MOTOBRICK.COM
TECHNICAL MOTOBRICK WRENCHING In Remembrance of Inge K. => The Motobrick Workshop => Topic started by: Rightsideup on February 22, 2014, 06:00:58 AM
-
Hello all, as above, new to me K75C - my first K after years of airheads. It's only got 19,500 verifiable miles on it.
(http://img.tapatalk.com/d/14/02/14/eva7aza5.jpg)
The problem shows itself as randomly losing all power above 4,000 rpm, there's no pattern I can see to it, sometimes it will only do it for a mile or two, other times for much longer - it's virtually unrideable when it happens. Large throttle openings cause it to completely bog down though it does keep running, using small throttle openings you can coax it up to about 40mph.
So far I've changed fuel hoses, fuel filter, airfilter, spark plugs, replaced the (split) crankcase breather, checked and set the TPS and, just now, measured the pressure at the exit of the fuel rail which shows 37psi but then, it's running fine at the moment.
All the plugs tend to look as though it's running rich and on one journey home when it was running badly it used a tank of fuel in 80 miles! The current tankful seems to be going at a more normal rate.
Any ideas would be most welcome?
-
I have had ignition coils do some strange things like that.
Intermittent problems can be very difficult diagnose.
-
I've not worked on one, but I'd suspect the Air Flow Meter as it can directly affect fuel management/usage/enrichment etc.....
It could be dirty, sticky, corroded connections, you get the idea.
-
I see it's wet where you live. I would check the coils and plug wires for arcing. The partial leakage of ignition power would show up at higher rpm, and higher engine loads.
-
Check all the connections. In fact clean them all and put fresh dielectric grease in them.
A LOT of problems have been solved this way. I had similar issues and it turned out to be bad connection On the ECM.
-
Just to close off the thread and in case anyone else has a similar problem...
Thanks to all for advice, went through every electrical connector and switch on the bike, cleaned contacts and added grease. Put everything back together and noticed that the multipin connector to the FI module was not clicking in to the little metal clip at the back - unscrewed the clip and bent it a bit, clicks in properly now and the bike runs beautifully!