yamaha XT/TT/SR 500

[LWC82PE]

im working on a 500 yamaha that i cant identify what it is and what electrics it has as im trying to trace a running problem.

checked manifold for leaks first as i thought it may have been a air leak, but couldnt find anything there, so im thinking its now ignition problems.

whats the easiest way to tell what engine it is? the bike is a bit of a bitsa. im not sure if its a 500 motor in a XT550 frame or if its had a 550 or early IT/YZ mono shock rear adapted on. it has a alloy swing arm.

it has a nippon denso CDI unit marked

3H1 (or 3HI) -50
ND 070000-051 0

wires

white/green
brown
white/red
orange
black/white
2 blacks
red

i think it might be SR500?

do TT 500 have CDI?

all i have is the cylmer manual up to 81 for TT/XT 500

i want to test the pulser coils resistance to see they are not breaking down.

is there any info on the web for any electrical specs or wiring diagrams?

someone has changed the wires comming out of stator so now i have to take off flywheel to get in and check colours

thanks for help

[caps 999]

3h1 = 1980 sr500 

[LWC82PE]

ok. what should be the colour wires comming out the stator?

have you got any SR 500 electrical specs/tests

[caps 999]

sorry i just know the prefixes but got no diagrams sorry but someone here should

[Marc.com]

one of your blacks is brown.

brown/white,
white / red
black
red
brown

coil side of CDI

blue/black
red
black

[LWC82PE]

none of those colours match what i got here. i found SR 500 specs in a yamaha fast facts book and the colours they give for the source and pick up coils match what i got comming out the motor except for one colour. the book says red but i have a pink, so i think someone has just used a pink instead of red.

ignition wires i have comming out stator are

white/red
white/green
brown
black
pink (ment to be red??) - the whole loom comming out the stator has been extended so maybe reason using pink was they didnt have red.


so far it looks like a crook source coil. cant get the flywheel off yet. i got a puller but the bitch still wont come off yet

also has any one got the SR 500 stator ignition coils specs just so i can be sure what the book i have says is correct as i dont fully trust it as its not a genuine yamaha publication.

[Colin Jay]

This is the modified wiring diagram for the SR500 electrical system that I run on my XT500C road trial bike.



All the wire colours are as per the std factory wiring and you shouldn't have much trouble isolation the the ignition wiring from the lighting wiring.

CJ

[LWC82PE]

thanks colin i will have look now

actually  can you email it to me a bit larger as i find that a bit hard to read. my email address is on my profile. thanks

[Colin Jay]

Done, hopefully the large file is more readable.

CJ