Wildguzzi.com
General Category => General Discussion => Topic started by: bigbikerrick on April 05, 2016, 07:27:25 PM
-
Hello Folks, I recently installed a dyna III in my Cal II, today I checked the timing with a timing light, and when revved to 3-4 K rpms, the "full advance" timing marks are way down in the hole , showing too much advance. when I turn the distributor to bring the mark s to the center of the window, the bike runs like crap, and wont idle. I had previously set the timing statically to the line below the "advance" mark on the flywheel, and it ran ok, but when checked with the light, it again shows way advanced at 3-4K rpms. I have a new timing chain, and bow type tensioner, I put in about 5k miles ago.Guzziology states to set timing with dizzy on "full advance". I tried that also, statically. any ideas?
I am going out to the garage to fiddle with the bike some more, will check back here a bit later,
Thanks alot,
Rick.
-
90 Mille advance is checked a 5K RPMs. Is it possible the Cal II engine is the same?
I checked my Motoplat and Dyna at 5K.
-
Maybe a new set of springs for the advance mechanism is indicated? If they were stretched or weak, you'd get too much advance and get it too soon, yes?
If I recall correctly, Guzziology addressed this in some detail.
-
Red Rider,I am not sure about the Millie, but I am suspicious its a different distributor. This one is a Marelli 311B I believe, the standard "low performance" dual point distributor.
Rodekyll,Fueling seems fine, I timed the right cylinder, then the left. I finished by timing both cylinders with the light, at full advance rpm( 4-5K), but the full advance mark has to be about 1/4" below the bottom edge of the inspection hole for the bike to idle, and run decent. The way the plate came set up from dyna, the left cylinder was firing a few degrees more advanced than the right, when I timed the right correctly to full advance, but the bike ran pretty good, when I timed both cylinders "equal" is when it really started running weird. It has an uneven idle, and throttle response is not as "crisp" as it should be.
Thank you for your help, fellas!
Rick
Rick
-
Maybe a new set of springs for the advance mechanism is indicated? If they were stretched or weak, you'd get too much advance and get it too soon, yes?
If I recall correctly, Guzziology addressed this in some detail.
I think the advance is limited by the design of the weights/mechanism on this distributor, and most of the instructions Ive read state to time it using the full advance marks and locking the distributor at full advance with a washer under the central bolt, to hold it at full advance (static) or spin the motor up to 4-5k RPM, and check the timing at that point.That is why I am thinking ,in this case, the springs are not as crucial, such as in a loop frame distributor. ( single point)
but then again, I may be wrong....
Rick.
-
I'd start by winding the left cylinder up to TDC on the compression stroke and put a WOODEN dowell down the plug hole to check you are at exactly TDC and check the mark on the flywheel, if you find it to be correct, Somehow fit a degree wheel to the front of the crank and set the degree wheel to zero on a pointer. Next wind the engine forwards almost two revolutions and with the point gap correctly set, watch for when they JUST start to open, that's when you will be getting your spark, and check the degree wheel that it's all happening at the right degree of advance when at full retard, it should be close to TDC, I would find out what the correct value is for idle revs, at this point I'd check that the mark on the flywheel is in the right position and remedy as necessary. Lastly I'd then hold the distributor on full advance and check on my degree wheel how far in advance the flywheel is when the points are opening, that will tell you if the stops are correctly set on the advance mechanism. The main point of fitting the degree wheel is to check the correctness or otherwise of the timing marks, they should be ok, but checking them manually will tell for sure. Just a thought.
-
Line up static mark at idle and it'll be fine, dizzy stops advancing at 6K so ring it up if it's not there.
-
Hola Rick,
Another possibility is that the (full advance) timing marks are not correct, for whatever reason.
If you feel that everything is set up right, and the bike idles & runs well with smooth, progressive throttle response, and is returning expected MPG, then I would make my own full advance timing marks using white fingernail polish or paint.
Best of luck!
Sean
-
Thanks guys for the responses, Huzo, I think you have a good point regarding using a degree wheel to check things out for sure. Sean, you point is a good one too. Ive read somewhere that some flywheels had the marks in the wrong place. The degree wheel should point that out. I dont have a degree wheel,in my toolbox, will have to get one today. I can time the bike "by ear" and get it to run great, I actually took it up to 95 mph yesterday( not bad for a convert with bags,full fairing, and lowers) after timing it by ear, but I guess I am too OCD to do it that way, and just leave it be. I would have nightmares about burning holes in pistons! :wink:
Rick.
-
Are the 2 cylinders synced? The problem I've had with the Dyna is getting the runout on the sensor wheel withing spec. The instructions call for no more than .005" I've found that if the runout is too great, one cylinder will time and the other will either be unstable or way off. The last one I did, I added a tiny hunk of .004" shim stock to get the runout in spec. FWIW
-
Thanks guys for the responses, Huzo, I think you have a good point regarding using a degree wheel to check things out for sure. Sean, you point is a good one too. Ive read somewhere that some flywheels had the marks in the wrong place. The degree wheel should point that out. I dont have a degree wheel,in my toolbox, will have to get one today. I can time the bike "by ear" and get it to run great, I actually took it up to 95 mph yesterday( not bad for a convert with bags,full fairing, and lowers) after timing it by ear, but I guess I am too OCD to do it that way, and just leave it be. I would have nightmares about burning holes in pistons! :wink:
Rick.
yeah I'd certainly check out the timing marks first
-
Mebbe someone had the flywheel off and reinstalled incorrectly. Been known to happen. Or is a Vert flywheel keyed?
-
Mebbe someone had the flywheel off and reinstalled incorrectly. Been known to happen. Or is a Vert flywheel keyed?
dont know for sure, this vert has the heavy cast flywheel. The PO did have the flywheel off the bike to re seal the engine at one time.
