My 92 cb750sc street tracker build, in need of help!

bombayblack

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So, I took a completely unmolested cb750sc (had the original manual and tool pouch under the seat) and started off with some basics. It's nowhere near done yet, and I'll get to that later.
-Stuck on a cg125 gas tank, that required fabricating new posts for the tank rubbers and some relocating / bending of the rear mount tab of the tank.
-Emgo black cone exhaust on stock pipes
-Emgo black riser bars
-new Avons, wider in the front
-ebay brat/cafe seat, the one that looks like the old tr6 seat
-DCC speedo, tach delete
-dynojet stage 3 jet kit, used only 2 shims. Came with 3.
-Emgo pod filters
-other cosmetic stuff that doesn't make it go fast

So, besides redoing the electronics and fabbing a tail section, I have a carb question...
When the bike was stock, i could roll hard on the throttle at the bottom of first and have enough umph to pick up the front end. That was stock pipes, all baffled up and stock airbox. Those are not going back on.

The bike after exhaust/intake/jet mods runs great, only light sputter after coming off of WOT, and still haven't pushed the bike to it's limits. Pushed it up above 115mph and it still felt like there was room to go. i want that lower end power back. My thoughts are that after adding the cg125 tank, which does not have the vacuum petcock (yhe one with the accelerator pump-looking part on it) and plugging the #2 carb vacuum port, that may be killing the initial pop on the throttle. I've been told that it shouldn't affect it, but I thought I'd ask before I go in and start re-jetting again. Thank you so much for any insight you have to offer!
 

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it looks like you have crappy pods taht might be blocking teh sensor port slowing the slide lift

have peek at this and see if i am right

http://cx500forum.com/forum/cx-customization-mods-forum/14114-pods-plug-atmospheric-ports-2.html
 
Those carbs probably have accelerator pump on number 2 carb plus air cut valves on all 4 carbs.
The CG tank doesn't have stock petrol tap?
If so, that may be a major issue as it was designed for a bike doing 150mpg not 150 mph.
It wouldn't have an effect at low engine speeds though as your not using fuel fast enough
I also very much doubt it's running as well as you think, Honda design the intake system to be difficult to modify plus provide best performance with stock airbox. Changing exhaust system is usually OK but fitting K&N, Uni's or cheap pods requires a lot of modification.
I haven't been inside one of them since mid-80's so can't remember specifics
I'll have to contact my brother and see if he still has his, it's a nice motor but needs frequent oil changes with correct oil or the crank fails (and the hydraulic tappets get noisy)
And, put something on the back end, removing everything like that just proves your a noob plus looks stupid
 
It's your pods, as cool as they look, they don't work as well as the stock air box that had hundreds of thousands put into R&D and testing... the air box is designed around delivering the most out of the motor in all aspects...

and I agree with pj, get a fender in the back to keep the bike looking clean, unless you don't actually plan on riding it much


Sent from my iPhone using DO THE TON
 
cxman said:
it looks like you have crappy pods taht might be blocking teh sensor port slowing the slide lift

have peek at this and see if i am right

http://cx500forum.com/forum/cx-customization-mods-forum/14114-pods-plug-atmospheric-ports-2.html
definitelygonna try that. Thamks man! The thread you sent me seemed that everyone saw an instant improvement.
 
crazypj said:
Those carbs probably have accelerator pump on number 2 carb plus air cut valves on all 4 carbs.
The CG tank doesn't have stock petrol tap?
If so, that may be a major issue as it was designed for a bike doing 150mpg not 150 mph.
It wouldn't have an effect at low engine speeds though as your not using fuel fast enough
I also very much doubt it's running as well as you think, Honda design the intake system to be difficult to modify plus provide best performance with stock airbox. Changing exhaust system is usually OK but fitting K&N, Uni's or cheap pods requires a lot of modification.
I haven't been inside one of them since mid-80's so can't remember specifics
I'll have to contact my brother and see if he still has his, it's a nice motor but needs frequent oil changes with correct oil or the crank fails (and the hydraulic tappets get noisy)
And, put something on the back end, removing everything like that just proves your a noob plus looks stupid

Thank you for the mechanical advice, but your opinion as far as the appearance of my bike was unwarranted. i did say it's not done, so your slant claim that I'm a noob and it looks stupid... Was pretty stupid. But again, O appreciate the wisdom.
 
dakine_surf said:
It's your pods, as cool as they look, they don't work as well as the stock air box that had hundreds of thousands put into R&D and testing... the air box is designed around delivering the most out of the motor in all aspects...

and I agree with pj, get a fender in the back to keep the bike looking clean, unless you don't actually plan on riding it much


Sent from my iPhone using DO THE TON
well, these pods in particular don't look very good. I plan on getting new ones for sure. I'm aware that the easiest route would be to re-introduce the stock airbox, bit there are Nighthawks that run fantastic with pods I'm sure. Just trying to find my way! The bike is going to end up having a subfender, as well as a tail section to give it more of a tracker-y flare rather than an ebay special. i agree, it'll tie things up nicely. Thanks!
 
Nice, I always wanted thought these would make a sweet tracker... better pods might help but in reality what the carbs need are tuned ports, otherwise it will pretty much always rob power.


Sent from my iPhone using DO THE TON
 
cxman said:
i closed mine in with some expanded mesh
sidepanel3-X2.jpg


sidepanel2-XL.jpg


it looked to open

20170404_163222-XL.jpg
looks good man. Yeah, i plan on shaping up a tracker-style tail that will have shortened number-plate kinda bits. Not as long though, just enough to take up some of that empty room.
 
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