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Is this normal???

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Baz

Baz

Yoda
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It's been a while (2 months) since she started last, and I've never started her in the cold. It was 28*.
The first 51 seconds of this vid....
https://www.youtube.com/watch?v=2xKdeX_Ftss
....is what she sounded like when first started.
From 52 seconds on, after she'd been idling about 5 mins, she sounds better?
Anyway, in her tank is a 1/4 of 93oct with a blob of sta-bil.

My question may elude to the next problem, possibly associated, I don't know.
When I took her around the block, the gas pedal felt VERY heavy, the pressure applied to the pedal was not proportionate to 'go'. There are new throttle return springs on the heatshield/carb, could this be the pressure I'm feeling? Throttle cable too tight?
As y'all know, it's my first time.
 
Sounds great, needs a bit of a drive to get it up to operating temp then a small bit of carb work, but great.

Wish Miss Agatha sounded like that.
 
How's the timing?
 
Bang on @ 7*
Spent an hour getting that spot on. Vac pointing to around cyl 3 & 4, a little further aft than usual. Carbs were another hour and sounded perfect.
Valve clearences good, plugs, points, rotor, condenser, dizzy cap and wires all new; gapped right and happy.
I just don't remember LBC years ago sounding like this when cold, just something, off about it.
 
Did the sound change when you installed the air cleaners?
 
They're not back on yet, the sound/idle changed after I, 'ahem' gave it a little extra gas when it was warmer.
Still shouldn't barf out the carbs thought right?
 
I don't think so, that's why I asked about the timing...maybe a combination of too rich & timing???
 
If I had to guess...which is all I can do.
I'd say the back carb is a little lean and the timing may be off. When was the last time the plugs/wires/etc were changed.
 
I'm wondering if there may be a little crude in the bowls? A little choke on start-up would probably help during warm-up too! Barfing out of the carbs could be a symptom of valve clearance adjustment issues, or as Tony said, timing! You said 7*, whereas my books say 9*. You might try a tad more advance. Other things to check for the intermittent "barfing" are loose ignition leads, loose battery terminals, loose engine ground strap, dirty, fouled or incorrectly gapped plugs, and pitted points.

After re-reading your post, you covered most of the above but I would check for loose leads at ground, battery, dizzy and coil! and crud in the bowls! The "heavy pedal" feel could also be a weak ignition spark from something loose or poorly grounded! Another possibility I just thought of was the setting of the fuel float. If it is too low, that will also give uneven running and lack of power, as will a leaky intake manifold gasket or cracked manifold!
 
I did clean the bowls (they did have some floaters), and put new gaskets on them. Valve clearance are good.
I used a voltmeter for the timing, so I will recheck any grounds or loose wires.
Before I was called in from the garage, I did have her going again and only had time to check this....
I put the synchronizer on the carbs, and that red ball shot up, on both, whereas before it was right in the center.
No manifold leaks with a shot of carb cleaner.

Back to tinkering.....

Seems timing has been mentioned more than once, I will recheck that also. I use my on-line bible for such degrees Mike, hence the 7*.

After 5 minutes or so, it didn't barf, and it sounded good, just the first 5, each time.
 
Which carb did you set first? Always do the one to which gas goes first.
 
Wait? it only runs poorly when using the choke? Are the jets dropping the same amount on each carb when the choke is pulled?
 
Set front first and did it by the book, handbook, SU book.
Got the jet centered and felt good that they were set, and synched.
PS Are HS4's theoretically different, except wider?
 
Baz, may I suggest that you have a very small air leak in the intake side somewhere. As the engine heats up it seals it off and smooths right out.

It's all I can think of but might be worth checking.
 
Think Trevor has something.
That break in the vid at 51 seconds is where the choke goes in, after that, just like this evening, she flattened out nicely.
What are you thinking?
 
I'm not ashamed to admit this, as I suppose (hope) we've all made mistakes that make you go 'DOH!'.
Next time I adjust the carbs and timing, I won't do it with the choke 1/3 out.
I'll start over tomorrow when it's light and warmer.
Thanks all for everyones time, Sorry!

~gets his coat~
 
Hey, been there done that...right now I've got one that I can't get in time - no matter what I do...& I know how to do it...today I pulled it back in the garage & threw the car cover back over it & walked away.
 
Yeah, the time to try for leaks with the carb cleaner is while it is cold and barfing, then You might notice an improvement in the way it is running. I'm thinking leak, because if it improves as it warms up, heat expansion might be taking care of a spot that leaks while cold! If the bowls had floaters, you may have some contamination in the jets. Opening and closing the choke while revving a bit can sometimes clear a little dirt out of there!
 
ur pedal may be stiff from the lub freezing up in ur cable....it should clear up after it warms up if so....z
 
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