Regardless of the ignition system e

Regardless of the ignition system employed, the spark plug must fire at the correct
time if good power is to be made and engine damage avoided. Some two-strokes are
timed to spark at 2mm before TDC, others at anywhere from 0.4mm to 4mm.
Probably you are wondering why the difference? Well, first, the length of the engine's
stroke will affect the amount of advance required. A short stroke engine with 2mm
advance will have considerably more advance measured in degrees of crankshaft
rotation than a long stroke engine with spark timing of 2mm before TDC. For
example, a 125cc engine with a stroke of 60mm and 2mm ignition advance has 18.8°
advance, the same as a 125 engine with a 50mm stroke and 1.65mm advance. The
advance angle can be calcuated using the formula:-
A= Co S P
2
+R2
-L*
2xPxR
where A = ignition advance in degrees
R == engine stroke divided by 2 in mm
L= con-rod length (usually stroke multiplied by 2) in mm
T = ingition timing in mm
P= R + L-T

Hasil (Bahasa Indonesia) 1:

Terlepas dari sistem pengapian dipekerjakan, busi harus kebakaran di yang benarwaktu jika daya yang baik untuk dilakukan dan mesin kerusakan dihindari. Beberapa dua-stroke yangdiatur untuk performa 2mm sebelum TDC, lain di mana saja dari 0.4mm sampai 4mm.Mungkin Anda bertanya-tanya mengapa perbedaan? Yah, pertama, panjang mesinstroke akan mempengaruhi jumlah muka yang diperlukan. Pendek stroke mesin dengan 2mmAdvance akan memiliki jauh lebih maju diukur dalam derajat crankshaftrotasi dari panjang stroke mesin dengan percikan waktu 2mm sebelum TDC. Untukcontoh, 125cc mesin dengan stroke 60mm dan 2mm pengapian muka telah 18.8°Advance, sama seperti mesin 125 dengan 50mm stroke dan 1.65mm muka. Thesudut Advance dapat menggunakan rumus calcuated:-A = Co S P2+ R2-L *2xPxRmana A = pengapian kemajuan dalam derajatR == mesin stroke dibagi oleh 2 mmL = panjang con-rod (biasanya stroke dikalikan dengan 2) mmT = waktu ingition mmP = R + L-T