Popping back through the carbs

‘New Premier carbs’…
If they came with #17 pilots it might be part of your issue. Check what’s in there, sounds like you need #19s.
A quick Google search will show you what to look for if you’re unsure.
 
Tin Man said:
When it was starting, it was needing full choke, even on warm days.
Click to expand...

Ok, so with the new Premiers, approximately how many seconds does it take before fuel drips from each tickler (when pressed and held down, not 'pumped' as some owners tend to do which only slows down the rate of filling)?
 
if its got fresh plugs, getting spark and fuel- then it should at least start and run to one degree or another albeit only briefly..

If it doesn't- and for a fact #1 and #2 above are correct- then it can only be timing. ( Assuming mechanically ok).

the old rule if it pops through the pipes too retarded, if through the carb too advanced. I'd look there first.
 
Does it start on ether?
Popping back through the carbs
 
It should start and run even if briefly on a tickle. Either should have the same effect. The Pazon Altair stabilization only comes in off idle and has zero to do with starting. I'm happy with that feature although there are others that say that an overly rich mixture will accomplish the same. But that argument has nothing to do with this problem. It would seem that the spark is arriving at the wrong time. The other issue of not revving past 3500 may also be related. Walk away and start again like you've never seen the machine.
 
I have to ask and with all considerations taken into account...is your degree wheel setting before TDC or maybe things got transposed and the setting is after TDC?
I ask because I've seen it happen too many times to discount
 
acotrel said:
Does it spit back through the carbs a few times when the motor begins to run - or does it actually backfire through the carbs or exhaust, when you try to kickstart it ?
Click to expand...
Will not start. Farts through the carbs when I kick it.
 
JimNH said:
It should start and run even if briefly on a tickle. Either should have the same effect. The Pazon Altair stabilization only comes in off idle and has zero to do with starting. I'm happy with that feature although there are others that say that an overly rich mixture will accomplish the same. But that argument has nothing to do with this problem. It would seem that the spark is arriving at the wrong time. The other issue of not revving past 3500 may also be related. Walk away and start again like you've never seen the machine.
Click to expand...
I can only wish that I had never seen it.
 
Lineslinger said:
I have to ask and with all considerations taken into account...is your degree wheel setting before TDC or maybe things got transposed and the setting is after TDC?
I ask because I've seen it happen too many times to discount
Click to expand...
That's why I took it to a mechanic. I could have screwed up stuff like this, although I generally don't. Butch has been working on Britt bikes since the 70's, and after checking my work, he can't figure it out either.
 
Tin Man said:
That's why I took it to a mechanic. I could have screwed up stuff like this, although I generally don't. Butch has been working on Britt bikes since the 70's, and after checking my work, he can't figure it out either.
Click to expand...
Well then, we all want to solve this riddle!
 
the danger in troubleshooting, is taking a shotgun approach. Not only does it waste time, but it doesn't teach much.

Think about what your 2 main symptoms are: 1) won't start 2) when it tries, it coughs through the carb.

That's your starting information. You have ruled out 2 things: 1) you have spark at the plug & fresh plugs 2) you have fuel at the carb.

If everything else is correct- ie valves set correctly, timing set correctly............ that bike is going to start- I don't care how out of tune the carb is, or anything else- if spark at the right time, fuel- it will start. It might not stay running, or run like crap- but that's another issue and not the current one.

Since you have ruled out 2 of the three reasons........... the only thing left that could be wrong, is timing.
 
I use an AK47 approach to troubleshooting. lol

Nortons are kind of sensitive to inaccurate timing.

This won't help but is a fun example:

Have you ever timed a carbureted V8 180 degrees out cuz you were in a hurry and not paying enough attention to what you are doing? If you have, you know it will backfire up through the carburetor and not start.
 
Tin Man said:
That's why I took it to a mechanic. I could have screwed up stuff like this, although I generally don't. Butch has been working on Britt bikes since the 70's, and after checking my work, he can't figure it out either.
Click to expand...

When I get ambushed by a problem such as yours I reverse course and step by step break down that which I have assembled/created.
Sometimes this can take you to the land of "how the @#$% did I do that!"
There are only so many avenues available for an ignited charge to blow back through your carburetors. It really sounds like your issue is timing
 
Has a different EI been tried? Could be informative of the ultimate problem.
 
The possibility of a weak battery was mentioned in post 10…

As it hasn’t been renewed, the age and condition of the battery must surely be suspect now?
 
Tin Man said:
Will not start. Farts through the carbs when I kick it.
Click to expand...
What does ‘fart’ mean ?? (you might think me pedantic, but I’m not, the more accurate your description of the symptoms, the better help folk will be able to give you).

A big engine like this will always make a noise through the carbs when kicking it over, air being sucked in or pushed out (like a fart), especially with no air filter fitted.

Is it actually firing, or not? Ie does the fart sound different with the ign on / off ?
 
Schwany said:
I use an AK47 approach to troubleshooting. lol

Nortons are kind of sensitive to inaccurate timing.

This won't help but is a fun example:

Have you ever timed a carbureted V8 180 degrees out cuz you were in a hurry and not paying enough attention to what you are doing? If you have, you know it will backfire up through the carburetor and not start.
Click to expand...
True dat, and both plugs fire at once with a wasted spark in one cylinder. Good thought though.
 
Fast Eddie said:
What does ‘fart’ mean ?? (you might think me pedantic, but I’m not, the more accurate your description of the symptoms, the better help folk will be able to give you).

A big engine like this will always make a noise through the carbs when kicking it over, air being sucked in or pushed out (like a fart), especially with no air filter fitted.

Is it actually firing, or not? Ie does the fart sound different with the ign on / off ?
Click to expand...
Yes, it firing, but popping back through the carbs.
 
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