Hello all,
For the past 7 months or so I've been restoring/rebuilding a 1964 Thunderbolt Rocket from what basically was a pile of rusted parts. I've got to the stage of firing her up for the first time but she will just not start. Not even a pop, spit or bang.
The bike has been converted to 12V and is fitted with a Pazon Sure-Fire ignition system running two new 6V coils in series.
The timing marks on the gears all lined up correctly when I re-assembled the engine and I'm getting healthy sparks at the plugs when they are out and touching the head.
The Pazon is set up correctly I'm sure. 9.1mm BTDC and the dot lines up nicely in the hole on the trigger plate. Even if the timing was a little out I would have thought there would be signs of life.
Both plugs/caps/leads have been changed, compression is good.
I can see the valves opening and closing through the plug hole.
The bike is fitted with a new Amal 389 Monobloc correctly jetted. It seems to "suck" ok when kicking over, but even after a good tickling the plugs remain dry and there are no signs of fuel on the piston tops.
I've even tried "easy start" directly in but not a peep.
I'm baffled now. I must be missing the obvious but I can't for the life of me see what.
Your thoughts on this would be greatly appreciated!
Cheers.......................Shaun.
Is it possible to set the timing 360 degrees out, just thinking of things I have heard back in the old days. Just wondering if it is sparking on exhaust cycle or do these have wasted spark. Sounds like timing to me ? Keep updating ?
if the plugs are dry then that is where i would start, remove the plugs and try adding a few drips of petrol into each cylinder, replace the plugs and give it a kick.
If there is still no bang at all you should then look at ignition timing and possibly valve timing although with these both out you can still get a pop or a bang.
;)
Hello and thanks for your reply's.
The Pazon ignition system is the "wasted spark" type so can time up on either cylinder?
I'v put both Petrol and easy start directly into the combustion chamber - nothing.
Sure the timing is okay, and as you say even if it's a bit out I should get something.
Cheers........Shaun.
:)
Shot in the dark---very recently on here someone with virtually the same problem had a duff set of brand new plugs. Sparked OK in the open but not under compression.
Mike 8) 8) 8)
having fitted many plugs for customers, Ive only ever had one plug supplied a failure. its possible, but two in the same batch...
when I had a Vauxhall Viva, first car, I cycled 5 miles each way 4 times in the same day just to get a condenser that worked. In the end the autoparts shop gave me the card of condensers and told me to bring them back when I found one that worked. They were the good old days!!!
valve timing will probably spark in manifold or exhaust..
Easy start normally works, my guess is like the WD B33 Im working on, same as the AJS Stormer I used to race, crankcase pressure. the AJ wouldnt run if fuel mix too rich and took up space under the crank so had to be drained, likewise Im getting a lot of friction (could be crank pressure) trying to kick the B33 . My A7 wont start if it has wet sumped........my best guess.
Hello and thanks for the replies,
On second set of new plugs now so hopefully not that.
Not sure I understand the crank pressure theory. Are you suggesting it might already have wet sumped or the mixture is too rich?
Cheers.........Shaun.
https://www.burtonpower.com/tuning-guides/tuning-guide-pages/engine-breather-system.html
I remember there is a vent disc and spring on the A65 cam shaft, some people leave off others on.
have you checked compression
When I first started my DB500 I must have kicked it over 200 times checked compression checked timing . Valves and ignition . It wouldn't start , had new carb , piston , valves , crankshaft , camshafts , bearings everything was right . Late at night I decided that this was the last kick of the day and bang straight into life . I didn't even have to adjust the carb it just ticked over . Now it starts first kick , touch wood , . If I had bothered to look at the internet and read the starting procedure for a gold star I would have saved myself a sore leg , and head , and 4 hours of checking . So could be nothing at all but process of starting . Have a look at the good old internet on the starting procedure .
Hello and thanks again......
Chaz, there is a breather disc/spring assembly on the end of the cam. Compression seems very good, although not tested with a gauge only the right boot.
Duc, this extract from Brit Bikes Forum seems to sum it up. "When we say that these Brit bikes have "character" very often it means that although ostensibly identical they can require different treatment to start and run properly".
I've had all sorts of classics over the years virtually all with Amal carbs and they've mostly needed a different technique to start them. My 64 A50 just needs a tickle, a prime kick and then she's off first or second go.
I've trawled the net. There are so many different ideas on how to start various types of bike.
It might be a good idea though to jot them all down and work through them one by one!
Cheers........Shaun.
a second opinion is always a good idea, whereabouts in the country are you? i am sure somebody would be able to help if close enough.
:D
Hello Derek, thanks for your reply,
A second opinion and a look see would be most welcome, the kettle's always on!
I'm in Rushden Northants,
Cheers.....Shaun.
:)
Not Toooooooooooooooo far from Glasgow then !!!!!!!!!!!!!!!!!!1
Mike 8) 8) 8)
drained the sump, loosened the 4 nuts and let out around a pint of oil in the M20/B33 today. let it drain while sorting out the feed to the carb....
carb has a reservoir (276) and wasnt filling more than bottom hole. disconnected and moved pipe then free flow. carb float is , I think clipped too low, filled reservoir, replaced dry plug after a couple of kicks over tdc have had the bike running a couple of times.
need tooo...
get new plug
see owner about carb, well worn and float clip soldered to float.
plug is rich and looks like piston is coated in carbon, reccomend a decoke.
as plug was one supplied, wouldnt start on easy start only other thing done was drain sump. its easier to kick over now as well.
