Author Topic: 59 A7 starting problems  (Read 3831 times)

Online bsa-bill

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Re: 59 A7 problems
« Reply #15 on: 14.12. 2013 15:19 »
Quote
including one of those Viton tipped needles

could be a factor, off the top of my head I can't remember which is right but some carbs have a fibre washer under the fuel filter housing on the float chamber and some don't, I'm thinking along the lines of float height, if yours has a fibre washer remove or fit one if it hasn't
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline Gasket4450

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Re: 59 A7 problems
« Reply #16 on: 14.12. 2013 15:43 »
I would concur with the retarded ignition timing prognosis. Last time I timed my bike, the magneto pinion must have slipped or moved (that's my excuse, and I'm sticking to it) when I put the timing cover on. It was also misfiring and not responsive to the throttle. It could be something as simple as that, as our engines aren't too complicated, and if your getting fuel and sparks, the next logical step it to ensure the sparks happen at the right time. Could you have timed the engine after tdc instead of before tdc?

You must be close to a solution, as there's only a few variables that can alter.

         Aha ! Now, here's a thing. When I tightened up the sleeved nut in the centre of the advance/retard mechanism, it didn't feel quite right, as though it was about to let go, or strip the thread, so I didn't do it up to 10,000 lbs of torque like you are supposed to.
I wonder if it is slipping on the armature spindle ???  The A/R unit was second hand when I got it, so I wonder if the spindle taper doesn't match the centre of the A/R gear ? I have had to lap two together in the past to get them to seat properly. Following on from that, does anybody know, therefore, if it is possible to buy a replacement nut ? I would think it is more likely to be the nut than the threads on the spindle. Maybe a spoonful of Bearing Fit would help ?
          However, having thought about that, I think those nuts perform the job of a self-extracting puller on the A/R, so I suppose they must be conical in shape - does that mean I have to dismantle the A/R mechanism to get a new nut in ? *conf*.
          I may revert to a manual mag that I have hidden away in the loft somewhere, as I see that second-hand A/R units are selling for prices in excess of £60 - £70 on Ebay UK. God knows what a new or refurbished one would cost.



Quote
including one of those Viton tipped needles

could be a factor, off the top of my head I can't remember which is right but some carbs have a fibre washer under the fuel filter housing on the float chamber and some don't, I'm thinking along the lines of float height, if yours has a fibre washer remove or fit one if it hasn't

Thanks Bill, good thinking. My fuel filter has no fibre washer under it, as I always thought they were meant to be that way to avoid altering the height of the float needle seat. However, I reckon that would certainly restrict the fuel supply, so may try one and see what happens !

Regards
Norman
1960 A10, alive and thriving. 1959 A7 living on borrowed time !

Offline shabashow

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Re: 59 A7 starting problems
« Reply #17 on: 16.12. 2013 18:56 »
If I was a betting man I'd put some money on the timing having slipped. You could take a spark plug out and insert a straw or similar and see how much before (or after  *conf*) tdc the points open out. There are settings for the fully advanced timing (11/32" for my Golden Flash) but I haven't seen any data for the 'normal' retarded timing. I'm sure that info will be buried in the vast archive of knowledge in this formum, or someone who's measured it will pipe up with the figures.

Of course, you could take the timing cover off and wedge it full advance to confirm. Not a big job, really, and shouldn't take much time.

I think taking the A/R unit apart would be difficult for me, as its riveted together. I sent mine off to get refurbished when I rebuilt my bike, I think it cost £45 or so, but that was a few years ago.


Online bsa-bill

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Re: 59 A7 starting problems
« Reply #18 on: 16.12. 2013 20:46 »
Quote
someone who's measured it will pipe up with the figures.

Well I haven't measured it but do recall having a mild heart attack when strobe checking my timing on the Rocket God flash and saw it firing at TDC then remembering it was ticking over so was retarded, a blip of the throtlle returned heart beat to normal.

