May 1, 201610 yr Hi all , Can someone please tell me how soon before TDC the points should open and the gap to set them, Weak spark and I am unable to see them opening at all, Thanks.
May 1, 201610 yr Googled it...... Yamaha specs for this bike are : timing is 3.1 mm BTDC point gap .012" to .016"
May 1, 201610 yr Author Thanks Spen , I take it that the points start to open 3.1mm before TDC, I cannot understand why I now have a weak spark as I did not touch the points when stripping the only other thing maybe that where the HT coil fastens to the frame it not making a good earth due to the powder coating ,....?????? What you think Kind Sir.
May 9, 201610 yr I have a 74 and have good spark after some chasing. I am no expert but here's my $.02 worth... If the coil has bare brass mounting surfaces - like the guys said already - clean the bike's mating/adjacent surface and add some light oil against rust - see "faying surfaces" for a boat load of rubbish on this that says A Good Ground is important. Manuals are on line - cheap and comes via email and a then a cd a few days later. It knows stuff. Ask the guys with the Spanish made bike what they wouldn't give for a decent manual! Remove the ignition back plate and unplug the cable. On the bench - Clean the bell housing inside diameter with 400-600 - cleaning only! Blow or wash sanding dust away. A light coat - thin film - a spray of WD40 is okay. Spray it on and wipe it clean. Remove and replace the condenser (or chase it for the next six months - up to you) Clean or replace points (if needed change the points adjusting/mounting Screw too). The points are set @ <.015" and burnished with a match book or business card - 'til it comes out clean. Check harness at the gromet where it exits the engine case. Stiff wire here is a failure wating for some vibration. It could work part time/intermittent - as mine did or may create a high resistance path and weaken coil response - not sure but I do know stiff wire that should be flexable is bad. Good luck - no school like old school! For good reason - of course.
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