Tony Need Your Help 81 Srx 440

S

SRX540

New member
Joined
Nov 16, 2010
Messages
86
Location
Ontario, Canada
Ive got the older stator (3 pronger) for my 81 SRX Tony and two CDI's where one of the serial numbers end in "38" and the other end in "39" which set up do i use. What set up do i use ???
 

THERE WERE TWO CDI,s USED ON THE 81, THE PREFIX,s WERE 8K4 (very rare) AND THE 8R9 (almost all had these). ALSO ALL THE STATORS/ CDI ALONG WITH CASES WERE UPDATED. WHEN YOU SAY OLDER STATOR, I ASSUME YOURS WAS NOT UPDATED. I GUESS YOU NEED TO SEE WHICH ONES PLUGS IN. 3:16 (yammie tony)
 
Last edited:
- Stators 5 different
1981 SRX (Original) P# 8K4-85500-10-00
1981 SRX (Updated) P# 8R9-85500-10-00
1983 Vmax P# 8U9-85510-10-00 without the hand warmer coil
1984-86 Vmax P# 80N-85510-10-00 with the hand warmer coil
1987-1991 Vmax P# 83H-85510-10-00Yamaha changed the charging coil in the stator to a higher output coil, by doing this the secondary coil output went up from 18,000 volts to 28,000 volts ,but you also have to use the 1987-91CDI as well as, it is different to accommodate the higher voltage of the charging coil in the stator.
F.Y.I. Double check P#'s !

-CDI's
1981 SRX 440 P#8K4-85540-10-00
1981 SRX 440 (Updated) P# 8R9-85540-10-00 it is used with the 8R9 stator
1983-86 Vmax P#8U9-85540-10-00
1987-1991 Vmax P# 83H-85540-10-00

http://www.vintagevmax.com/vvforum3/viewtopic.php?f=2&t=1529
 
so which one do i use?????

I have the 3 pronger, should i use that?? I have the 8R9 stators i have 3 of them, can i use the 3 pronger stator with the 8R9 cdi??
 
8R9 one is way better then the original 81 is, alot more aggressive timing curve.
 
mrviper700 said:
8R9 one is way better then the original 81 is, alot more aggressive timing curve.
Click to expand...


Not saying you are wrong because I don't know but I've been told just the opposite by guys I know that ran them back in the day. I've never gotten a clear reason as to why from them but that was the claim.

Would be interesting to know what is best/better, under what circumstances and why.

A lot to lay out/walk down I know so don't put yourself out. It would be nice to see what the differences are someday.

opsled
 
Hey Phil, no offense taken.

the original srx cdi put out a flat timing curve, this curve was only 8 degerees.

The "new 8r9" box is the srx500 box, this cdi gives 12 degrees MORE advance at 5000rpm then the original 81 box, the curve is steeper thru out the rpm band and ends in near the same degree point. For those of you adding this up, yes, it has 20 degrees advance at 4000rpm, not 8. They did this is help accel. the engine and it ended up working and making more power all the way thru the rpm curve(which isnt very big on a srx440)...lol

the curve retards as the rpm goes up for topend power, ends at the same 8 degrees at 9000rpm
 
Last edited:
FUNNY PHIL I HEARD SAME THING. THE 8K4 WAS WAY BETTER FOR RACING. I CAN,T SAY BECAUSE MY 81 WHICH STILL LIVES TODAY WAS ALL UPDATED TO 8R9. AGAIN, ONLY GOING ON WHAT I WAS TOLD BY AFEW REAL GOOD DEALERS BACK IN THE DAY THAT SOLD THESE NEW. 3:16 (yammie tony)
 
yo

I got too ancy and just put the 4 prong stator with the 8R9 CDI is this a good setup? i hope it doenst grenade on me. Hey Tony im on excitersx with you also been fixing up the SX i found in some guys back yard last week....
 
yo

Hey TOny i put the 4 pronger on with the 8R9 CDI is this a good set up?? I also have a v-max bottom end on it. I live in southern ontario so how should i set up my jetting for the butterfly carbs??
 
mrviper700 said:
Hey Phil, no offense taken.

the original srx cdi put out a flat timing curve, this curve was only 8 degerees.

The "new 8r9" box is the srx500 box, this cdi gives 12 degrees MORE advance at 5000rpm then the original 81 box, the curve is steeper thru out the rpm band and ends in near the same degree point. For those of you adding this up, yes, it has 20 degrees advance at 4000rpm, not 8. They did this is help accel. the engine and it ended up working and making more power all the way thru the rpm curve(which isnt very big on a srx440)...lol

the curve retards as the rpm goes up for topend power, ends at the same 8 degrees at 9000rpm
Click to expand...


Thanks. I've got a bunch of 81 stuff and both types of ignitions. My youngest want's to finish an 81 mod project of mine that's been on the back burner for a few years and was going to use the 8M6 ignition when I build the engine because of what I was told. Sounds like the 8R9 is the better way to go.

Thanks again, Phil (opsled)
 
JET IT SAFE, ALL I CAN SAY HERE. I WILL SAY YOU BETTER RUN NO LESS THAN 100 OCTANE IN THIS 81 OR YOU WILL BE LOOKING ALOT FOR PISTONS. 3:16 (yammie tony)
 
YAMMIEGOD3:16 said:
JET IT SAFE, ALL I CAN SAY HERE. I WILL SAY YOU BETTER RUN NO LESS THAN 100 OCTANE IN THIS 81 OR YOU WILL BE LOOKING ALOT FOR PISTONS. 3:16 (yammie tony)
Click to expand...


Won't be to radical. Cleaned up ports otherwise stock. Roundslides, 44's? probably. But yes Tony, I will keep it safe.

Thanks,
opsled
 
yo

I put regular in the v-max and it runs fine, wont it run better since the regular gas makes a bigger bang or will the better gas lubricate better and prevent burn down. FYI Tony, had the 79 EX 440 out yesterday man that thing is so fun in drifts!!!!
 
I had one of these 81 srx's i really liked it sounded great was fast for its time the only issue i really had was i pic'd it the drive axle is aluminum,the gear is steel and in a very short time i spun the the splined shaft smooth.was a real week point .they should of used a steel drive shaft with the steel gear but after i replaced the drive i pulled the pic's never had another issue
 
You must log in or register to reply here.


Back
Top