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Sooty saga follow up

You and I are on the same page DD. Had a set of Champions in last week and 1-4 wouldn't fire, even though I had spark. Put in the set of Iridiums I just bought and it fired right up. Spitballin' here, but what if the rocker adjustments are off? Would that cause loss of power as it warmed up? Either way I guess I will check them and the cam chain adjustment since I don't trust anything the PO told me (he said they were all adjusted recently and I don't hear much engine clatter).
 
Its possible if the valves are too tight it would cause valve to not close all the way. It would be a good thing to check them anyway.

I dont run Champions in anything...maybe a lawn mower. I have seen nothing but trouble with champions in the automotive world. They foul way to easy. I have replaced hundreds as a tech. I have had issues with iridium plugs also as far as fouling especially on older ignition systems. I have found it hard to beat the old NGK D8EA for the 750.
 
Agree on the Champions. I am going to get another set of NGK's. Would you suggest going a little hotter to a D7EA? I hope to talk to Ken tomorrow and get some more clarity on what the root problem is. Thanks.
 
Another thought. Can the needles be adjusted on the keyhole style carbs? Maybe set too high? Problem is that when it runs (even when it had 115 jets and upside down floats) it didn't bog from a stop or under hard acceleration so I am grasping at straws here.
 
Needles in keyhole carbs only came with one slot for the needle clip. You could change needles to a set with 4 slots, or use washers to shim the needles. Dunno if this is done in yours though. That's just how it's done.
From what you've eplained I don't think the needle position is your issue..
 
And about going on to hotter plugs. I have no personal experience on this but I've read a lot on it and running hotter plugs to make it run correct doesn't fix the actual problem. Timing, valves, advance or what ever it may be..
 
Stabler said:
Needles in keyhole carbs only came with one slot for the needle clip. You could change needles to a set with 4 slots, or use washers to shim the needles. Dunno if this is done in yours though. That's just how it's done.
From what you've eplained I don't think the needle position is your issue..
Click to expand...

Thanks Stabler. Given that this thing is stock with only 6,000 miles I doubt the needles where changed. However, it is nice to know what to look for when I open up the carbs for the third time. I am going to call the PO (in a nice way) to get some history on this thing. I am getting tired of guessing. Take care.
 
I think I am finally making some progress. Valve clearance was too tight, oil was black after only 80 miles, and the pilot screws out too far. When I had the carbs off the pilot screws were out 1 1/2 turns. I saw somewhere they should be out about 1 3/4 turns so I thought that was about right. I now have turned them in almost 1/2 turn. Plugs still a little black but without the fluffy coating. Clymer's has a procedure for setting the pilot screws so I'm thinking I should start there. It says to use an electronic tach to monitor the RPM drops. Anyone know where to get the one of those?
 
I have never used a tach, just done it by ear. Turn in till motor runs rough...note position....then turn out till motor runs rough...note position and turn back in till halfway point between the two points you turn the screw too. If that makes sense.
 
dirtdigger said:
I have never used a tach, just done it by ear. Turn in till motor runs rough...note position....then turn out till motor runs rough...note position and turn back in till halfway point between the two points you turn the screw too. If that makes sense.
Click to expand...

Yup, that makes sense DD. I talked with Ken this morning. He also suggested it might be a plugged gas cap vent. The vacuum would eventually prevent gas from flowing to the carbs. That #2 carb pilot screw is a bugger to get to. Any tricks you have learned?
 

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