When I finished restoring my A10 Plunger it would not start. So me and two of my younger friends tried to push start it many times on the long bank outside my house. When we were all worn out we bumped it for the last time and it popped and banged and fired a bit but did not start! I rolled it in the garage and we all sat on the floor panting. 20 minutes later the lads were ready to go. Paul just walked over to the bike and kicked it. IT STARTED! It has started 1st time ever since and runs like a switch watch. So don't give up and try push starting.
John.
Hi Shaun, fellow A50 owner.
My old A10 had a similar problem. There was a plastic stop valve actuated by the float chamber to halt the flow of petrol - which did not function.
It's identified as the float needle 376/089.
As the chamber fills, this pointed stop valve is lifted up into a recess. This little devil was sticking in the 'stop flow' position. Tickling didn't work.
So, try stripping float chamber on carb, check that this little, pointed stop actually moves freely in its channel.
Whilst you've got the float chamber cover off, check that the float actually moves up and down on its shaft and that this actuates the float needle open and closed.
Another thought - is your petrol 'fresh' Sometimes old fuel or low octane stuff just doesn't want to burn.
Hi all and thanks for your replies,
Johnjag, I agree that bumping might well help, Will give it a try tomorrow although I won't be pushing it too far till I'll be out of breath!
Splodger, I assume you're talking about the float needle sticking. The carb is brand new so not too keen to disturb the float chamber cover, I'm hoping that the float needle isn't stuck but if I have to I will take a look. Don't know what type of float needle they put in new carbs nowadays they used to use plastic ones but there are brass/aluminium/Viton tipped ones out there.
For all who have been following these posts, today I've checked the static and inlet/exhaust valve timing with a degree disc and it's all good.
My good mate and I did find however that we had a weak spark again when cranking with the plugs out. I've fitted a brand new Pazon system. When flicking a magnet over the coils on the trigger plate we get a fat healthy spark. Same again when we flick the trigger wires together quickly. I did notice that the magnets on the rotor are somewhat recessed. I don't know whether this is causing the weak spark or not. I would have thought that it would either trigger or not, I just don't know.
Decided to bite the bullet and fit a Boyer Mk4 tomorrow hopefully.
Will keep you posted............Shaun.
Last year I was summoned to my mates cave. A gentleman had just turned up to collect his new A10 and it would not start. We had a good spark and petrol came out of the tickler. Beyond that I found out that the fuel tank was empty. 5 litres later and it started first time. That few drips of fuel in the pipe totally had us over a treat. Never stop learning !!
Hello all,
Had another bash at starting the old girl today.
Fitted a Boyer MK IV yesterday morning and got sparks but still wouldn't fire.
This morning timed her up using a timing disc and piston stop, spot on.
I then fitted a dual output coil kindly lent to me by a member. A few kicks and she kicked back viciously. It spat and kicked back a few more times but still wouldn't run.
Decided to bump start it on the small road outside my house. Had three good pushes and she popped, spat and fired but still wouldn't run
Getting too old for this bump starting game - out of breath in no time! Need a strapping youth or a roller starter next.
Progress has been made I suppose, at least she's firing fairly regularly now.
Will keep you all posted.
Cheers........Shaun.
Hi Shaun I have the same electrics set up and same make. You will need to do it on a timing light as per Boyers instructions. They have a really good website with a fault finding section. Glad you are making progress. Try to retard it manually at first !
Shaun,
Is the battery fully charged? If the voltage is low, the advance curve on the Boyer advances so it will kick back when trying to kick start it and if you do get it to start can spit back.
Just a thought!
Chris
Hi all thanks for your replies,
Chris, battery voltage at 12.38 volts after charging. Do you reckon this is too low?
Cheers........Shaun.
Hello all.
She runs!!
Went out this morning with my good mate and tried again.
About 10 kicks she spat. Next kick off she went like a good un'.
Sounded all good, good oil return, let her warm up for a minute or two then a quick throttle stop and idle mixture adjust and she settled down to a nice even tickover.
Didn't want to turn her off but let her cool down for a while and tried again. Took a good few kicks but off she went again.
Have stopped and started her quite a few times now and it's getting easier.
Ducati2242,s post hinted at starting procedure - He's right. This is a different animal to my old lazy low comp A50 which always starts on the button whatever you do. I know a lot of bikes have their own peculiarities on starting and this one's going to be no exception.
I will learn it though.
I reckon there were a few issues that i had to sort before she finally ran, the turning point however was the fitting of the dual output coil kindly lent to me by a member. Soon as it had been fitted she began to come into life.
Johnjag's post spurred me on. Don't give up!
Going to hopefully ride her to the National Rally in May.
Thank you all for your helpful posts.
Will keep you all updated.
Cheers............................Shaun.