Misc: Everything Else Starting Problem - Series 'C' BIG Single

[Jez Nemeth]

Very kind of you to say Bill Sir -but we've all made this work, and I don't fully feel I own it bizarrely, more of a 'care-taking' role with this engine. Its a bit of motorcycling and Vincent history -I really had no clue when I went down to Shepton Mallet to the Classic Bike Show, met Eddie -I'd be buying it -but it made sense in the moment. Put together a running Comet engine once before -but most of the rules here don't fully apply -Knew very little about setting valves and so on -just trust you'll learn to overcome obstacles don't you?

You suggested it to me of course Bill, and there was a chap there looking through John Newson's stall outside, and I'd been talking with John about the engine, John turned to deal with a customer -this guy looked at me square and said in a lilting Irish accent - 'Would you regret not buying it? We're only here once -go on do it!'

Would have loved to have met the bloke though -do feel a sense of respectful honouring of John's passion by all of us, advice, offers of help, many pm's of support and acknowledgement of what it is -he might be surprised by that.

Using this engine, and hopefully in the future with the intent of even running it in anger...yup that would have amused him I agree. Objectively it amuses me.

Anyway it's all fun isn't it?

 

[Bill Thomas]

And Graham must take Credit for knocking up this Forum,
I would never thought it possible to talk to people all over the world .
Magic !!.

 

[Jez Nemeth]

Agreed, Graham -you're a star mate! And for flipping this thread over from 'A' Series 500/1000's -thank you.

Just a thought...might it be worth letting Eddie know about the bike's existence?...They we're clearly such good pals

 

[Peter Holmes]

Jez, I have no idea why your bike is a recalcitrant starter, I would check that your battery holds 12volts+ overnight, also my view of most modern spark plugs is that they are mainly not suited to old motorcycles. I was once a sucker for most things modern, as far as spark plugs go anyway, so when Big Sid recommended Nippon Denso plugs, I duly went out and purchased a set, I was not impressed, likewise Bosch, NGK and a plethora of other modern plugs, Iridium etc. all with fancy claims and names, but my plug of choice, that has never let me down over thousands of miles in Rapide and Comet is the KLG FE 70, as I said, when I am home I will send you one to try and keep, at least that will rule out the plug as the possible cause of your difficulty in starting.

 

[Jez Nemeth]

Another thought -off piste again. Gardner Carbs, better than the 1000 series 1036 I'm presently using- designed for racing, let's say for Sprint racing? And with that I'm assuming power rollers best way to startup.

Just caught that message Peter -many thanks -that's appreciated...I feel like with a kid we're in very early days but starting to get into dealing with and refining teething troubles...

 

[Bill Thomas]

I have had 3 sets of Gardners They are good for power , But they will drive you MAD.

A trick if you think you have flooded it, Switch the petrol off,
And after a few kicks it might fire up for a few seconds ,
If your quick you might catch it and get the petrol back on,

Or some people switch the petrol off and lift the valve lifter and kick it over a few time to clear the petrol.

Had a good one on youtube the other day, A chap with a Norden, Drove 800 miles with out switching the petrol on,
Conked out on the bypass , Waited for 5 hours to be picked up !!.
New bike , Nobody told him he had a tap !!,
Other people have had the same problem !!.

 

[Peter Holmes]

800 miles without turning the fuel tap on, now that is some float chamber, what is it, a bucket?

 

[greg brillus]

Jez, Some of these engines dont like to start by simply turning the engine just over TDC and then kicking........This can depend on the gearbox used as well, but some like the engine tuned over more, and then kick.......that is, if you push the lever at the top of its stroke, to go just over TDC, continue pushing the lever down more.........re set the lever up again, and then kick.........One other large issue as well, if this engine was one of JR then it could have one of his big cams........If its anything like the one in my racer, the duration is massive.......The inlet closes not more than 80 or less degrees before TDC and they have a huge overlap.......this means that part of the intake charge is being pushed out before it gets drawn in........So that could make starting difficult as well........It will come down to some careful but simple settings, but probably just technique to start it every time..........My Rapide has quite big cams in it, and it needs a good firm kick to start every time........If you use a lazy kick on mine you will be there all day trying.........The joys of hotted up engines........All good fun.......Cheers.

 

[Monkeypants]

A twin with big cams sounds lumpy at idle. It's very different from a Rapide with MK1s or Mk2s. The idle is consistently inconsistent.

What happens with a single?

Your engine in the video sounds quite similar to a regular 500 at idle, maybe louder but also very even.
Was the engine built for road or race?
I don't know how you manage to kick it over. I have quite a time with the 1360 which is 680cc s per pot. It has big cams which ease the kickover a bit.

Any idea of the CR on this engine?
Glen

 

[Jez Nemeth]

Jez, Some of these engines dont like to start by simply turning the engine just over TDC and then kicking........This can depend on the gearbox used as well, but some like the engine tuned over more, and then kick.......that is, if you push the lever at the top of its stroke, to go just over TDC, continue pushing the lever down more.........re set the lever up again, and then kick.........One other large issue as well, if this engine was one of JR then it could have one of his big cams........If its anything like the one in my racer, the duration is massive.......The inlet closes not more than 80 or less degrees before TDC and they have a huge overlap.......this means that part of the intake charge is being pushed out before it gets drawn in........So that could make starting difficult as well........It will come down to some careful but simple settings, but probably just technique to start it every time..........My Rapide has quite big cams in it, and it needs a good firm kick to start every time........If you use a lazy kick on mine you will be there all day trying.........The joys of hotted up engines........All good fun.......Cheers.

Been using and trying that technique you mentioned way back Greg, and that's how I started it both times, bringing it on with a slight throttle increase once it catches. My problem is I think I'm TDC deaf. Like some folx are tone deaf -I have a real hard time working out where compression/top of stroke is half the time -can set it by hand to just over though, bring it back up then jump on it...it's a hell of a workout, up down.
I'll reset carb with a bit more revs again and play with that...unfortunately out tomorrow cutting away rust and welding in new panels on my T3 in a local garage all day (Sat).

Both times it went with a good rotational kick, surprisingly not huge on both occasions, same as a 500 -lazy don't cut it with this one. Jacquline Bickerstaff was super generous with her time one evening at the Glos Rally few years back and went through her bike technically, tip to tail- answered all my questions when I was still putting my bike together. Can't thank her enough for the time spent and sharing fathomless knowledge and advice -Just turned my internal recorder on and listened. Took in all the technicals and advice - above everything she said this phrase resonates - 'They're all different, individual -no two are or behave exactly the same and you only get to know your bike by spending time with it' -'character' is the term I believe that was the first time I'd heard that said, and although heard it many times since, it never fails to raise a wry smile from now knowing through experience what it means.
-so the quest to find the variations of starting technique for when its cold/hot is still on for this particular machine