my "new" 81 cb750f

[chrwilkins30]

Got a new problem that just started 20mins ago. Excessive amounts of fuel are coming out of the tiny tube on the bowl. It only leaking from #1 carb. Its only when I shut the fuel off it stop. I'll run the bike with the peacock off and it seems to run for a long time before dieing. Like 15mins at 5000. Once it dies with the fuel off, I turn the fuel back on and in 1 sec its leaking a steady stream of fuel again. What the hells the problem. I only have 150 since back on the road and now more problems.


It also runs like shit with the fuel in the on position. You think maybe the overflow tube broke on the bowl.

[shinyribs]

Sounds like it's flooding (running bad) from too much fuel in the bowl ( running out of the overflow tube). Could be a bad float is sinking or just debris in the needle. More than likely its a piece of trash in the needle. Maybe some Seafoam,or just miles, will flush it out. Or you may need to pull that one bowl off and clean that needle and seat

[chrwilkins30]

Well, that actually fixed it. I ordered a rebuild kit off ebay because 2 out of the 4 carb bowl gaskets are leaking. Not badly put enough to leave a yellow stain around the bowl seal. They are cracked and I'm surprised they are even still holding together.

Thanks shiny.

[shinyribs]

You sound surprised! Of course that fixed it!lol.  Glad it worked for you. Now go wear it out...

[chrwilkins30]

I guess being new to motorcycles I would have ever thought something so simple would be a problem. Haha

[chrwilkins30]

Bikes been running good. Haven't been able to ride as much as I want, but I have been riding. Went for a little 20mi ride to day and noticed after 5 or so miles that the clutch feels wierd. It started getting harder to get into neutral, and when I'm at a light and am about to take off, hold the clutch in, shift into 1st , the Rpm drops down to 600 and it acts like I'm releasing the clutch even though I'm not. What could be the issue??

[shinyribs]

Sorry Chris,I see we left you hanging for a few days. I'm not sure about the DIHC bukes,but that sounds pretty typical for what I'm used to on my SOHC. The clutch drag on the SOHC's is quite noticable,but typical. My GUESS would be,since you have a new clutch,with thicker plates than before,maybe the drag is just more apparent then it used to be. It would sense since it gets worse with heat. Expansion of the plates. Possibly the clutch could be adjusted a little bit too tight? Do you have plenty of free play in your clutch lever?

[Hellbilly429]

I would adjust the cable too, am sure you will have to mess with it at least a few times while the clutch breaks in.

What weight oil are you running btw? Maybe the oil is thinning out too much as the bike warms up?

[chrwilkins30]

5w-40 rotella synthetic.  I have adjusted the damn clutch 30 times just to get it usable. Its a pain to get that thing perfect.

[Hellbilly429]

Wow, that is a lot of adjustment, lol. Read up on this thread, sounds like some wet clutches are picky about synthetic oil. I am a huge fan of synthetic oil, so I am in no way saying that this is the problem or that I wouldn't recommend using it, but might be a good read for you.

http://www.zxforums.com/forums/oil-lubrication/13675-clearing-up-myths-synthetic-oil-wet-clutches.html

[chrwilkins30]

Dang clutch cable broke. Luckily I was just in a alley. Got one on order from bike bandit.

[shinyribs]

That sux  I know when we used to ride dirtbikes up in the mountains we all had extra parts ziptied to the bike. Every dirtbike I ever owned has a clutch cable and spare levers ziptied to the frame. They like to snap off when you fall down lol.

[chrwilkins30]

Yep. My kx125 clutch lever is bent to shit for falling on a landing. the brake cable is broke at the lever for the same reason.

[chrwilkins30]

got My cable in last week. Today I finally rebuilt the carbs and everything is working good except the #1 carb boot has a small tear in it. So the idle is slightly fluctuating, but nothing unbearable. 2 carb bowl gaskets where torn and all of the bowl drain screw gaskets where f'd up and everything was yellowed. Its nice not now that under the carbs and the spocket cover is not looking like shit.

Anyways, I've been going on longer trips lately and my hand get cramped on these long interstates. Has anyone tried the Go Cruise Throttle Control. I just want to know if they are long enough to reach the brake lever and if they will work on a stock bar and gribs.

[shinyribs]

I'm not familiar with that throttle control,but Crampbuster's work good and they're cheap. $6 at the local bike shop. One size fits all.

[chrwilkins30]

That would work, but I want to be able to completely remove my hand if needed.

[chrwilkins30]

been riding a little but not much because it keeps raining. But I went for a little ride today and when I got home I went inside with my bike running to get the keys for the garage and when I came out there what smoke by the shifter, look down and its leaking gas. It was coming from the #2 carbs overflow tube again like before. So I spent 3 hours removing that bowl and cleaning it out without removing all the carbs. And lets just say its a but PITA. I didnt want to pull the carbs because 2 front carb holder are cracked and 1 rear airbox boot is cracked. So I have came to the conclusion that I want to install pod filters. Oviously not onto these carbs because Im not dealing with all the issues of theses carbs with pods. So I came across these CR racing carbs that people are using. Which model of these go on these bikes. I will get them over winter when the bikes getting redesigned.

Thanks for any help.

[chrwilkins30]

Would these work??

http://www.dimecitycycles.com/vintage-cafe-racer-caferacer-bobber-brat-chopper-custom-motorcycle-carburetors-keihin-cr29-cb750-sidedraft-racing-carburetor-016-3026.html

[shinyribs]

I've heard alot of good things about the CR29's on other forums. It was all on SOHC's ,though. If they will fit up to spouts on your head I don't see why they wouldn't work.

[chrwilkins30]

I emailed them today and got a reply saying that they would be a great choice for my bike and would work perfectly on my basically stock set up. They also went on to say it would give a bump in performance.

Do you know if these are set up to be installed, as in no tuning required, Just get on the bike and go?