Rvf400 NC35 Idling at 3k RPM (Carb issue?)

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lay0032
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Rvf400 NC35 Idling at 3k RPM (Carb issue?)

Post by lay0032 » Fri Oct 20, 2017 12:54 am

Hey guys, I have recently purchased a RVF400 as a project. I have not had any issues until recently, hence why I have resorted to ask for help.

So my dilemma is that I have cleaned the carbs and after adjusting the float heights to 12.5mm using a Vernier, I slapped the carbs back on the bike with new boots. This is the first time that I have started the bike, so it started with a bit of choke but the issue is that it stays at 3k idle even with the idle screw screwed all the way down. It's able to rev all the way smoothly. I have also got vacuum gauges connected to see if they’re out of sync, which they are spot on.

In addition the pilot screws are all set to 1 5/8 and there are larger main and slow jets. Will have to pull the carbs off to double check what the jet sizes were.

I look forward to find out where I have gone wrong.

Neosophist
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Re: Rvf400 NC35 Idling at 3k RPM (Carb issue?)

Post by Neosophist » Fri Oct 20, 2017 11:18 pm

jet sizes shouldnt have too much if any effect on the idle.

Are the throttle butterflies closing properly and not getting jammed up?

Is the choke fully releasing off the bike?

are the air-screws properly set?
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...

blknoel
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Re: Rvf400 NC35 Idling at 3k RPM (Carb issue?)

Post by blknoel » Sat Oct 21, 2017 7:57 am

I think the biggest impact on idle is, well, the pilot jet (or slow jet as you say). I would go back to stock #35 idle jet. Unless you race there's little reason to have a bigger pilot jet.

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Re: Rvf400 NC35 Idling at 3k RPM (Carb issue?)

Post by Neosophist » Tue Oct 24, 2017 12:51 am

ah just noticed that you changed the pilot jets too.. you shouldnt really change them in the majority of circumstances
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...


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