Not too precise folks but would think if using the straw or pencil down the hole method if points are opening at TDC retarded (both sides) it should be within range of running reasonable
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline duTch

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Re: 59 A7 starting problems
« Reply #19 on: 16.12. 2013 22:08 »

 I'm a bit lazy, so the last few times I've tended to the timing (while sorting out the cam ring to even up the gap), I just pushed the points around to advance with my finger- seems to work ok
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
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Offline Gasket4450

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Re: 59 A7 starting problems
« Reply #20 on: 17.12. 2013 00:23 »
               Shabashow, the more I read, the more I believe you are right - it must be the timing slipping. After all, if there was something inherently wrong, the engine shouldn't run at all, should it ? I am thinking that if it runs as though the timing is way out, but does actually run, then it probably is the timing after all. I'll take the cover off and wedge the A/R in fully advanced and check, and let you know. Unfortunately won't be for a little while due to a little bit of a  ' ....right wrist contacting ground at speed on unexpected wet leaves...... ' scenario !  A10 with dented headlight rim and shell, battered front mudguard, bent gear lever and footrest, and twisted forks. Hey, ho, nothing that can't be put right though. ( Could have happened to anybody, I told myself. Doesn't make you feel any better, though, does it ??? ).

                Bill, thanks once again for your help. I have one of those little screw-in TDC gadgets, with a central sliding bar already marked off at 5/16 BTDC, so should be able to work from there. Would I be right in thinking that, as a rough guide, the points would be fully open at .012 thou at TDC ? I'm also beginning to suspect unequal cam ring shoulders, so something else to check.

                Dutch, yes I have used the  ' pushing with finger ' method in the past, so I know where you're coming from with that one. I'm obliged to you .

                My thanks to all of you who have stayed with this tale of woe so far.  I read nearly the entire ' Engine ' section of posts last week, so I know I am not the only one with starting problems  (.......funny, my wife's been saying that for years......never knew what she meant 'till now....!!!!!).

Will report later, when I have two working hands again
Regards,
Norman
1960 A10, alive and thriving. 1959 A7 living on borrowed time !

Offline Topdad

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Re: 59 A7 starting problems
« Reply #21 on: 17.12. 2013 12:32 »
Good afternoon Norman, been following your post with great interest but felt you were getting such good advice I'd keep stome . I'm , for my sins ,a confirmed "pencil down the plughole  " timing type person ( for timing A10's only!! he added quickly ) and thought I'd chime in now ,hope you don't mind. With her set to 5/16" btdc the points should just be seperating ,hence the fag paper between the points tag that you hear mentioned (after checking that the points are open ing to 12 thou each side etc) and that should do it so you can do your strobing .\\\\\\\\\\\\if you are goingdown that road  I'd recommend a mod by one of our gurus who elongated the fixing holes of the mag body ,so that it can be turned to adjust as per the strobe ,wonderful simple but effective mod ,think it was Orabanda who did it ,if not apologises to the rightful genius .That won't ofcourse help until shes running first so hence why I've suggested going back to basics then take it from there ,best of luck BobH. PS sorry to hear of your "off" happened to me a couple of years ago ,lowspeed but on gravel not to be recommended same sort of damage ,thou mostly hurt pride ,had an enormous brouse on by thigh ,had to tell the wife I'd banged it on the workbench or she'd have had me wrapped in bubblewrap everytime I wanted to go for a ride after!!
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Offline muskrat

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Re: 59 A7 starting problems
« Reply #22 on: 17.12. 2013 12:49 »
G'day Norman. Those tdc tools give a false btdc reading due to the angle of the plug hole.
While you've got the spanners out remove the primary cover and make up a timing disc and pointer (mine is in 5 degree increments, see pic). Use the tdc tool to find tdc and mark the disc at the pointer. Mark the disc at 30 and 35 degrees. Use a timing light (strobe) with an external 12v power source. With the plugs out but earthed and timing light pick up connected to one, get a mate to kick like mad and watch your marks. With the auto advance left in the retard (wife recons I'm one) position it should spark at between 10 and 5 degrees before tdc. Swap to other lead and note any difference (cam ring wear).
The points will be fully open at about 20 degrees after tdc.
Cheers
Just saw Topdads post. Yes it was Orabanda's mod.
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Online cyclobutch

