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Restoring a 1986, very slowly.

D

Dempster

Big Wheel
It is a long story, but about six years ago, I ended up with a trashed, but almost running 1986 Concours in my garage, and like a fool I paid a guy 400 bucks for it....and it sat there for a year. Eventually, I hauled it over to another friend, who is prtty good with bikes, and he got it running....and when it is warmed up and running, it runs nice....with a bit of a burp from one cylinder at an idle....but that goes away when I put it under load. So it became a hobby, bidding and buying replacement parts off of Ebay, piece by piece... Now its almost roadworthy, and although I'm a little fearful of the road because its been a lot of years since I've ridden in traffic and Spring is the plan.....it looks good too....but from a cold start, it is terribly hard to get and keep going until it is warmed up, unless its really warm....like at 3 in the afternoon on the hottest day of the summer. The carbs look gummy and I ran some cleaner through, but it is still impossible to start on a cold wet day in winter....(the bike is located on Vancouver Island and I work up in Northern Alberta so haven't had much time in the past year to investigate this) I'm thinking of buying a set of good used carbs and taking it to a mechanic for tuning once I've got them on.....any other ideas? Is it possible for a layman to tune them or do I need instruments? The spark is strong.....the compression is pretty even right across all cylinders.... Any opinions or ideas?
 
Well you've done your homework, you have good spark (?) and you have good compression (?). It appears to me you only need to remove the carbs you have, clean and rebuild them, pull the plugs out of the pilot jet adjusting screw turn them after removal and replacement go 2 turns out for a starting point reinstall/start then tune when at operating temperature.. As others have mentioned before with a bike this old, or any year bike for that matter, you should check the tank for rust and if so repair or replace. Also get rid of the OEM fuel line and replace with Tygon as the old fuel line has proven to be a problem in the past. This is the prudent way. But! First check and make sure the tank is clean and not rusty and if so repair or replace. You can try a Poor Man's carb clean by draining the bowls then re-tighten the bowl drains pull the fuel hose off of the tank then fill the bowls and fuel line with carb cleaner then start the bike. Keep spraying carb cleaner in the fuel hose until the can is empty then let the bike die from lack of fuel, re-hook up the fuel hose turn the petcock handle to prime and fill the bowls then turn it back to the on position then take it for a ride and see if this has cleaned out the pilot jets etal. This may work if the pilot jet screws do not need adjustment but if it runs like a scalded ass ape after 4K RPM but bogs or lean surges below you need to pull the carbs anyway to remove the pilot jet screw caps to fine tune. "See the first recommendation." edited for: Synch the carbs before adjusting pilot screws. I hope this helps
 
Thanks, I'll try all of that as soon as I get back there....November. In the meantime, could this also be a valve adjustment problem? I've never done that.....but lots of info. on this forum from what I can see. Thanks again.
 
If you're not sure about the maintenance schedule of the bike then don't second guess and do the valve adjust. While at it check and make sure everything is in time by checking the cam gear marks in alignment with the horizontal lip of the head vs the 1&4 TDC timing mark behind the removable timing cover on the lower left crankshaft side. While in TDC position pull the cam chain tensioner and give it a once over. Change engine oil and filter, drain the final drive and pour in the proper type and amount of hypoid gear oil. To put it short and sweet if there is something that comes to your mind check it out because it's your butt on that bike and a safe bike means a safe butt.. :)
 
And to answer your question the valve lash adjust is something everyone who thinks they have no mechanical ability can do and say it's easy after they've done it the first time. Don't pull any engine side covers but use the starter switch to roll turn the lifters till the high part of the lobe is off the rocker arm preferably 180
 
I don't want to be bringing bad news but you should be aware that many of the 86's and possibly early 87's had problems with valves that were too soft and after 60K to 80K miles, depending on how much high RPM time on the engine, they are mis-shaped and you won't be able to maintain good valve lash clearances (because they stretch so fast) and if it gets bad enough, you won't have good compression. This could explain the reluctance to start. Do a compression test. I battled this problem for a couple of years and then at 62K, I traded in my 86 for the 01 I now have. The shop decided they wanted to "fix up" my old bike and sell it. Well, their shop bill for replacing all 16 valves and what ever else they did came to $2600.00. The sales guy told me the valves were so deformed you could have shaved with them.
 
I was just going to post this for Dempster to absorb; http://www.memberize.com/clubportal/mboards/viewmessages.cfm?clubID=1328&Forum=1406&Topic=19910 as I was not aware of the bad valves (tuliping) in the 86s until reading the included thread then doing some research in search. Yes Dempster, your valves "could be" a problem.. Sorry..
 
Okay, so the valves are on the list. Any idea what I need to do a good rebuild? Where to get new valves at reasonable cost? Also, might as well change out the camshaft and timing chain, right? Anything else I should start looking for? This job won't happen for awhile....but I can start looking for stuff now.
 
Dempster, the valve problem on the '86's is well documented but I don't believe all of the bikes were affected. I would do the carb cleaning and see how the old girl runs before diving into a rebuild. My .02 Good luck with your project. It sounds like fun. '02 Connie COG # 6662 Dallas, Tx
 
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