96 yamaha bravo no SPARK

[Waylon]

Hey , got a yamaha bravo longtrack 250 cc

its just died on my with no spark
. I tested all switches , they ok, multimeter says ignition coil is
good, spark plug cap is good, spark plug is good.

Only things left are the stator coil and cdi. I have no idea how to
check cdi, i checked the stator coil and am getting 260 ohm at 0
degreees. my manual is giving me specs for a 250 t and a 250tj, its a
older manaual and do not know which one is correct. the manual states
the 250t should be at 275 ohms at 20 degrees, and 250tj at 425 at 20
degrees.

[Stig Arne Bye]

Post by Waylon
Hey , got a yamaha bravo longtrack 250 cc
its just died on my with no spark.
I tested all switches , they ok, multimeter says ignition coil is
good, spark plug cap is good, spark plug is good.
Only things left are the stator coil and cdi. I have no idea how to
check cdi, i checked the stator coil and am getting 260 ohm at 0
degreees. my manual is giving me specs for a 250 t and a 250tj, its
a older manaual and do not know which one is correct. the manual
states the 250t should be at 275 ohms at 20 degrees, and 250tj at 425
at 20 degrees.

Because the CDI unit contain multiple electronic components (SCR,
capacitor, diodes and resistors), it is very difficult to check the CDI
unit by just measuring it using a standard multimeter. There are some
CDI testers available, except they will not handle all kind of CDI units
due to differences in construction between them.
With my prior experience in repairing some CDI units, it's usually the
SCR or power transistor (some CDI's have a power transistor instead of a
SCR) that is fried as the SCR is acting as a contact less switch that
switch on and off the ignition coil pulses and thus carry a higher
current flow than the other components. The other components in the CDI
unit are for controlling the pulse triggering of the SCR (or transistor)
by discharging of a capacitor, timing advancement, engine kill etc.

Your stator coil seem to be OK, as long as your measurements don't show
0 ohm (short circuit) or infinite (broken winding).
In addition, there is usually a tolerance of +/- 10% of the specified
coil resistance, so a coil specified to for example 300 ohms could be
measured anywhere within the range 270-330 ohms.



Stig Arne Bye

92 Yamaha VT 480 TF/E (Venture)

E-mail ......: ***@footballfans.co.uk / ***@football.clubs.io
Contact .....: MSN Messenger: ***@footballfans.co.uk
Snail-Mail ..: Axel Borgens veg 4, NO-9900 Kirkenes, Norway
Homepage ....: UNDER CONSTRUCTION: http://stigbye.football.clubs.io
------------------------------------------------------------------------
Located just about 70°N 30°E - Almost at the top of the world!

[Lynn]

Post by Waylon
Hey , got a yamaha bravo longtrack 250 cc
its just died on my with no spark
.  I tested all switches , they ok, multimeter says ignition coil is
good, spark plug cap is good, spark plug is good.
Only things left are the stator coil and cdi.  I have no idea how to
check cdi,  i checked the stator coil and am getting 260 ohm at 0
degreees.  my manual is giving me specs for a 250 t and a 250tj,  its a
older manaual and do not know which one is correct.  the manual states
the 250t should be at 275 ohms at 20 degrees, and 250tj at 425 at 20
degrees.

Ignition connectors need to be perfect. I had fixed some by simply
cleaning and them plugging in and out a few times. Try this first.