Half-Caf: my '80 cb750f SS cafe project

[Half-Caf]

Hmm, thats good news, Tools. Tips on how to remove the limiter screw caps?

Also, how does one go about blocking the air cut valve?

[TOOLS1]

Drill a very small hole in them, and screw a No#2 wood screw into them, and pull them out. To block the sir cut valve. Cut a rubber plug, and use it to plug the hole in the carb. Then reinstall the air cut valve over it.
TOOLS

[Half-Caf]

K, was on vacation last weekend, but just got back to find my shiny new rotor and regulator/rectifier!
Now only if it wasn't cold and rainy all the time...

Will hopefully be borrowing my buddy's impact and swapping out rotors soon. Stay tuned!

[shinyribs]

I'm tuned!!!

[Half-Caf]

shinyribs wrote

I'm tuned!!!

Good to know someone reads this thing!
(That fish tank is for you, Ribs )

Think I may head out tonight to do a little work on it (bike is in my buddy's garage)

[zombiekillinEMT]

So, I'm having about the same electrical problem with my bike. I'm looking into getting a new rotor. There's no good field test for the regulator/rectifier. Is it just a given to replace it when you replace the rotor?

[Half-Caf]

I know many would say that they can go hand in hand, but I don't think that's necessarily a hard and fast rule... I have read that the rotor shorting out can be hard on the r/r and cause it to short out. However, these parts are generally about $100 a piece, so I'd personally want to be pretty sure it was bad before I replaced it.

There are a couple places on here where people explain how to test the r/r. Some methods require the bike to be running and have a good rotor, but I know there is at least one method where someone tested theirs with the voltage option on their multimeter. Just give the forums a search and see what you can turn up.

[Half-Caf]

By the way, decided to just come home and save the bike work for another day
Pouring rain and 60mph winds -they don't call it the windy city for nothing...

[TOOLS1]

Half-Caf wrote

By the way, decided to just come home and save the bike work for another day
Pouring rain and 60mph winds -they don't call it the windy city for nothing...

That SUCKS!
TOOLS

[shinyribs]

Dont ride in the wind with a dirt bike helmet...my neck still hurts.   Thanks for the fish tank!I dig it! It has been added to the collection

[Half-Caf]

Snuck away for an hour to work on the bike today. Could not get the bolt out of the charging rotor for the life of me -the vice grips slipped off before the thing would budge
Will probably give it another shot tomorrow morning.

On a side note, I did notice that the rotor had shorted out once again. I'm wondering if this is due to the faulty rectifier/ regulator (possibly sending excess voltage back up the line??).
Will remember to take my camera tomorrow so I can get pics.  

Will try my buddy's impact tomorrow to see if that does the trick, but I'm not holding my breath...
Also, I'm afraid to use heat on the bolt because I am sending in the old rotor (as part of the price agreement) and think that a torch would damage the composite-like material on the face.

[Half-Caf]

Just to specify, the bolt I'm having trouble with is the one securing the rotor to the engine, not the removal tool (which is what most people seem to have a hard time with.)

[TOOLS1]

An impact should spin it right out.
TOOLS

[Half-Caf]

Ok, after about 30 minutes of wrenching, impacting, hammering, and spraying the bolt with blaster, my buddy and I finally got the bolt out with the breaker bar from his truck.
The new charging system is in and I have fingers crossed that it will do its job (I'll be monitoring it for the next couple days).



A few things of note:
-I turned the bike on and it began leaking gas, as before. This time I noticed that all 4 carbs were leaking. I thought that maybe I was just an idiot and forgot to tighten the drain screws, but I checked and they were all secured tightly. I tightened the idle screw to see if that helped and the gas stopped leaking and the bike actually began to idle (around 2k) However, I went around the block and the idle was gone and fuel was leaking again.. Wondering if this is not related to the floats being that ALL 4 carbs are leaking!

-The idle is very intermittent. I am always afraid to let off the throttle because most of the time it just dies. Around 2.5k some crazy things happen -the engine seems very unstable as it apparently is deciding to idle or go off the throttle. At one point, I let off the throttle and it was all the way up at 3k! I revved it a bit and then it went way low and almost died.

-There is still a popping around 4k and the rpms drop waaay down when I pull in the clutch to shift. I believe these issues will be taken care of when I clock the carbs.

-Finally, when I first started the bike (just to shift to 5th before removing the rotor) I noticed a streak of something down my left header. I believe it was a mixture of oil and gas coming from that cylinder. Does this point to faulty cylinder or piston gaskets? In that case, I may be looking at an engine rebuild this winter...





Definitely some oil mixed in there.

Even with all the issues, its still good just to be back on the road for a couple days of decent weather.
Looks like I have my work cut out for this winter...

[Half-Caf]

Hmm, after reading this post, it sounds like the seats for my float valves could use a good cleaning. Perhaps all the excess gas partially explains the leak out of that left cylinder...

Wondering if I should go the ultrasonic route this time as it seems I almost did more harm than good last time I attempted to clean my carbs.

[Half-Caf]

Uploaded some pictures to the post above.
I have been riding the bike around quite a bit and it seems to be doing ok as far as the charging system goes. The idle is still a bit crazy, but that is to be expected I guess until I take off the carbs for a good cleaning (want to enjoy the good weather while it's here).

[TOOLS1]

An ultrasonic cleaner would be nice. I just disassemble everything, and use a cutting torch tip cleaner (the one that has little drill bits), and go through every hole.
TOOLS

[Half-Caf]

Had a great day today! After church and lunch with a friend, I decided to go for a ride. I took the twistiest route north that I could find and ended up in Wisconsin. It turned into about a 4 hour ride

The bike stalled out a couple times due to idling issues, but fired right back up. I also still have my gas leak, which resulted in me getting some horrendous mpg's. I'm guessing it was around 5 gallons for somewhere north of 80 miles. But it was well worth it -I'd rather be riding my bike while it's nice than have it apart in a garage.

I took a few pics for you all:







Also, I had a few first on my ride today: first burnout; first screeching stop; first time on the highway; and first time maxxing out my speedometer

In other news, I also picked up an older 1/2 hp compressor to aid in my tinkerings (was only $10). I'm thinking this will help when cleaning up the carbs and maybe laying down some paint as well.  

[Daddyman]

HalfCaf I really like the look of that bike.  Glad ya had some fun with it!

[Piute]

al-right Half-Caf