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Re: 59 A7 starting problems
« Reply #23 on: 17.12. 2013 15:16 »
But if we knew the angle of the plug-ole we could trig it ... ?
Various, including ...
'58 Iron Head Flash Bitza


Offline Gasket4450

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Re: 59 A7 starting problems
« Reply #24 on: 17.12. 2013 17:12 »

  Hello Bob,
                         Always pleased to see a new face on this long-running tale of misery. Thanks for your wise words. Yes, I had the same black bruising down the right leg, had to wear jogging bottoms with dressing gown for a couple of weeks so as to avoid rousing suspicion ( ....yup, I've got a bubble-wrap missus as well !!! ). Yes, seen that magneto mod, elongating the holes either side about 1/16" so the mag can be moved slightly when running, a bit like a manual A/R. I think at the end of the day I shall swap my re-con armature over into a spare manual mag which I have, which is in good nick.

  Musky, does the angle of the plug hole make such a difference with the TDC gadget ? I reasoned that moving 5/16" sideways would probably equate to no more than 3/8" straight up anyway, so I would be safe. Perhaps I'll dig out my trusty pencil with the penknife marks which will stand upright, then ? I have one of SRM's ready-made discs, so will try that, as it appears to be the only trusty way to do it.
             I will, however, start again from scratch.  Just a thought - what does the oft-used phrase  ".....timed 180 degrees out ...." mean ? If I am going back to lining up the timing marks on the pinions, can it only be done when the right hand cylinder is on TDC on compression ? Or does it not matter as long as crank, idler, and cam marks are all aligned ? Does the  " 180 degrees out " refer to valve timing, or the position of the points in the end of the mag ?  When setting my points, I have always used the right hand cylinder at 5/16" before TDC, and checked the points which are roughly in the 5 o'clock position, i.e. just before the heel moves on to the widest part of the cam, using a .002 feeler gauge. Can't afford a strobe at the moment, as just bought a Colourtune gizmo, in case my plugs are not performing under pressure ( ...bit like me, then... ). I had one donkey's years ago for my Ford Cortina ( ...remember Cortinas, some of you other old Greybeards out there ??? ), and I remember they were an excellent bit of kit.

Regards
Norman

 
1960 A10, alive and thriving. 1959 A7 living on borrowed time !

Online bsa-bill

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Re: 59 A7 starting problems
« Reply #25 on: 17.12. 2013 20:56 »
Quote
.timed 180 degrees out

Means the plug leads have been swapped around

Now just to perhaps input a bit of realism, the slope of the plug hole will make a difference - a small difference as will the backlash on all the gears that drive the magneto as will the tolerance allowed in the build of the A/R unit and the eye sight of the tuner and even the thickness of the pencil used to mark the stick stuck down into the cylinder.
all these small things can add up one way or another but in general BSA made bikes for Joe Bloggs to ride to work on all week and tune with his fag papers  if he needed to while his wife made Sunday lunch, the bike would run if he was anywhere near right.
Some may point to he fact that most of the time any backlash will be taken up, this assumes we are in acceleration all if the time, not true most of the time while cruising we're on a steady throttle setting and the backlash will shift one one extreme to the other with every overrun
I have a notion the best tuners are to be seen track side blipping throttles and staring into the sky (you've seen them) but listening to the engine.

