Author Topic: cdi for 1974 mx 250 yamaha  (Read 6149 times)

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Offline jimg1au

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cdi for 1974 mx 250 yamaha
« on: July 08, 2008, 11:06:14 AM »
any of the listed below will work
Part # = 364-85540-13-00
Part Description = CDI UNIT ASSEMBLY
Model Count = 10
MX250A 1974 250 MX250 Off-Road
MX250B 1975 250 MX250 Off-Road
MX360A 1974 360 MX360 Off-Road
YZ125A 1974 125 YZ125 Competition Motocross
YZ125B 1975 125 YZ125 Competition Motocross
YZ125C 1976 125 YZ125 Competition Motocross
YZ250A 1974 250 YZ250 Competition Motocross
YZ250B 1975 250 YZ250 Competition Motocross
YZ360A 1974 360 YZ360 Competition Motocross
YZ360B 1975 360 YZ360 Competition Motocross
cheers
jim

Offline Freakshow

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Re: cdi for 1974 mx 250 yamaha
« Reply #1 on: July 08, 2008, 11:40:31 AM »
these 10 06 series Cdi's are probally hardest part on the mx to find,  you will probally guess that as you see what else they fit.

IF you have a dead one , steve warne can still fix them but its about $200 or so.   They only ever come up rarely and if they do on ebay they still get good money and with no sureity that a 35 yr old gel pack electronics will still be working right as they are usually of a breaker.    

YOu can get aftermaket versions ( see lozza) but the debate is the ignition curves etc, at least you know with the originals they are right, although i have never seen these ign advance on a timing light so i dont think they do although the book says they do, so in theory a replacement should work fine, but hey who knows.

A whole PVL will set you back $4-600, inc stator, coil and black box, half the weight and 10 time more spark and spirit, might be a better option if you are keeping this bike.
« Last Edit: July 08, 2008, 11:43:36 AM by Freakshow »
74 Yamaha YZ's - 75 Yamaha YZ's
74 Yamaha  flattracker's
70  Jawa 2 valve speedway's

For sale -  PRE 75 Yamaha MX stuff, frame, motors and parts also some YAM DT1,2,A and Suzi TS bikes and stuff


Offline vandy010

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Re: cdi for 1974 mx 250 yamaha
« Reply #3 on: July 08, 2008, 01:24:57 PM »
5 wires= red
            black
            brown
            white/red stripe
            white with green stripe

i've not done it myself but am led to believe a later model CDI from a DT or YZ with 4 wires will do the job.
the differnce being the white/stripe wires.
one colour matches up and you run the other one to ground and they can be found on ebay for as little as $15
worth a shot
"flat bickie"

Offline Freakshow

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Re: cdi for 1974 mx 250 yamaha
« Reply #4 on: July 08, 2008, 01:53:02 PM »
Interesting   mr vandy....   more info please.
74 Yamaha YZ's - 75 Yamaha YZ's
74 Yamaha  flattracker's
70  Jawa 2 valve speedway's

For sale -  PRE 75 Yamaha MX stuff, frame, motors and parts also some YAM DT1,2,A and Suzi TS bikes and stuff

Offline crs-and-rms

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Re: cdi for 1974 mx 250 yamaha
« Reply #5 on: July 08, 2008, 07:28:39 PM »
i have a cdi from  a yz 250 b that i bought  for the owner of a bike shop i worked in but he sacked me before it arived from the usa  it is a hitachi and has tla01 - 06 408  has two plugs with three wires  to it and one with two wires to it  it has been repaired at some time as it has a alloy plate siliconed to its back

Offline vandy010

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Re: cdi for 1974 mx 250 yamaha
« Reply #6 on: July 09, 2008, 01:54:05 AM »
Interesting   mr vandy....   more info please.
the dude that rewires my stators here in brisbane told me so freaky. he also went on to say that a CDI from a different manufacturer would also work but the colours of the wires will be different {he lost me at that point} and then he said, oh no, it'll only work if they're type %$#@ or whatever {and i could feel a beer coming on}. so i got lost in his blurb. but what i did get was,
EG, some DT175 CDI's are 4 wires from stator,
             =red
               black
               brown
               white/red stripe
so, we run the white/green stripe from the MX250 stator to ground.
if it's hard to start or backfires/misses then swap the two white/striped wires around the opposite way.
this is all i understood but am yet to try it.
perhaps someone else has got the scoop on this. but worth a shot!
"flat bickie"

Offline jimg1au

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Re: cdi for 1974 mx 250 yamaha
« Reply #7 on: July 09, 2008, 07:06:10 AM »
vandy
can you pm me his phone no as i have a few dt360 stators i need checked out and repaired also a it400 ans sc500 complete ignition
cheers

Offline vandy010

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Re: cdi for 1974 mx 250 yamaha
« Reply #8 on: July 09, 2008, 10:22:44 AM »
pm sent Jim
"flat bickie"

Offline jimg1au

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Re: cdi for 1974 mx 250 yamaha
« Reply #9 on: July 09, 2008, 12:50:31 PM »
thanks
i got it
cheers

Offline TT5 Matt

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Re: cdi for 1974 mx 250 yamaha
« Reply #10 on: July 09, 2008, 10:25:58 PM »
okay most jap systems have a high voltage [200v so dont fork with it] charge coil the other smaller coil is a pulse or trigger coil which puts out very low voltage [less than 4-5 v] which tells/trigger the charged up cdi and high tension coil to turn off thus ceatating spark as we know it,some more modern yamaha systems 80s on had low and high speed pulse coils with that said yes you can use black boxes from other jap makes,what the colours are cant remember as its 10 years since i spannered bikes to earn a crust but if you know how to read factory workshop manels/wiring diagrams and can use a multimeter it can be done.i hope it helps someone out there

TT5 Matt                                                         

Offline vandy010

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Re: cdi for 1974 mx 250 yamaha
« Reply #11 on: July 10, 2008, 12:15:00 AM »
it's all a step in the right direction, thanks Matt.
"flat bickie"