Exhaust Valve Issue Concern -- 1979 CBX
Posted: Mon May 06, 2019 9:52 pm
There are so many things this issue might be that I am seeking input on so lets start with the basics.
1979 CBX1000 with a totally rebuilt motor (TIMS CBX) with about 3000 miles on since refreshed.
Airbox Delete running K & N Pod Filters.
OEM Carbs recently redone by Old School Carbs
Bike has been running fantastically the last several month. Fires right up after sitting for a week or more.
I recently perform the cam chain tensioner tighten procedure called out in the OEM Manual. This quieted lots of the rattle down.
Life is good in CBX Land--until this evening. I picked up the CBX out of my storage unit where it has been parked about 7 or 8 days on the battery tender at about 4:30 and rode it up the street to get gas then back home. Parked the bike on its side stand (with the Petcock off) and waited out a nasty Florida rain gusher. 6:01PM, I head out to my patio where the CBX was parked to take my evening therapy ride. Throw my leg over and completely upright the bike, turn on the Petcock, turn the key on and pump the throttle twice, press the starter and I get a god awful sound like the starter slipped a couple gears or some other mechanism protesting and the bike struggles to turn over. Mortified that I just experienced perhaps the dreaded Hydrolock I have heard about around the camp fire late at night I let off the starter button for a few seconds, turn off the key. Took a deep breath and turn the key back on and pressed the starter button again. This time the bike turned over albeit labored and started. But immediately I could tell something was not right. Total pitch change coming out of the exhaust, poor throttle response, and just rough running. Thinking I just needed to work out the cramp--so to speak--I rode out to my parking lot and did a 360 walk around and could see no signs of oil leaks or anything obvious. So what would Burt Munro??? Ride the thing around the block to see if things clear up or get worse. Bike runs terrible at about 65% power. I felt all 6 headers to see if I lost a coil and all six were toasty hot. How the bike is running and sounding to me it feels like I lost an exhaust valve somewhere in the system.
That god awful sound that I wrote about above came from the top of the motor on the left hand side.
Well being unable to channel Burt Munro anymore this evening I am not sure where I should start first..... Compression test starting left to right? Carb inspections?
Trying to remain positive and optimistic here but this CBX project has been a cluster since the day I picked up the bike in Dec 2016.
1979 CBX1000 with a totally rebuilt motor (TIMS CBX) with about 3000 miles on since refreshed.
Airbox Delete running K & N Pod Filters.
OEM Carbs recently redone by Old School Carbs
Bike has been running fantastically the last several month. Fires right up after sitting for a week or more.
I recently perform the cam chain tensioner tighten procedure called out in the OEM Manual. This quieted lots of the rattle down.
Life is good in CBX Land--until this evening. I picked up the CBX out of my storage unit where it has been parked about 7 or 8 days on the battery tender at about 4:30 and rode it up the street to get gas then back home. Parked the bike on its side stand (with the Petcock off) and waited out a nasty Florida rain gusher. 6:01PM, I head out to my patio where the CBX was parked to take my evening therapy ride. Throw my leg over and completely upright the bike, turn on the Petcock, turn the key on and pump the throttle twice, press the starter and I get a god awful sound like the starter slipped a couple gears or some other mechanism protesting and the bike struggles to turn over. Mortified that I just experienced perhaps the dreaded Hydrolock I have heard about around the camp fire late at night I let off the starter button for a few seconds, turn off the key. Took a deep breath and turn the key back on and pressed the starter button again. This time the bike turned over albeit labored and started. But immediately I could tell something was not right. Total pitch change coming out of the exhaust, poor throttle response, and just rough running. Thinking I just needed to work out the cramp--so to speak--I rode out to my parking lot and did a 360 walk around and could see no signs of oil leaks or anything obvious. So what would Burt Munro??? Ride the thing around the block to see if things clear up or get worse. Bike runs terrible at about 65% power. I felt all 6 headers to see if I lost a coil and all six were toasty hot. How the bike is running and sounding to me it feels like I lost an exhaust valve somewhere in the system.
That god awful sound that I wrote about above came from the top of the motor on the left hand side.
Well being unable to channel Burt Munro anymore this evening I am not sure where I should start first..... Compression test starting left to right? Carb inspections?
Trying to remain positive and optimistic here but this CBX project has been a cluster since the day I picked up the bike in Dec 2016.