Rick.
-
Ok folks, Got it figgured out....Yes I am a dummie! I had the marks on the flywheel screwed up, and the degree wheel helped me "see the light" . I actually had the second line up from the "D" and the "S" erroneously marked as the "full advanced " mark. I realized the full advance mark is WAY up on the flywheel,about a couple inches. I marked the proper lines with white paint, then statically timed both cylinders using a test light, to the full advance marks, with the dizzy locked in full advance position. All is well, when I hook up my timing light, now I can see the paint marks in the window at 4500 rpms, but the thin white line appears very wide when lit up by the strobe, about 1/2" wide in the opening..... Is that an indication of the timing chain being loose, or is it normal?
Thanks again, and sorry about the mixup!
Rick.
-
Do you mean it's blurred and looks 1/2" wide, or is it a narrow line bouncing around in a 1/2" wide area?
-
Do you mean it's blurred and looks 1/2" wide, or is it a narrow line bouncing around in a 1/2" wide area?
Exactly, what I was trying to describe,Jim. The thin line is "blurred" and appears 1/2" wide. I tried to center it the best I could in the bellhousing opening by slightly turning the distributor after setting the timing statically. I had to advance the distributor about one degree, when checking it with the strobe, from the point where it was set statically at full advance.The bike fired right up, like it should, and revved freely with no hesitation, so all sounds good to me. I am going for a test ride, here in a few minutes, it looks like a beautiful, classic Arizona sunset this evening and the temps are in the high 70's.....any excuse for a ride! :grin:
Rick.
-
Ok folks, Got it figgured out....Yes I am a dummie! I had the marks on the flywheel screwed up, and the degree wheel helped me "see the light" . I actually had the second line up from the "D" and the "S" erroneously marked as the "full advanced " mark. I realized the full advance mark is WAY up on the flywheel,about a couple inches. I marked the proper lines with white paint, then statically timed both cylinders using a test light, to the full advance marks, with the dizzy locked in full advance position. All is well, when I hook up my timing light, now I can see the paint marks in the window at 4500 rpms, but the thin white line appears very wide when lit up by the strobe, about 1/2" wide in the opening..... Is that an indication of the timing chain being loose, or is it normal?
Thanks again, and sorry about the mixup!
Rick.Nothing to be sorry about ! Helping others out tends to sweep out a few dusty corners of our own knowledge, and may give someone the chance to tell us where we may be wrong ourselves. As for your fuzzy line wiTh the 'strobe, if the 1/2" wide line is static, it means the strobe is firing at he correct time each 2nd rev, but if it's appearing too wide, I'd say that the light is remaining on too long each flash. Probably try another 'strobe.
-
Sorry Biggie, I obviously buggered up that post but I certainly hope the guts of it was some help.Huzo.
-
You do realize that the sensors can be moved independently for final
adjustments so you don't have to move the dizzy. That
Way you can move one sensor at a time without screwing up the
Timing on the other cyl
TOMB
-
You do realize that the sensors can be moved independently for final
adjustments so you don't have to move the dizzy. That
Way you can move one sensor at a time without screwing up the
Timing on the other cyl
TOMB
Yes, Tomb, I was aware that the sensors can be moved individually, thats what I had to do to time the left cylinder, after setting the right one by moving the distributor, but thanks for checking on that! you never know.
Huzo, the white paint mark I made on the flywheel, appears "Fuzzy" when illuminated by the strobe, and" wide" , but you can see it move downwards (advance), as the engine is revved, its just difficult to tell when the line is exactly in the center of the round hole, as it appears about 1/2" wide.
Thanks again,
Rick.
-
Yeah Biggy, I'd have thought that the only way for the line to appear less than crisp or focussed if you like, would be that when your light flashes, it stays on too long allowing the mark to move a few mm while illuminated rather than an instantaneous flash whereby the mark has not moved appreciably for the duration of that period of illumination. How's that sound ?
-
Have you tried another 'strobe ?
-
the spark has a period of time that it works and that time is supposed to stay the same regardless of engine rpm. engine rpm though changes and when it increases it moves more in the same period of time that the spark is active. That means the flywheel is moving through a wider arc in the same period. But the strobe is lit for the same amount of time. So it is illuminating more of the flywheel arc and you are seeing that motion. It's like photographing an accelerating object at the same shutter speed -- eventually it elongates and blurs. a good strobe can dial that out. a cheap one may or may not.
set the timing to the farthest light point from tdc.
Thanks for the technical explanation RK, it makes perfect sense to me. My timing light is a cheapie, Ive had since the 70's when I was a teenager. I think the brand is "Hawk", and it uses only the power from the plug wire, there is no battery connection, so I have to darken the garage to use it. I need to get a better timing light for sure. The bike is running very well with the Dyna III, and setting the timing statically first, but using the proper marks on the flywheel this time got it darn close to where it should be, I think.
Thanks again,
Rick.
-
Have you tried another 'strobe ?
I need to get a better strobe, Huzo. What you describe is a simplified version of the same as what RK stated, in a more technical way. I may try to borrow a better timing light from my neighbor this evening, and do a re check.
Thanks,
Rick.
-
the spark has a period of time that it works and that time is supposed to stay the same regardless of engine rpm. engine rpm though changes and when it increases it moves more in the same period of time that the spark is active. That means the flywheel is moving through a wider arc in the same period. But the strobe is lit for the same amount of time. So it is illuminating more of the flywheel arc and you are seeing that motion. It's like photographing an accelerating object at the same shutter speed -- eventually it elongates and blurs. a good strobe can dial that out. a cheap one may or may not.
set the timing to the farthest light point from tdc.
That's a damn good explanation, you won't need to hear more than that.