Bike jerking issues CARB?...

[itsRICH]

The cam is an andrews .470 lift AB Grind, no idea what that means, but it was bought from CCI, and rebuilt, and tested then. So i dont think its a cam issue. Im leaning more towards the intermediate jet replacement. For the gear ratio thought, where could i find what the ratio should be? and what would you guys recommend if i go that route? decreasing or increasing the gear ratio? Im hoping it can be fixed with the replacement of the intermediate jett

[Huck]

My hot rod motor will get into what i'd call a cadense or cycling once in while. Pull the clutch rap the throttle and let the clutch back out appling throttle. Is this a new motor & drive? Clutch maybe a little grabby? Ride it around a bit.

[Bigincher]

My hot rod motor will get into what i'd call a cadense or cycling once in while. ....

A lot like the "snatch" that Robbie described. My shovelhead will do it if I let it.

[olpanrider]

The cam is an andrews .470 lift AB Grind, no idea what that means, but it was bought from CCI, and rebuilt, and tested then. So i dont think its a cam issue. Im leaning more towards the intermediate jet replacement. For the gear ratio thought, where could i find what the ratio should be? and what would you guys recommend if i go that route? decreasing or increasing the gear ratio? Im hoping it can be fixed with the replacement of the intermediate jett

read the last post of the first page..

[itsRICH]

new engine and drive, it was the second ride on her, she did it both times, only rode her up and down the street, not titles/registered/insured, so I didn't want to go far, living on a military base and all, ill try the clutch trick, other tests ive done on the clutch it works fine, so we will see, will try that before I adjust the belt/chain tension, it seems like an easier test.

[Motorcyclemike]

ItsRich........I seen that your NOT RUNNING a inter or outer Primary cover.......BE very careful with a set UP like that....I have seen a few guys that got their pants cuff areas in the belt and they
were lucky enuff to NOT have any serious injurys.......even the 3 studs on the clutch can grab a part of your pants cuff and scare the crap out of yah!.....Plus IF the bike is rode on a gravel road....and you get a rock between the belt and pulley areas....... it can PUNCH a HOLE in the belt !

[Panhead Ed]

Sounds like you are experiencing a condition referred to as "snatch". It is commonly caused by lugging an engine at too low an operating range usually in combination with overly high gearing. If it was a carb issue there would likely be spitting back through the filter or backfiring. If the ignition is not retarding at low RPM it will exacerbate the condition. If slipping the clutch smooths it out it is pretty classic "snatch" or "chain snatch", common terms for the same thing.
And the bigger the engine the worse it can be due to the power pulses.
Raise your idle speed, check your timing,and lower your gear ratio.
Robbie

YOU SHOULD START HERE.

[58flh]

it has a BDL 2" open belt, no compensator, the clutch is working properly, check it multiple times, i tunes the carb per the SS instructions, for the first few steps, it was the maiden voyage. Havent gotten to test the main jet yet, in the higher speeds. when i shift into first and let off the clutch it will roll smooth (had it backwards previous post) , and when i give it throttle it starts to jerk more, untill i get to the top of 1st gear. it was timed at the factoroy with the electronic ignition when it was rebuilt. I just got som carb cleaner, so i will be checking for air leaks,could it be an air leak? since it runs fine as the speed increases..seems like it would be consistant if it was, but im not too familiar with air leaks. Also by the way, this is my first bike ever/first time riding one, except for a riders safety course i took. so im a "new" guy. Ive had someone tell me also that it is normal with a larger engine in low speeds, but it doesnt seem normal to me,

You said when you put it in 1st it gets jerky--THEN WHEN YOU Give it the gas SHES is breaking-up badly until its time pull 2nd & keep going.--I think your S&S needs some help!--If it starts easily & don't break-up until you grab first & its JERKIN you around--That's starving for fuel!//Do you have a line long enuff so that you can loop it to just between the barrels & up into the hole on carb.--(use 5/16-I.D line)& fit your filter near the lowspot on the down from the petcock.Another issue Check you float!/I have had few brand-new in the plastic carboard,& 7-out of 10 The floats worked good.You may just have one of those problems also--I mean it sure sounds like a starved fuel issue to me!--Check to make-sure the auto-advance is working properly to.---RICHIE

[itsRICH]

Correct no inner/outer primary, I have a buddy thats gonna cast me guard for the front pulley, on my second ride it caught my pants a little. Its breaking up up until the middle of 1st gear i would say, not sure of the RPM (no tach) and same at the beginng of 2nd gear. The gas tank isnt complety full either, it probly has about 1 1/2 gals in the left tank, right tank is empty still, and my petcock is pretty much in the middle on the outside of hte left tank. I run 5/16 line that runs down inbetween the heads right at the bottom and runs the length of the base of them then shoots up, just before it hits the heads is the filter, then it runs up to the carb. could that be too long? should i shorten it, and make it more direct...gravity takin too much place in there maybe. Once in the middle/higher RPM of first it doesnt jerk, same when i get to the middle of 2nd unless i keept the RPM/speed up

[Bigincher]

How old is the fuel in the tank, how long has it been in there? If it's older than a few months, especially since the tanks are only half full, I would dump it and add fresh gas. Modern gasoline doesn't store well, like it used to before ethanol was added to the blend. And storing with tanks half full makes it worse, more exposure to oxygen. Always store a motorcycle with tanks topped off to the brim, and something like Stabil added.

[itsRICH]

Its pretty fresh about a week, i only have a 1 gal gas tank to fill up, plan on filling them up when its legal to drive to the gas station, which should be here soon. Im running super unleaded, not sure if thats an issue, i think i read in the HD manual to run as leaded fuel as possible, liek regular (87) not sure if that could be adding to my issue

[panhead george]

do you have a vented gas cap?

[itsRICH]

yes, right tanks vented

[PanPal]

fit your filter near the lowspot on the down from the petcock

Curious why?

Working on a shovel with an S&S shorty B. The mixture screw was adjusted almost all the way in to run right. I timed it, found manifold leaks, replaced manifold seals, bubble tested and passed the test. Put a screen filter near the petcock in a vertical position. Now the mixture screw is almost all the way out to run best. Starts first kick, but when idling it stumbles every so often. I want to retard the timing a bit. Out on the mixture screw is richer right? I would have expected to have to lean it out after fixing the manifold leaks. This is why I like to change one thing at a time but I did too much this time!

[itsRICH]

So i googled some more about this jerking issue im havin, and ive found that other people are saying that its pretty normal in the lower rpm range for the bike to "jerk" I havent had the chance to ride it and test your guys opinions, just got the wiring back together the other day. But some guys are saying that its because of the way the bike is at idle since its like " potato------potato-----potato" idling slow like your lugging the engine, again i did increse the idle speed a lil bit, and it helped somewhat, but they say that you just need to work the clutch more when at the lower rpms, and that is why when you increase rpm it smooths out, because the revolutions are more constant "potato-potato-potato" so i will be trying the clutch working in and out "friction zone" of it and see if that makes it a smoother ride in the lower rpm range. what do you guys think about all that?...