The CX screams from idle to 4900rpm and hits a wall. Sometimes I can baby her past it, but not often. If I get by it she screams on up to 9800 and does it again.
I have determined that it is 100% rpm relative and not throttle position.
That's all I've determined.
this is a 1980 CX500.
It's getting old going to 5000rpm in second, hitting first to get past the wall and have to continue on like I'm running away from the cops.
Worn contacts on the ignition rotor/setup????
would that be a frequency thing?
Dunno, but it could cause those conditions...check your ignition rotor
wait...this is a cdi bike...I don't think it has points...
Hmmmm......yup the '80 cx500 is cdi :icon_confused: :icon_confused: :icon_confused: could be something in the valve train loose????????
not sure what could be loose that would cause the 4900/9800 thing...
Check your grounds. Maybe even add a ground wire to the block somewhere. I dealt with a similar issue (RPM specific misfire) in a Datsun engine. It turned out to be an engine resonant frequency that was causing an ignition problem. More direct ground wires solved it. :dunno_white:
first suggestion I've heard that made sense. The bike does only have onoeground...from the battery to the frame. I'll have a few more.
and to think im lookning at a cx now, . might have to reconsider
remember...I found my CX under four years of garbage and bird shaZam! being held together by bits of bailing wire, duct tape, nylon chord, and silicone caulk. I had to boil the carbs in parts cleaner for a grand total of 8 hours just to clear the crystallized fuel and I had to take the clutch cover off and beat the clutch pack with a 10lb sledge to make it let go.
http://photoartclub.net/gl1000/DSC02038.JPG
From ^that^ to:
(http://photoartclub.net/cx500/cx500done2.JPG)
Now it's a keeper. Odds are if the one you're looking at already runs, it's a keeper.
runs damn well :icon_twisted: :icon_twisted: :icon_twisted:
Then it's a keeper. What year is it?
(I also sell and exhaust and 310mm big brake kit for them...shameless plug)
added aground from the terminal to the main ground, cdi box, rear inspection cover, and clutch cover. Didn't make the problem go away but damn is it an improvement. Rolling on ini third, fourth, and fifth from a stop is sooooooo smooth. There's still a hiccup in first. Second is iffy.
I'm glad it helped. What also helped my Datsun engine was to clean the backside of the ignition module (it's metal and acts as a heatsink and ground) and the area it mounts to. I'm not sure how that relates to your CX, but maybe you can think of something.
One of my Datsun guru friends always says of engine problems, "if you think it's fuel, it's electrical; if you think it's electrical, it's almost always fuel." Danged if he isn't right a LOT.