Problem with timing my Convert

[bigbikerrick]

Hello, Folks, I am having problems getting the timing right on my Convert,after replacing the roll pin that holds the distributor gear on. I installed the distributor per Guzziology,with new points and condensers, and I modified the mounting plate for the left cylinder points to allow for more timing retardation. I have the right cylinder timed correctly, it hits right at the full advance mark, when revved up, and at idle the TDC static timing mark is just below the hole, in the bellhousing as expected, since its partially into the advance curve at idle.  Even with the plate mod, I cant get the left cylinder properly timed, as you rev the bike, the full advance mark goes well past the "window" by about 4-5 teeth  on the flywheel past the full advance mark.
The bike runs, but it idles poorly, and stalls out. Carbs are rebuilt, clean, and synched properly.
anyone have any idea what I should do next?  I do have a Dyna III ordered, but I would like to get the bike running right with the points, so I can ride it, until the dyna gets here.
Thanks
Rick D.

[Antietam Classic Cycle]

"Fudge" the point gap - more open or closed to get the timing correct.

[bigbikerrick]

Thank you, Charlie. I will give it another try, with a fresh head of steam... I  have tried "fudging" the point gap,  making the gap for the  left points much smaller,and also larger,  trial and error ( mostly error  )and I could still not get the left cylinder to time properly. Ive done dual point tonti distributors before on my Lemans,and Cal II. This one is weird for some reason, I have been working on it trying to time it and to idle correctly for 3 days!
Rick.

[n3303j]

Absolutely sure you haven't confused S and D and have the timing set on the wrong set of points.
Reducing point gap retards timing.
Increasing point gap advances timing.

[bigbikerrick]

Thanks Ron, Im pretty sure I didnt do that, I dont think the bike would start that way,but I may be wrong. The Top set of points  times the right cylinde, and the bottom set that is on  a separat plate is the left cylinder. I set the right at .017" and the left at .014"  , but tried different combinations of gaps, to see if it would run better. no luck.  I am going to re do everything, starting from the beginning, and see what happens.
thanks
Rick.

[n3303j]

Depending upon distributor placement either set or points could run a cylinder and have the other cylinder incorrectly timed. With 12 teeth on the distributor driven gear there are 11 wrong places to mate it to TDC on compression for each cylinder. And if you grab the wrong cylinder I think that gives you 23 wrong places?

Bottom line. The differential firing is built in by the shape of the points cam and locations of the points. The bike ran fine before it changed its timing relationships by shearing the pin. So, if you have it assembled correctly it should run as it did before the pin sheared.

Meanwhile, if it were my machine I'd be curious why the pin sheared. Curious enough to totally disassemble the distributor and replace the bearings and seals. That's just cheap insurance.

[bigbikerrick]

Thank you Ron. when I had the distributor out I disassembled it, replaced the o rings, but not the bearings, they turned very smoothly, with no discernable play on the shaft.  If the distributor gear went back into mesh one or two teeth off either way, would  that not be adjustable when you turn the distributor to adjust timing for the right cylinder? So long as it is not way off.  I went back and re did everything, regapped both points , left at .014" and right at .018 "fudging" like Charlie recommended, and  with the plate for the bottom points at full retard position, the timing is pretty darn close to where it should be. I noticed a miss on the right side , and since I was running it with the distributor un capped, I could see sparking at the right points corresponding with the miss, I could also see it when I hook up the timing strobe light to the right plug wire, it would "skip" a flash of the light.
 as a test, I hooked up the lead from a chevy v8 condenser, I had on hand to the points screw, and the sparking /miss stopped, I removed the lead, and the sparking and miss would return! Bingo! Winner winner, chicken dinner! I think my bad idle/ missing was caused by a faulty , (brand new ) condenser, I had just bought, along with points etc.

Oh well, Many thanks to all that helped me, you guys rock!  I am happily awaiting the arrival of the Dyna III, so I can forget about condensers and points for a while.
Rick D.

[chuck peterson]

Condensor!…congrats!

[bigbikerrick]

Muchas Gracias muchachos! This one has been a  bit of a "head scratcher" for sure.  Whats the deal with brand new condensers from the usual suspects turning out bad? I have dealt with many point ignition vehicles in the 60's and 70,s  mostly air cooled Bugs, and dont remember new condensers turning out bad, very often, actually I dont really remember any of the new stuff being bad. I used alot of "Echlin" brand ignition parts` with good results. there must be some source for good quality condensors being available.

Anyway, after a frustrating day, I was happy to take   the convert for a 30 mile test ride last night, and it didnt miss a beat. c

[Antietam Classic Cycle]

Whats the deal with brand new condensers from the usual suspects turning out bad? I have dealt with many point ignition vehicles in the 60's and 70,s  mostly air cooled Bugs, and dont remember new condensers turning out bad, very often, actually I dont really remember any of the new stuff being bad. I used alot of "Echlin" brand ignition parts` with good results. there must be some source for good quality condensors being available.

It seems to be a common "thing" now, I'm not sure why. Thankfully, I have a small stock of MOS Marelli and Echlin condensers to use. HMB Moto offers this, which looks promising:
https://hmb-moto.de/Capacitor-module-all-models-with-2-contact-breakers-T3-LM1-LM-2-etc

You can also "roll your own":
https://www.thisoldtractor.com/moto_guzzi_loopframe_condenser_-_create_your_own.html

[bigbikerrick]

Thanks for the info, Charlie. The one from HMB Moto looks much better, than anything else currently available.     I think I am going to order one, Although I have installed a Dyna III  in the convert I plan to throw my point plate in a saddlebag as backup , since this is going to be my "tourer".
Rick

[n3303j]

Never thought of mounting the capacitors at the coil input, rather than the points. What a nifty idea!

Two less wires to deal with at the points and distributor. Also less heat on the capacitor.