TOPIC:

I seem to have a problem with my twin not wanting to rev over 5000 RPMs ,Bike idles good to fair since I have not been around a twin in awhile ? , What I have done is ,,, New plugs and lubed the advancer .Replaced Wires and coil with known good ones ( Used ) . , What I plan on doing ,, Check petcock for good flow and float levels ,, By the way What would be float levels as my manual wont be here till later on in the week .. I hope .. Any good input welcome ,, Thanks Shoeman

From the manual:

Service fuel level: 3mm + or - 1mm

Float height: 18.6mm from the mating surface of the carb to the step on the float.

Air filter in good shape?
Exhaust not plugged?

How do the new plugs look after running?

Whenever I see posts like this I wonder, "What happens at x000rpm?"

5000 is a little odd, because your already fully advanced, so it's likely not the advancer. You're already on the main jet of the carbs lower than that, too. You didn't mention "bogging" or anything like that. I kinda wonder if there's some major intake or exhaust restriction? Or are you jetted correctly for your intake/exhaust?

By the way, I can't remember at the moment - isn't 5000rpm something like 70-75mph?

At 5000 it starts to break up .. The plugs look white in the center sooty around Hmmm Right ? I have not changed the jetting from what I got it fom But have thought of it ,, early 80's bikes are always lean ,, It also wants to pop out the exhaust on quick decell ,, I know lean pilot ,, Hmmm I wont rule out bad gas either ,, The gas is these days Kinda scratching my head on this one , Thanks for the info Steell ,,

Shoe48 wrote:

...The plugs look white in the center sooty around...

Remember, my advice is probably complete crap. That having been said, here's what I would do: Since your plugs are exhibiting signs of both rich *and* lean, you need to find out why. So, first adjust the floats to factory spec. Then, follow the "plug chop" procedure commonly mentioned in this forum. You need to see what your plugs look like from only piolot use, and then only main jet use. Then you'll know what to adjust.


EDIT: You know what, come to think of it, that's how my plugs looked before I did the "coil mod". Not saying you need to, just relaying an anecdote...

Post edited by: Biquetoast, at: 2006/09/20 08:27

I hope to get back on it today . I have a few things that need done in front of it , Funny I was thinking the same about the coil , I will go over my hook ups on it and maybe go get a relay and try that .. I will post to let all know what happened ,, Thanks for your input , Shoe

Shoe48, Is the factory airbox still on the bike? What pipes?

Yes it all stock so far .. Runs Great under 5000 ,, ?? I am about to head out to the garage

I went out tonight to look over the bike , What I found was the small harness that goes between the coil and main harness had a bad conection .. I soldier it up straight ,, I also found the the vaccumn line to the petcock was pinched , as this all helped it is not the problem .. I wanted to do this in stages so I know exactly what the problem is , As I rode tonight it ran very strong up to the 5000 mark ,, You can feel the bike start to break up then as you roll the throttle back it will smooth out ,, The Carbs and petcock are next ,,I will be looking for float levels but also Drop along with the making sure the fuel valve is working ,, It flows with a Vaccumn hand pump installed ,, But should it hold that vaccumn ?? This leaks off ..anyway that is where I am at as of tonight ,, Shoeman