the head, so off comes the barrel and took both to a local engineering shop with excellent reputation and had both faced....0.004" off the head and 0.007" barrel. Re annealed the head gasket and done the re assembly ....AGAIN!! NO CHANGE!!! but this time when I take the plug lead off the right hand side it stops completely, so worse than before. So now I am concentrating on the carb'. It can only be that its not getting enough gas into the near side chamber. Took the 928 carb'. off and am fitting a 930, too big but it may just give me a different result, who knows. Will post the results here shortly. Didn't get the carb'. off my friend's Rocket yet but hopefully I can get it tonight when going to the BSA Club meet with him. Wish me luck fellas I need it bad. Cheers. Gerry

[warmshed]

Sounds like the spark to the left hand side to me, with a single carb I find it hard to believe it would starve just one cylinder.

[warmshed]

Read through the whole thread. I would still suspect the Boyer stator plate. Did you try turning though 180 degrees? Until you have reliable fat spark on both cylinders you should not look elsewhere.  You should be able to turn the bike over slowly and see if you get a good spark from both stator coils. You dont need to turn the bike over quickly as you do with a Mag. What area do you live in, if you are  close I will pop over, two heads and a cuppa often help. I am near the Dartford Crossing. If all fails I have a Lucas Rita for an A10 sitting in the garage, you can use it to pinpoint the fault if required. Dave.

[warmshed]

OOPs just seen where you live, Adelaide is a bit of of trek from Dartford!

[morris]

Gerry,
How about a Colortune? I bought one when I thought having carb trouble, but when checking with the Colortune, I noticed there was a lousy intermittent spark on one cylinder, which made me trace the problem down to ignition.

http://www.gunson.co.uk/item.aspx?code=G4074

[Gerry]

Hi Warm Shed & Morris, Many thanks for your input I really appreciate any help I can get. Well I fitted my mates Monoblock carb off his Rocket this morning and it runs better on the right hand cylinder but not at all still on the left one. Why doesn't this surprise me!!! So it appears that I can count out the carb'. Took the head off again and removed the two valves on the left but can't find anything to cause the problem. I have turned the stator plate for the Boyer 180 degrees and that didn't solve it, swapped the plug leads, tried three lots of new plugs, new leads, plug caps, 4 different coils, had the head and barrel faced, annealed the head gasket. There is good compression on the left hand cylinder - 140psi using the kick start and 160psi when running on the right hand cylinder. Only thing I can do now is try my mates magneto but that's a desperate attempt to solve the problem as I have tried two used mags previous to fitting the Boyer. Will keep you all posted as things develop. Thanks for the offer of the Rita ignition Warmshed, pity I don't still live in St Pauls Cray!! Cheers and thanks again. Gerry

[bsa-bill]

Might be something, probably not though BUT

Last time I had mine out it went lie a dream, started first kick ran like clockwork , so full of confidence I set out for Wooller yesterday started first second kick, first kick it kicked back just a little, ran like it was on one then on the other but not often both, I thought muck in the carb (I've had this before) it settled down after a while but only if on a steady throttle setting any movement of the grip resulted in pop bangs and hicks, got to Wooler, come to go home started first kick but the running was terrible, perceived but it konked out going up hill, coasted down hill and had a look, it started first kick again, I'm thinking maybe timing slipped, or voltage, switched on the headlamp and it was going to stop AHA voltage so sat with it running for a while to put something in the battery meanwhile fiddled with the toggle switch for the ignition it went better so bypassed the switch, started it up first kick again and got home, not comfortably but got home.
Took the seat of and tested the battery 6.5 volts, not good it's a twelve volt battery.
My thinking so far - it might just be the battery in which case the bikes not charging it or I've a short some where possibly the toggle switch.

with a battery so low it's a wonder it ran at all, the batteries are Burlen gel type not supposed to loose there charge and never have so far so I'm suspecting Dynamo or a short

So Gerry I can't recall if you've mentioned battery or not but might be worth checking

[Gerry]

Hi Bill, Yes it is a brand new battery but that doesn't mean I have a good one!! Maybe I'll take it and get it checked out, can't do any harm. I know I couldn't get a spark at one stage and it turned out to be the battery was too low to fire a spark with the Boyer. Gave it a charge up over night and got a good spark. Sounds like the best option at this time. Will see how it turns out. Thanks Bill. Gerry

[warmshed]

Always difficult to solve when you are remote.  But It still sounds like a spark issue. 

When you check the spark, being a wasted spark it is hard to determine that you are seeing both sparks. as you have an issue, you could disconnect the wire from the known good stator coil and see if you are still getting sparks. This would prove you have a good spark at the correct time on the faulty cylinder.  Not having a stator to hand I dont know how easy this would be.
As you say you have reversed the stator, then logically it might be the gap to the magnet gap on the faulty side
Your comment sounds a little too coincidental to me, with the added bonus that if it is this it would be easy to rectify.

", I made a mistake and machined the housing out a bit too much allowing the stator to foul the magnets on the rotor so had to realign the stator by feel which means the magnets could be passing the coil post on one side closer than the other"

Good thought is the harder the fault is to find the easier it is to repair once you have found the cause.

Regards Dave