Hi folks,
Been off the forum for awhile fiddling with my SuperHawk rebuild, but I recently decided to try and get my rebuilt Dream to run better (it's never run as smoothly and strongly as I thought it should, and seemed to foul plugs periodically). I always struggled to get the timing set right, so after futzing with the points statically and dynamically timed that seemed to wander around sporadically, I finally got fed up and bought one of the electronic units from Charlies Place. The installation instructions were somewhat obtuse, but I got them installed (note: I have also replaced the R/R and the coils, wires and plug caps), and once statically timed, the bike idled smoother than it ever had, and revved nicely. I put my timing light on the thing, the idle timing was nice and steady (finally) on the F mark, but when I revved the bike, I could only get the advance to go less than half way to the II mark. Puzzled, but not too concerned since the bike was running nice and smoothly, I jumped on the bike and took it out on the street, but even thought the start out was good, the bike had no poop to accelerate. I brought the bike back to the garage and pulled out my timing light and manually advanced the magnetic pickup on the camshaft until it wouldn't go any further, and holding it there, slowly rotated the engine until the timing light came on - right at the II mark, full advance. Started the bike up, put on the dynamic timing light, and with the bike screaming, the furthest advance it would get was about halfway to the II mark. WTF, can the advance weights hang up? when I rotate the advance manually, I don't feel any stickiness or hang up - has anyone seen anything like this before? Note, while riding around, slowly coaxing it to accelerate during what appears to be at it's halfway advance condition, every now and then it will rev very briefly, with a short surge, then goes back to noodling along, like its sporadically going to full advance. About the only thing that I can say is that it is running so much smoother during all this - at least the electronic ignition has erased the previous points uncertainty. In retrospect, I think that when i had the points in there I had the timing way advanced at idle, such that as I accelerated, I was getting the advance to the II mark (or a little beyond) so it appears that this has been happening even when the points were on there.
So before I drop the engine to look at the advance mechanism, has anyone seen anything like this so I can make sure that I fix the problem? Or maybe I'll just buy one of those Sachse ignitions so I can just bypass the damn advance weights and springs....
Thanks in advance,
Jack
Yet another weird advance problem
RE: Yet another weird advance problemHi Jack: (Don't say that loudly in an airport....)
One thing to check is your cam chain tensioner, to be sure there is no excessive rotation/movement in the camshaft. If there is, you won't be able to get the timing right, no matter what you do! Good luck, CJ ------- '66 CB77 '66 CP77
CJ,
Thanks for the observation on the cam chain tensioner, I will definitely check that when the mill comes out. I've been researching the timing issue before dropping the engine, and after following jlovvorn's odyssey with his super hawk, I'm beginning to think that I might be looking at the same issue. Since my Dream smoked like a chimney once I got it started from it's 20 year slumber, I went ahead and popped it open and replaced the rings and gaskets. I put it back together, but have had a lot of problems with getting the bike running right since and saw erratic ignition as well as issues similar to jlovvorn with the timing, i.e., not being able to keep the advance from going beyond the II mark, etc., - this led to the gradual replacement of the coil, plug wires, and I finally added the electronic ignition in an (apparent) misguided attempt to get it running more reliably. I used Bill Silver's manual to set the cam timing, but I think I might have the timing off a tooth - tomorrow I'll test the compression to see if it's low as jlovvorn observed in his engine. I'll also look at the cam tensioner since that could be impacting the cam timing as well. It sure seemed like a simple engine when I tore it apart... Thanks for the pointer, I'll let you know what I find out. Regards, Jack
Hey Jack, I am no expert and Ed would be your best source. However, for what it's worth, if the cam chain tensioner does not fix the problem, maybe your issue is one of the following; 1. When you put the cam chain back on, hopefully you didn't miss allign the cam and crank marks. Being off by one tooth might cause your problem; 2. You might want to look at the advance mechanism and replace worn out springs. JMHO, and I might be spittin in the wind.
Good luck. P.S. Again Ed Moore would be a great source, he is soooo, soooo good on these things.
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