All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline shabashow

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Re: 59 A7 starting problems
« Reply #26 on: 18.12. 2013 20:16 »
Sorry to hear about your acrobatics, and hope all heals up ok. Sounds like a desperate attempt to get out of decorating the christmas tree  ;) Too bad our machinery wasn't self healing (though I believe 'smart' plastics are in development which can self repair minor tears - hints of star trek science or witchcraft!) Anyway, back to topic - I raid our kitchen drawers for a wooden kebab stick to do my timing. I bend a couple of bits of wire into some small loops to keep the stick upright and put a pencil mark at the appropriate distances. I then put the bike in top gear and use the rear wheel to rotate the engine, going in the normal direction to get tdc, then rotate the wheel back to below the timing mark to take up any backlash, then slowly forward again to stop just when the mark is correct. Then I move the points hither and thither until the thinnest of fag papers just starts to release. Rizzla blue or silver are the thinnest, I think. If you want to check the timing of the other pot, repeat, but this time make sure the points are on the opposite side, i.e. when the other piston is firing. I think the lower HT lead goes to the right pot, but to be sure, disconnect the ht lead from the mag. If you see the brass bit in the slip ring, that HT lead is the one that will be sparking. I'm 99.99% confident that once you get the timing right (and make sure it doesn't slip again) you'll have a bike that'll start first (or at least second) kick.
John

Offline wilko

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Re: 59 A7 starting problems
« Reply #27 on: 18.12. 2013 22:33 »
And in future don't listen to anyone about maggy overhauls until you've tried everything else. I've only had one done in 40 years.

Offline Gasket4450

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Re: 59 A7 starting problems
« Reply #28 on: 19.12. 2013 10:29 »
           Great News, Great NEWS !!!  *yeah*   No, not the Second Coming, but nearly as good. I have been wielding the spanners as best I can, and have finally confirmed what I think we knew all along. Apart from taking the covers off ( and destroying my lovely oil-tight gasket work again .... ) to check timing marks, which were spot on, I removed the magneto, taking the auto advance retard unit off the end of the armature shaft. I removed the armature from the mag, and replaced the A/R unit on the shaft without the nut, and gave it a couple of sharp taps with a hide mallet to seat it on the taper. I turned the armature upside down in my hand, and what do you think happened.....? Yes, you guessed it, the A/R unit just dropped off the shaft.  *eek*. Top marks to all of you who saw that one coming!!!  
             I tried it again to make sure, this time giving it several clouts with the ubiquitous mallet to seat it properly, and the same thing happened  *problem*. Well, well, well, I thought. Obviously there was enough initial grab with the nut tightened up to stay in the correct position until the engine fired up, but then centrifugal force took over and moved the pinion on the shaft, altering the timing drastically.
        So, it appears that although the A/R unit seemed to be secure when I tightened up the sleeve nut, it wasn't seating on the taper at all. I have attempted to lap them together with fine grinding paste, but to no avail. I have now junked the A/R unit, which was a
'Fleabay' special anyway, and will install a refurbed manual unit after the festivities.

         Shabashow, was my ploy to get out of hanging flashing icicles from the roof that easy to see through, then ???? Always worked in the past. Thanks for your advice. I use the ' back wheel, gearbox in 4th ' method to rotate the engine by small amounts as you suggest, and I knew about seeing the brass contact on the slip ring through the pickup hole from the pages of this Forum, but I think we may be almost there now. Never thought about the kebab stick, though, brilliant idea.

          Wilko, I guess you must have been lucky to have a mag last that long, and it was my fault for buying untried goods on Evilbay, the ' Bay of Fools ', as my local Brit bike shop proprietor calls it. In fairness, my mag did have a failed condenser, which would have caused me problems anyway, had it not been discovered, so paying out to have it put right was worthwhile in the long run.

           Now, if only I can work out how to post pictures, I 'll put my pride and joy on for you all to see (....this thread has been running so long, some of you think I don't own a bike at all......!!! ), and maybe post a link to YouTube for the first successful firing up when it happens  *beer* .

My thanks to all involved in this long-running saga ( ...been running longer than ' Home and Away' by now. )

Regards
Norman  
1960 A10, alive and thriving. 1959 A7 living on borrowed time !

Offline Topdad

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Re: 59 A7 starting problems
« Reply #29 on: 19.12. 2013 11:47 »
Don't you just love a happy ending!!!  Really glad your persistence paid off and Johns final advice speaks volumes about these bikes of ours and poss a few roadside repairs without any fancy tools and has a nonsmoker found the only usefull purpose for fag paper ...between the points ,best wishes BobH.
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