Hi guys I have a honda Cb400 Project big one, the previous owner molested the wiring at the front to fit a digital speedo.
The bike now has the dreaded 5500RPM bubble. The weird thing is I've done the mod at the speedo end and the mod at the CDI end it seems better but still runs like crap in my opinion. It revs up to a certain point then it doesn't want to go.
Bike definitely runs better at lower RPM it is running a little Rich I Think. Bike feels like it builds heat up very fast.

Please Im desperate!!

hey guys don't think anyone cares but it was the carbs I still have some issues, boiled carbs in water and dish soap worked a charm bike works perfect except for a little hesitation at the very top of the rev range if someone could offer advice I would really appreciate it.

Had a similar problem with a VFR750ft that came in as an import from Canada it stood for several years until my son obtained it only 3000 miles from new , we started to get it ready for the road cleaned the carbs of jellied stale fuel and it started but would not go past 5500 revs we found out that there are minute airways/jets that cannot be cleaned any other way, until they were removed again and placed in a large sonic cleaner .
That did the trick.