• Can't post after logging to the forum for the first time... Try Again - If you can't post in the forum, sign out of both the membership site and the forum and log in again. Make sure your COG membership is active and your browser allow cookies. If you still can't post, contact the COG IT guy at IT@Concours.org.
  • IF YOU GET 404 ERROR: This may be due to using a link in a post from prior to the web migration. Content was brought over from the old forum as is, but the links may be in error. If the link contains "cog-online.org" it is an old link and will not work.

Soft valves on an '86

P

ProudGecko

Training Wheels
I purchased my '86 in June with just under 16,000 miles. I've since put nearly 5,000 trouble free miles on her. I love the bike and I am planning to keep it for a good long time and as such I'm looking for ways to prevent issues down the road. One of the issues I keep reading about are the soft valves on the '86 that are easily deformed. My question is, should I replace the valves soon with the more recent hardened variety before the soft valves cause damage to other components? Or is it safe to wait until the 60-80k mark when the valves will be shot? Thanks! David S 1986 Kawasaki Concours 1973 Honda CB500
 
David Here is how I handled my 86. I purchased with 9k miles on it and the valves worked fine until they could no longer be adjusted. You have a few years of riding (depending on milage per year). I looked on the for sale and found another Cogger who was parting an engine with about 20k on it and bought the head minus the cams (someone else had gotten them). Then contined to ride for 3 more years with the head in a box in the garage. At some point I could not start the bike and one of the adj as all the way. Doing this probably damages the head but.... When I serviced it I also changed the timing chain and did a 5 deg advance on the cam timing. With the dremel tool I cleaned up some of the casting on the exhaust and intakes a bit and ground off some extra welding on the exhaust manifold to get things to line up a bit better. This was fun and I think did give it a bit of better breathing. I also put a new head gasket on and the part that the cam chain tensioner rides on as I had changed to a newer type that had a different shape (this was not really necessary but is suggestted) I have probably forgotten something but that is how I dealt with the soft valve issue. Bike went to about 40k and I rode it about 20 more and traded it for an 01 which I still have. Log of my labor time was about 20 hours for the compleated R&R of the top end. Cost was about $300 incl used head with valves. Towards the end of the original head you need to adj the valves more and more often so when you have to (or it is running bad and hard to start) every 1000 miles or so you are getting close. It will go out of adjustment faster and faster as the problem gets worse you will have pleanty of warning... Paul Gerhardt From da Beautiful Eastern Shore of Maryland COG 1594 www.pgerhardt.blogspot.com
 
Thanks for the info. It sounds like I should be ok for awhile then if I just keep on top of the maintenance. David S 1986 Kawasaki Concours 1973 Honda CB500
 
No knowledge, only what I picked up from the boards, not all 86's had a problem. There are still 86's running around that have had no problems
 
David Here is how I handled my 86. I purchased with 9k miles on it and the valves worked fine until they could no longer be adjusted. You have a few years of riding (depending on milage per year). I looked on the for sale and found another Cogger who was parting an engine with about 20k on it and bought the head minus the cams (someone else had gotten them). Then contined to ride for 3 more years with the head in a box in the garage. At some point I could not start the bike and one of the adj as all the way. Doing this probably damages the head but.... When I serviced it I also changed the timing chain and did a 5 deg advance on the cam timing. With the dremel tool I cleaned up some of the casting on the exhaust and intakes a bit and ground off some extra welding on the exhaust manifold to get things to line up a bit better. This was fun and I think did give it a bit of better breathing. I also put a new head gasket on and the part that the cam chain tensioner rides on as I had changed to a newer type that had a different shape (this was not really necessary but is suggestted) I have probably forgotten something but that is how I dealt with the soft valve issue. Bike went to about 40k and I rode it about 20 more and traded it for an 01 which I still have. Log of my labor time was about 20 hours for the compleated R&R of the top end. Cost was about $300 incl used head with valves. Towards the end of the original head you need to adj the valves more and more often so when you have to (or it is running bad and hard to start) every 1000 miles or so you are getting close. It will go out of adjustment faster and faster as the problem gets worse you will have pleanty of warning... Paul Gerhardt From da Beautiful Eastern Shore of Maryland COG 1594 www.pgerhardt.blogspot.com
 
I think I've found the problem with my 86, judging by what I'm reading here....the spedometer has gone around once and I have no maintenance records and don't have a clue as to what has been done, and what hasn't been, to the innards on this bike....but it is extremely hard to start when cold and I was under the impression that it was a carb problem....but it sounds like I'd better dig into those valves first. Never checked them but I will be. Is there a quick check...here are the symptoms. 1. Reaaly, really hard to start when cold. 2. Hard to keep it running until it is warm. 3. A burp from one cylinder when idling. I've got the time. Should I be looking for a set of new valves, taking off the head, and getting a pro to install, or should I be looking for a new cam, and new timing chain too? By the way, is the odometer maxed at 100K miles? (The bike is on Vancouver Island and I am in Northern Alberta right now.)
 
You must log in or register to reply here.
Top