Anyway, I noticed something funny about my feeler gauge on the way to following Herr Joel's (aka Groundhog, aka ZombieStomp) recommendation to check the valve clearance. the .002" strip looked unused. You can tell they've been used because they get kind of bent and abused in order to reach into the valve ports threaded into the rockerbox cover. Which meant I couldn't have had my intake valves adjusted properly. 0.004" exhaust. 0.002" intake. OK! Well rechecked the exhaust and they looked okay. I checked the intake and they were too loose. Too loose because I was able to pass a 0.003" feeler through the tappets. So I carefully made it possible to cinch up that last 0.001" and crossed my fingers.
Started first kick just fine and sat there idling with the choke on while I called Dad so that he could hear the engine over the phone. Damn hot however. The header completely discolored and had some blueing proximal to the exhaust manifold. Few minutes and then a backfire and some smoke. I don't ahve a screen in the airbox so sometimes the flames puff out into the filter which is not good and why I got the fire extinguisher in the first place. Time to shut off and hope nothing bursts into flames. Plastic gas tanks don't do so well against fire, nor do airboxes or all the other fiberglass shit I've made. Damn it's hot. Hope it settles but at least it seems promising on try number three:
Damn, man. No temp. gauge dipstick to tell you exactly what's going on in terms of temperature either. I do know that lots of plates make the bike tend to be more lean. Your spark plug doesn't tell us much since you had it running on choke most of the time. California models (such as yours) were jetted even leaner than the other non- Calis that I still hear people bitch about being too lean. '83s have bigger carbs and richer jets. Go down to about 4 plates and look for the next two sizes up for jets. That is if you have no intake manifold area leak.
ReplyDeleteNo but I do have an instant read thermometer in my kitchen; using the same bimetallic strip principle that the XR's Only one employs so I could use that I suppose. Honestly, Joel, the cylinder heats up so fast before the frame warms up; there probably is some heat loss (I hope) before the recirculated oil makes it to the temp gauge throwing off the read.
ReplyDeleteI also still might be a little low on oil (~200Ml) so that could also explain some of it.
Lean jets also could explain some of the hot I suppose. I know I have the mains up 2 sizes to 120. I'll have to check what the pilot is at, which is the trouble here I assume.
The fuel/air mixture is another potential issue.
PO had ground off the tab to recalibrate. Default is 2 turns out where I'm at right now. I'll try backing it out to 3 and see if that makes a difference.
Also will remove a few discs from the muffler since it's too loud anyway -- I know I'll never want to ride it at that level. I hate loud pipes.
The aspect re the intake valve clearance or any valve clearance, is to guard against having them not open enough. If you get the valve clearance too tight - let's say overly tight (too small clearace)- then the valve might not ever close properly. That would be very bad indeed causing some blowbye and with prolonged use - damaged valves.
ReplyDeleteIf the excessive engine heat is mainly concentrated in the cylinder and not the head then the main source for that is essentially ring friction - a common artifact of a rebore. I'd keep running that damn thing to get the rings seated.
Sounds good. Lemme give it a spin...
ReplyDelete