'81 CB750k Tracker - Build #3

Some more progress, I think its almost time for a trip to the DMV. I am currently waiting on some small parts (ignition, speedo, signals, filters), but the hard work is just about done. The wiring is pretty much buttoned up, and the carbs are fitted with new GS1000 boots. Also my tank is back with a fresh coat of Porsche forest-green metallic, and it looks great in person.









I did take a break to go for a little spin on this '72 CL I built for a buddy last year. After sitting all winter she fired up first kick.

 
Chicagomike said:
How are those pods working out with the cv carbs

Sent from my SAMSUNG-SGH-I747 using Tapatalk 2
Click to expand...

I'm still waiting for the pods. These are gsxr bst36ss carbs. Still cv, but much more pod friendly.
 
dear lord that green is great. Do you mind sharing the paint code? That is very close to my stock KZ tank. As I want to re-paint mine that nice metallic green plus red and gold pin striping in the stock layout.
 
Out for some tuning.
agysurem.jpg
 
After a dozen or so test rides and carb adjustments I got the bike running acceptable with the pods. But, it still had some bogging and flat spots through the rpm range. Also idle was rough at best. I can see how people can be happy running this carb/pod combo, but I don't know if I'm sold. I don't want to build bikes that look good, but don't work. So I had an idea last night at 11:00 and got to work.
















And a little Instagram video.

http://instagram.com/p/oEN2vzp_26/
 
Idle improved, quick throttle response improved, and on the bench it's much smoother thru the rpm range. Now I just need the rain to stop to go for a ride...
 
pipe needs more length as well
all you are doing with that airbox and pods is killing horsepower
nice fab work though
 
Yep, real nice fab work but I agree with xb, those pods are going to be the main problem with that airbox design. An airbox INSTEAD of pods is a good idea but an airbox AND pods, not so much. The cheap ones have an inner lip that ruins the airflow anyways.
 
they are just plain restrictive and the box makes it even worse
put the stock airbox on it be happy and ride
or the biggest, fattest uni's or k&n's you can fit
chicks don't care what your airbox looks like
 
canyoncarver said:
Yep, real nice fab work but I agree with xb, those pods are going to be the main problem with that airbox design. An airbox INSTEAD of pods is a good idea but an airbox AND pods, not so much. The cheap ones have an inner lip that ruins the airflow anyways.
Click to expand...
xb33bsa said:
pipe needs more length as well
all you are doing with that airbox and pods is killing horsepower
nice fab work though
Click to expand...
xb33bsa said:
they are just plain restrictive and the box makes it even worse
put the stock airbox on it be happy and ride
or the biggest, fattest uni's or k&n's you can fit
chicks don't care what your airbox looks like
Click to expand...


Sorry guys, but I disagree with your theories. As far as the exhaust length, the tubing is the same as stock. The mufflers are shorter, but I don't think enough to make a huge difference.

The problem with pod filters and cv carbs is the lack of sufficient vacuum to lift the slides, and unstable airflow. The pods are not "just plain restrictive", they are the opposite. These cheap pods are less restrictive than the k&n's. By adding the air box with small passages, it allows the carbs to create a vacuum inside the box much like the stock set up. As far as "airbox instead of pods" I could eliminate the pods and add a filter element, but I had the pods siting here. I am only using the pods as filters.

I guess if I wanted to take the easy route I could just run a stock air box, but this is a custom build not a restoration.

Only some ride time will tell, thanks for the input tho. Maybe I'm wrong, but at least I'm trying new things.
 
ncologerojr said:
These cheap pods are less restrictive than the k&n's.
Click to expand...


This statement above is where you might want to double check your homework. Otherwise, hell yes, I dig what you are doing.
 
you are a great fabricator but you don't know fuck all about engine breathing ::)
the "lack of sufficient vacuum" statement really brings the stupid
the restriction of the small pods is a lot to do with the air being broken up into little streams and being too turbulant to soon before the carbs
if your lashup was better the japs would have done it stock think about it
think how the stock airbox has presicely shaped tubes running into a still air large volume box
the air needs to have a place to settle down and be smooth before it jams into the carb
all o that stock airbox design is after much power dyno testing
 
xb33bsa said:
you are a great fabricator but you don't know fuck all about engine breathing ::)
the "lack of sufficient vacuum" statement really brings the stupid
the restriction of the small pods is a lot to do with the air being broken up into little streams and being too turbulant to soon before the carbs
if your lashup was better the japs would have done it stock think about it
think how the stock airbox has presicely shaped tubes running into a still air large volume box
the air needs to have a place to settle down and be smooth before it jams into the carb
all o that stock airbox design is after much power dyno testing
Click to expand...

No one is questioning that the stock air box is the best for power, but some of us make compromises for appearance as well. I'm just looking for the best middle ground. I'm obviously not building a bike for the dyno here. If it doesn't work I'll scrap it. It cost me a few hours and some argon.
I've read all the pod threads as well. The bottom line is, do what makes you happy. I appreciate your input, but don't jump on my thread to be a dick about it. I said "maybe I'm wrong". Saying things like "really brings the stupid" makes you a dick, sorry.

I'm going to keep having fun trying new things.
 
xb may have come across a little harsh but his heart is in the right place. Some here have a hard time with settling for looks over performance.
 
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