Carb question

Hi folks, I have a 96 bike. I had to open up the carb for the first time to sort a possible float problem (fuel flooding the engine) but in doing so I snapped off one of the float bowl fixing screws, which had rusted in place. I then damaged the carb body trying to extract the broken screw! Long and short is I'm now looking to replace the carb body. First question is, does anyone have a spare body to sell?(it's the left hand side that's broken but I'd take a whole carb). Second question is, do you know if the CBF models used the same carb, that might make the search easier... seen one on eBay that would likely do the job, but worried in case the spec changed in 98.
Cheers.

Unfortunately CBF500 carbs are different due to the different frames. The throttle linkage is on the side rather than the middle, they also have a throttle position sensor.
The jetting is also different, this was meant to be for emission reasons. Although how they worked that out is beyond me,  as every one I had would do less miles to a tank despite having a larger tank

ANDYC wrote:Unfortunately CBF500 carbs are different due to the different frames. The throttle linkage is on the side rather than the middle, they also have a throttle position sensor.
The jetting is also different, this was meant to be for emission reasons. Although how they worked that out is beyond me,  as every one I had would do less miles to a tank despite having a larger tank

Thanks Andy, that's really helpful.

I have a new carb question... anyone had trouble freeing up the pilot screws? Mine are jammed solid and when I tried to free them I damaged the screw head. It's a weird shape, does it need a special tool?

I think everyone has problems with these screws. A combination of very poor and soft materials in an inaccessible place. This adds up to them seizing most of the time. I don't believe that there's a specific tool for them though. 
When I rebuild carbs I always use a little copperslip on the threaded part of the screws which solves the problem.

Thanks Andy, at least I'm not alone! If I can get the buggers out, I'll be sure to grease them up...

did you try to boil (in water of course) all bodyworks of the carbs ?
without sealing parts, springs , membranes etc.

then, before unscrewing, give a hit on the relative screw , a sharp, hard impact, to separate the threads of the two bodies.

I have got them out now, using heat... for me a gentle blowtorch did the trick. Once I knew there was no special tool, I felt more confident. Thanks.

In the world of epoxy glues etc. there are to rebuild the broken part.
With patience and a good hand of course.
To make a thread, pass the oiled screw through the epoxy when it begins to harden.

burudi wrote:In the world of epoxy glues etc. there are to rebuild the broken part.
With patience and a good hand of course.
To make a thread, pass the oiled screw through the epoxy when it begins to harden.

can you please explain to me or show me with a photo where is the pilot screw? is it on the bottom on each side?

It's the cross head screw above the yellow wheel in the picture.

Thank you so much! So, i took my 1996 model to the mechanic. He took apart the carbs, cleaned and balanced them. When i got the bike, he told me I was running rich. Upon starting the bike i noticed high rpm idle (1900-2000). Didnt have time so i left. Next day i tried to adjust it after a ride when the bike was warm. All good so far. Next morning the bike couldnt start cold after multiple attempts. So i upped the idle knob and started right away, but when it gets warm, again the idle speed 1900-2000. Also, the rpm doesnt come down to idle setting instantly, it stalls for a bit. So i want to try to adjust the mixture cause i think its running a little bit lean. What do you think?

I'm no expert but there's a few different things could be causing those symptoms. I suggest searching YouTube, there's loads of great videos there. I like Motorcycle MD, American but working on same Keilin carbs.

what do you mean : upped the idle knob ?!



what was the reason to get the bike to the mechanic ?

panagiotis wrote:what do you mean : upped the idle knob ?!



what was the reason to get the bike to the mechanic ?

I mean I increased the idle rpm. I got the bike with 34k km and now im at 68k. I didnt have any service history from the previous owner. I changed the exhaust with an open dominator pipe, and I thought it was a good idea to take care of the carbs. Yesterday i adjusted the pilot screws. They were at 2 turns. I had quite of an afterfire and the symptoms mentioned above. I adjusted the screws at 2 and 3/4 as i had the most rpm at idle. Quite smoother operation, minimal afterfire, great smooth pull at all rpm range.When  bliping the gas the rpm goes instantly to the idle setting without stalling or going below. Today the bike started cold no problem. So im quite happy.

good news , enjoy !!