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Re: Just Got My RVF400 Dyno Tuned

Posted: Tue Nov 19, 2013 10:50 am
by Drunkn Munky
Very likely you have a air leak then

Re: Just Got My RVF400 Dyno Tuned

Posted: Tue Nov 19, 2013 12:29 pm
by Neosophist
wogstaa wrote:The intake is stock too other than me removing the foam on the snout because it was all dry and breaking up, I can't imagine that would make much, if any difference at all. But then, I don't know these bikes very well... yet

They didn't seem concerned about the jet size though, so I'm confident it's all good. The fuel economy will probably take a massive drop though but that doesn't concern me.

I did notice the idle hangs up a bit though when I come to a stop.
Its running lean, usually caused by an air-leak somewhere... most likely knackered carb rubbers / poorly fited carbs / carb clamps or vaccum line / vaccume take off port opened up.

Re: Just Got My RVF400 Dyno Tuned

Posted: Tue Nov 19, 2013 10:26 pm
by wogstaa
I checked all those things before I sent it in. Carb rubbers are new, clamps all look fine. The vacuum line to the tap doesn't have any splits and the vacuum ports were all tight and covered.

I'll double check the vacuum ports though, I'm just suspecting the idle mix might be set a lean, I had it a tiny bit richer than stock before I took it in and it was fine.

Thanks for the advice

Re: Just Got My RVF400 Dyno Tuned

Posted: Tue Nov 19, 2013 11:16 pm
by wogstaa
Just checked for air leaks... Nothing :)
Idle mix might be a bit lean then, or it may have been set a bit high. I'll fiddle with the idle once I take it for a ride and get it warmed up.
Carbs could need balancing too, I guess.

Re: Just Got My RVF400 Dyno Tuned

Posted: Tue Nov 19, 2013 11:17 pm
by Cammo
wogstaa wrote:I'm just suspecting the idle mix might be set a lean, I had it a tiny bit richer than stock before I took it in and it was fine.
Yes, in my experience if the carbs are seated properly then hanging revs is usually pilot screw not set correctly.

Re: Just Got My RVF400 Dyno Tuned

Posted: Wed Nov 20, 2013 5:02 am
by wogstaa
Cammo wrote:
wogstaa wrote:I'm just suspecting the idle mix might be set a lean, I had it a tiny bit richer than stock before I took it in and it was fine.
Yes, in my experience if the carbs are seated properly then hanging revs is usually pilot screw not set correctly.
That, or carbs are way out of balance. But I'd assume it's pilot screws or just a misadjusted idle as they're the only two things they should've touched and there's no air leaks that I could find.

EDIT:
I am running 95 octane fuel if that has anything to do with the jetting, I can never find a definitive answer on whether using higher octane fuel will affect jetting on carbs.

Re: Just Got My RVF400 Dyno Tuned

Posted: Wed Nov 20, 2013 4:52 pm
by Neosophist
wogstaa wrote:
Cammo wrote:
wogstaa wrote:I'm just suspecting the idle mix might be set a lean, I had it a tiny bit richer than stock before I took it in and it was fine.
Yes, in my experience if the carbs are seated properly then hanging revs is usually pilot screw not set correctly.
That, or carbs are way out of balance. But I'd assume it's pilot screws or just a misadjusted idle as they're the only two things they should've touched and there's no air leaks that I could find.

EDIT:
I am running 95 octane fuel if that has anything to do with the jetting, I can never find a definitive answer on whether using higher octane fuel will affect jetting on carbs.
Not at all.

Re: Just Got My RVF400 Dyno Tuned

Posted: Thu Nov 28, 2013 12:25 pm
by wogstaa
I've actually done a bit more riding since the tune, I need to go back and get them to fix the idle mix, it's definitely lean, it sounds like it's low on fuel when I take off with very little throttle, otherwise it runs really nice.

Just Got My RVF400 Dyno Tuned

Posted: Wed Dec 04, 2013 8:32 pm
by rumpoldstilskin
wogstaa wrote:Hey all,

I just got my bike back from RB Racing.

Thought I'd post up the graphs since I'm no expert on these things to see what you all think... It ended up requiring size 125 main jets, to my surprise.
TSR Titanium system is the only mod performance mod.

[url=http://imageshack.us/photo/my-images/12/ym3r.jpg/][img]

Here's mine; despite the table saying 'vfr400' it's definitely an RVF, standard as far as I know with a carbon end can and had a good service

Re: Just Got My RVF400 Dyno Tuned

Posted: Wed Dec 04, 2013 8:35 pm
by rumpoldstilskin
Image