Kawi2strokes.com Forum

Have been going around in circles trying to get the
bike running good. It’s way better now, I won’t go into details but I now suspect low fuel level.
A while back (round in circles) I set the level to lowest spec I think. But they are viton tipped
needles and half inverted or fully inverted didn’t make any difference.
The bike goes great till power band hits then it feels like one cylinder is momentarily cutting out completely. Quickly on and off. Almost feels like a spark problem.
My question is…..can viton needles differ from traditional ones with actual fuel level?
And could low fuel level cause my symptoms?
Thanks
I am confident my jetting is very good.

Several questions come to mind....
Did you set fuel level or float height? Fuel level is the most accurate way.
If you set float height was it set at float opening?
Set upside down or on side?
It has been said by some that min float height (max fuel level) is best setting.

_________________
Answers are here: http://kawatriple.com/

What engine is it? Is the electrical system stock?

_________________
If it surges, that's normal, upshift.

Coops, yes, fuel level in bowl has the most influence when fuel pick-up and then delivery rate are done.

Most evident at lower RPM.

Higher revs are a crapshoot due to frothing.

Suspecting, like Dale said as above.

cliff

Ok Long story...
Its a h1D that ive had 35years. Doesnt get ridden much, i just work on it Lets just say everything has been done at least twice.
About 7 odd years ago it started fouling one plug and i stopped riding it as interests were racing motorbikes so i just put it away.
Then about 4 years ago i removed the crank because it is a rebuilt one. I wanted it for my race bike. The one in the race bike worked fine but it was unknown.
Now ive lost interest in racing bikes (15 broken bones) So 6 months ago decided to reassemble the D with the crank from race bike. Didnt do a leak test but seals are tight on the crank which was good enough for me. Did a oil pump output check and all three are the same. So figured it was jetting.
Ive been pissing around with jetting and been either side of sweet spot on needles and plugs look great.
Its back to totaly stock bar K&N filter and Ivans jet kit. 105 mains
Then a few weeks ago it all of a sudden got really bad and started missing on all cylinders at higher revs, so i suspected ignition problem.
I have been through everything in electrical system, checked connections, tested all components with meter. replaced the coils. Grounds are all good.
I made the CDIs and rectifier about 15 years ago, they test fine and havent done much work. So i put a new regulator in and that fixed THAT problem.
So now i am at described in first post. The bike goes best it ever has, just random cutting out in power band. Not always though.
Its not a blocked tank cap breather. I spend lots on new plugs

I am slightly stumped and can see only two thing left to do...
Check actual fuel level in the carbs. Previously i just set the float height on low side. (least amount of fuel in bowl)
Or do a real time check on the spark, although i am fairly confident spark is good and its not a easy thing to do while riding the dang thing.
Thanks.

That's what I was getting at... a bad regulator on an H2 type system can cause high speed misfire. Is there any chance the replacement regulator is bad?

_________________
If it surges, that's normal, upshift.

Not really. When i put the new reg on, the bad miss fire, and i mean bad, on all cylinders went away.
I am left with a stuttering on one cylinder kind of thing and sometimes can go through it, sort off.
Totally different symptom..... When its not stuttering, it pulls like a schoolboy.

Im gonna check the fuel level and let yaz know if that fixes it.
Cheers.

Check my post on page 6, it has to deal with fluid vs. float levels.

_________________
1969 H1, 1971 G3SSA, 1974 G5, 1973 H2A, 1975 S3A, 1975 H1F, 1973 Z1, 1988 HD FLTC, Captain America chopper, 2000 Excelsior Henderson, 1965 Bridgestone BS90

Where’s that? Can’t see it on page 6

I just dropped the needles one clip, that cleared up the miss on one cylinder. But has less power so some fine tuning with washers
and maybe different settings for different carbs will work.
As far as fuel level goes it was a little high. I just removed the emulsion tubes and used a cable tie as a dipstick. I personally dont think fuel level is that critical until thing go array. I tested Mikuni Viton ones (installed) also sudco Repop ones near new and my old OEM ones.
Not going to quote numbers but all three were quite different float to body setting to achieve 30mm fuel height. Also the Sudco ones have 2mm plunger travel compared to Mikuni have 1mm travel. While testing, a viton one kept sticking open for some unkown reason. so biffed that and intalled a Sudco. I think that was fine static but suspect vibration..... Leaky
So biffed all repops and install my old OEM ones at 28-29mm fuel level (which equated to 26mm float to body fully inverted) No more seeping bowls.
So moral of the story is. Different manufacturer needles give different results. And possibly, i suspect vibration can cock actual fuel level up.
Cheers.