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need help with jetting.

Posted: Sat Aug 17, 2013 9:12 am
by tclayton9
OK so I've been having a problem with my fizzer. When I blip the throttle it bogs and when I try to haul a&* on her it hesitates a little like it's not getting enough gas. Plus it has a little bit of a rough idle. Yesterday was my third time in the past 3 months checking my carbs. Everything is clean, fresh gas, no restricted fuel flow, and screws are three turns out. But yesterday I realized something. The previous owner had installed a aftermarket exhaust. You can barely tell because its a dull chrome but the mouth of the exhaust is wider. So I was thinking to fix this problem I would install 110 mains. I also wanted to install new pilots but I have no idea where to start. Can someone help me out on what to use and where to purchase them from. I am running the stock airbox.

Re: need help with jetting.

Posted: Thu Aug 22, 2013 12:31 pm
by tclayton9
bump

Re: need help with jetting.

Posted: Thu Aug 22, 2013 7:41 pm
by DonTZ125
Pilots and mains you can get from a Yammy dealer or a Mikuni dealer. Have you checked your airbox and boots, like I suggested?

Re: need help with jetting.

Posted: Thu Aug 22, 2013 8:01 pm
by tclayton9
Today I tore the carbs down checked everything, set screw's to three turns out checked carb boots and intake boots. I made sure everything was air tight. I started it and sprayed starting fluid around the boots and it didn't change in rpms. it no longer runs lean but at a stop sign it idles around 1000 like it wants to shut off and twice in my drive way after sitting for about a minute it did. And when I try to haul a$& its a slight hole in the power band.

Re: need help with jetting.

Posted: Thu Aug 22, 2013 8:05 pm
by DonTZ125
Get the engine warm, then adjust your idle screw so you're sitting around 1200 rpm.

Re: need help with jetting.

Posted: Thu Aug 22, 2013 8:11 pm
by tclayton9
Would that help the hole it the powerband? I also thought that an aftermarket exhaust needs re-jetting.

Re: need help with jetting.

Posted: Thu Aug 22, 2013 8:19 pm
by DonTZ125
Depends on the pipe. Some do, some don't. And trying to pull away from a light from below normal revs is an exercise in futility.

Re: need help with jetting.

Posted: Thu Aug 22, 2013 8:23 pm
by tclayton9
OK I understand. But today after I tweaked with the carbs. It shifted so smooth and nibble. I'll just keep it where its at. I mean it does gets me out of dangerous situations quickly, its not like I'm racing it. My last question......is it normal for the brakes to rub a bit on the rotors.

Re: need help with jetting.

Posted: Tue Feb 23, 2016 12:22 am
by TomJ
tclayton9 wrote:...is it normal for the brakes to rub a bit on the rotors.
Yes. To an extent. Jack it up till the front end's off the ground and spin the wheel. It shouldn't "feel" like it has drag, spin somewhat freely, but you'll hear the pads scraping slightly on the disc. If there's friction you can feel, then something's hanging. Have you flushed the system? DOT4 or 5.1?