Newbie question... sluggish acceleration, popping and more.. OH MY!

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Newbie question... sluggish acceleration, popping and more.. OH MY!

sub1427
Just picked up my new baby, a beautiful 1980 CB750C. Amazing shape. Awesome body, looks so nice.  A problem I noticed on my way back from picking her up was that she was sluggish when accelerating, I have an old 650 that rips compared to my new 750.  I noticed that once the engine is warm and the choke is all the way down its sluggish, if I have the choke 1/4 pulled out she will do wheelies... Since I just got her I put a can of Seafoam in, its smoking a good deal which is good, the last owner said it was sitting for a year but he started it every once and a while...  Its also very very cold now, today it was around 35 degrees riding home... the bike idles well if the choke is out, 1/2, 1/4 or fully in... Anyone have any input or direction to send me in? Oh and one more thing, it has 4 pod filters no airbox, Im assuming the previous owner had it adjusted since it idles and rides with the choke slightly out... I love this bike so far, it has so much more potential im trying to unlock.  Any help would be greatly appreciated! Cheers! Ryan
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Re: Newbie question... sluggish acceleration, popping and more.. OH MY!

Re-run
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I would bet the Previous Owner(PO) did not rejet when putting on the pods. I bet if you went back to the stock filter system(not as cool, i know) it would run much better. Your condition is one caused by running too lean usually and that is what would happen with just putting on pods and not rejetting.
The ride IS the adventure. The destination is just to get gas!
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Re: Newbie question... sluggish acceleration, popping and more.. OH MY!

sub1427
Do you know what size the new jets should be? I don't have the carb information right now I will check that and get back to everyone.... If the carbs are gunked up and I run seafoam and it smokes like a chimney should I just pull the carbs and soak them? Or just rejet them and clean em if necessary?
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Re: Newbie question... sluggish acceleration, popping and more.. OH MY!

Re-run
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I would pull the carbs and clean them. I do not know the jets unfortunately, I do not have a manual for that year. You might also want to fog your cylinders. Use a can of deepcreep(seafoam in spraycan). With bike running, spray a good burst into each cylinder quickly, shutdown and let bike sit for a bit. Start it up and watch the smoke! this cleans out the carbon in the cylinders. If you run the pods, you will want to go up on the mains at least. If you have a 110 size, start with a 115. Every ride is different though.
The ride IS the adventure. The destination is just to get gas!
ZMX
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Re: Newbie question... sluggish acceleration, popping and more.. OH MY!

ZMX
In reply to this post by sub1427
Definitely sounds too lean.  I'd recommend #75 primary (not secondary) main jets instead of the stock #68.  Upgrading secondary (not primary) main jets to 120 or 125 could help, too.