Not sure if anyone can help me with this, but figured I'd throw it out there. Looking at a bike with a 124" S&S...carb'd that seems to sputter when you accelerate. Starts up great, idles great...but when get above around 1400rpm, the engine acts as though it's not getting enough fuel. If you keep on the throttle, it picks right back up and runs great over around 35mph. The bike had been sitting for almost 6 weeks in California. The carb was taken apart, float was unstuck, all jets were cleared out, fresh gas installed. That helped, but it still does it. Could it be fuel/air mix issue? Maybe an internal issue?

 

was it running well when it was parked ? what carb an s&s e? g? ? california gas turns to laqir laqer laqeer ...crap ...real fast when apart did you soak the jets and needles overnight in carb cleaner? use a pin drill to check all the jets were clear ?is this during acceleration or just slow roll on .. could be the accelerator pump or fuel enrichner which ever you have

 

Not sure which one, I'll find out. Bike ran great before he let it sit. I felt real bad for the guy...he ended up just cleaning out the jets with carb cleaner, he didn't use a pin or wire. It happens at all levels of acceleration, actually stalled on me when it first happened. After the problem persisted, he took the thing apart probably 4 times....got better, but didn't fix it. I'm just hesitsant on buying a bike that may have a pricey problem, but if it's just a carb issue...that I can get over.

 

AAAAHHHHHHH!! so you were looking to buy !! use it as a bargining chip any good indy shop should be able to sort it out a new S&s super g I have seen as cheap as $275 . and they have great support and a good jetting kit ....did you ever actually ride it ?

 

I rode it several times...right after the carb was reassembled! Thing is a monster! Once you get past the flat spot, it accelerates fast and smooth. It pops a little on deceleration, but otherwise runs great. I can post a pic if you want.....I don't know enough about S&S engines to know if the issue may be more than just a carb problem, I had a 3 1/2 hour ride back and didn't want to take a chance on top of it.

 

when in doubt do a compression check .its real quick and easy can be done anywhere ....and a seller should not complain about it .... depending on the cams /compression ratio etc. etc. giving you a psi figure is not as important as the front and rear being as close to even as possible ..it sounds like a carb problem ...if you get past the flat spot and then it goes it sounds like the accelerator pump

 

Really appreciate the help....didn't factor in the pump. Wouldn't a bad pump prevent it from getting fuel under increased acceleration? He's been very cooperative, don't think a compression check is out of the question. He really needs to sell it.

 

Acellerator pump adjustment, pilot jet issue, or as we have seen in the past, the small "O" ring that sits on top of the acellerator pump nozzle, was misplaced upon re-assembly.
Very good carb that can be modified for more power, as well.
Scott

 

I left a yamaha yz 450 sit around with corn gas in it... BIG mistake. Crap was so pervasive that I had to buy a new carb.

Do the comp check and if front and rear are about equal PSI, AND... its a good deal... I would buy it. How does engine sound while riding... any out of the way weird noises?

Frigging gasohol sucks for sure. When the corn dries up... it 'paints' everything... so all jets and orifices would have smaller diameters. Carb cleaner only does so much.... I've used welding tip cleaners with some success.

I'm another that thinks S&S has really decent support.

 

To ans your ques about the accelorator pump affecting the acceleration...it is the acceleration! it squirts an xtra shot of gas into the airstream when you grab a bunch of throttle and like the guy from hillside said the most common prob is that pesky little o ring