Hello everyone! New to the forum, i already found some interesting info here but appearantly nothing that suits this problem:
As I said a 1980 Honda CB750ka with VB52A(B) carbs.. I will tell the whole story later but this is summoning up the problem. If i start it up it runs at 2500rpm, after 10 seconds of idling it revs up to about 4-5k. We changed the spark plugs and coils, and tested them and they work. I think the problem is the float height: the floats are non-adjustable and were hanging at the bottom (carb upside down) so I bought a set of new float needles off louis.de, a german website, and put them in. I measured the height and it was too high, at about 20mm instead of 15,5. So i fugered they weren't the right needles. So I went to the official honda dealer and bought 1 new needle for this type of carb. I put it in and this time the height was about 10mm, so too low.
I examined the needles and the previous one is the same as the last one I bought, but still the height isn't right. How can I fix this? I'm still not pretty sure this is the problem.
Non-adjustable, not sure exactly what you're doing to measure 'em. Show us?
Meanwhile, a high idle could be from your idle screw too far in. Could also be your choke isn't releasing, or a vacuum leak, or excess fuel getting in there/not tuned properly.
When did it start? What other work was done when this showed up?
Turbos, Hondas, 4-bangers, what could go wrong?
Shiny: [...] Considering the weather you've had to put up with I'd say you get an Iron Butt award and a Frozen Nipple trophy to go along with it. First time I've ever posted the word nipple... it ends here.