Are advance springs still available from Yamaha?

Mailman

Mailman

Hardly a Guru
Top Contributor
Messages
9,941
Reaction score
48,270
Points
688
Location
Surprise Az
I am considering replacing my advance springs, but I have read some bad reviews of the ones sold by Mikes. I also found a set on EBay for $20 which seems a little steep, and also of unknown quality.
I just recently serviced the whole advance unit, so everything is clean and lubed.
 
Unfortunately no, they're not available from Yamaha anymore. N.O.S. ones do pop up on eBay from time to time, just keep watching. Original price from Yamaha was about $7 each so if you can find them anywhere near that, I'd say go for it. You do want originals. I don't think there's a good aftermarket one out there. You may end up having to pay a bit more.

But, are you sure you need them? Have you tested your advance action? It may be a bit sluggish after a fresh greasing but that will loosen up after the grease gets worn in a little. Still, if you're into 650 ownership for the long haul and plan to keep using the mechanical advance, I think a back-up set of original springs is a "must have". I managed to pick up a couple sets over the last few years. Even though my originals seem a bit sloppy, they're still doing the job OK. Honestly, I've never put on a brand new set. They may look and act the same for all I know. On all the ones I've tuned for people, the springs were similar to mine but still worked fine, after an advance servicing that is.
 
5twins said:
Unfortunately no, they're not available from Yamaha anymore. N.O.S. ones do pop up on eBay from time to time, just keep watching. Original price from Yamaha was about $7 each so if you can find them anywhere near that, I'd say go for it. You do want originals. I don't think there's a good aftermarket one out there. You may end up having to pay a bit more.

But, are you sure you need them? Have you tested your advance action? It may be a bit sluggish after a fresh greasing but that will loosen up after the grease gets worn in a little. Still, if you're into 650 ownership for the long haul and plan to keep using the mechanical advance, I think a back-up set of original springs is a "must have". I managed to pick up a couple sets over the last few years. Even though my originals seem a bit sloppy, they're still doing the job OK. Honestly, I've never put on a brand new set. They may look and act the same for all I know. On all the ones I've tuned for people, the springs were similar to mine but still worked fine, after an advance servicing that is.
Click to expand...

Yup - that was my experience too. Whe I first started up Lucille, my advancer unit was sticky but after lubricating the two pivot points, it works fine. You may need to gently pop the little retainer clips off and remove the fly-weights and polish the little pivot shafts (just a tiny bit) with some emory cloth and reassemble it.

Just staring at those springs - it doesn't appear to me that they are stretched all that far and certainly nowhere near their elastic limit, so I doubt they would be worn out even after years of normal service.
 
Something to watch out for. The fly weights motion rotates the slotted disc. When your bike came from the factory, it was a very precise fit and worked quite well. But after all these years, the little ears on the fly weights have worn down such that it becomes a sloppy fit. The result is the advance range is expanded, and if you set timing for the correct idle position, the timing goes past the full advance position, when you are 3000 + rpm. As everyone knows, if the engine runs very long with the timing advanced past the full advance mark, it can burn a hole in the top of the piston.

Be sure to check carefully with your timing light.
 
Yamaha provided some adjustment to compensate for that. The idle timing spec is given as a 5° range, not just a single value (13° to 17° BTDC). The "F" mark in the center of the range is 15° BTDC. The full advance mark is 40° BTDC. A new unworn advance unit delivers 25° of advance so 15 + 25 puts you right at that 40° mark. But, as the unit wears and the amount of advance it delivers grows, you may end up past that 40° mark at full advance if you use the "F" mark for your idle setting. To compensate, you simply set the idle timing a little to the right of the "F" mark, more towards that little slash mark just to the right of the "F".

Vh8F2GU.jpg

Vh8F2GU.jpg
 
Last edited:
I'm really not sure if they are bad or not. I'm just trying to rule them out as the cause of my run away engine. When I timed the motor it was advancing just fine, but what I couldn't tell was if it is advancing too soon and causing the rpm's to climb of their own accord. I still have not resolved the air leak either. And right now the way the engine revs and falls by itself , it renders the bike completely un rideable.
The motor starts right up, but sometimes the motor just surges up to 3,000 rpm and hangs there. Then when I try to get the rpm back down by backing off the idle screw, it'll slow down so much the engine wants to die.
It's making me a little crazy.
That's why I decided to push up the install of my Pamco unit. I thought maybe it would help settle it down.
 
Mailman said:
...sometimes the motor just surges up to 3,000 rpm and hangs there...
Click to expand...

When it does that, simply apply a little drag to the 10mm nut on the points cam. Thumb and forefinger, lightly grip, as though you were to finger-tighten the nut. If idle immediately comes down, you've confirmed a problem with the advancer and/or springs...
 
Only after the air leakage (lean condition) problem is completely solved, should you chase other high idle potential problems.

If your experience follows mine, you will eventually get tired of playing with fly weights and springs, and buy the Pamco E-advancer.
The difference is like night and day. The E-advancer gives a reliable, linear advance curve that never changes. Second only to the Pamco itself, the E-advancer was the best money I ever spent on my bike.
Oh.................did I mention, I really like the E-advancer:laugh2:
 
Yeah I know I'm going to wind up getting one. I just kind of thought I could put that on the back burner for a while.
But yes we are in the same page regarding the intake leak.
 
So no new springs are found?

I'm searching aswell. I have 2 OEM uncut springs, 2 OEM cut springs. Im having trouble that my advance isnt 'linear'.
How linear should it be? with one cut and one uncut spring, it reaches full advance at 3k. but it looks like it 'jumps' in the advance curve from 2k rpm to 3k rpm.

I have just tried with one setup. Ill test with both uncut oem springs tomorrow. Have 2 new springs from heidentuning aswell ( same as mikes xs )
 
When i bought my bike i naturally thought these springs are old and new has to be good...right....Bought a set from Mikes and installed them, tested the spring back...........no, not happening, so reinstalled the originals and snap back was back.............Real time experience

if you wan't i can sell you a set of Advance springs i bough of Mikes that have been siting in the draw for a few years now.........no i wouldn't sell them
 
Make sure the advance rod through the cam is lubed up well. The factory recommends a grease with Moly in it. Once that is done, seemingly worn out springs may come back to life.
 
650skull: I have 4 OEM springs, and 2 new from mikes already. Guess ill have to play around a bit.

5twins: Advance rod is newly greased. Only one heat cycle with it, turned freely/easily without weights and springs in place. Maybe ill have to use 2 OEM springs, set the timing so its not over advancing and then go for a few rides and see if it needs to let the grease loosen up a bit and maybe the old springs could work. Otherwise ill play around a little with the springs i got, should be able to make it work.
 

Similar threads

I
Advance bob weights and springs question?
2 3
Replies
42
Views
1K
Its been a long time
I
R
My experience with the xs charge and XSCharge electronic advance ignitions
2
Replies
32
Views
3K
Flash1977
Flash1977
motormike
Muff ... ( as in muffler )
Replies
0
Views
227
motormike
motormike
N
Buying Someone Else's Project ('81 XS650SH)
Replies
11
Views
461
nexizen
N
L
Installing A Tri-Spark Ignition System
Replies
4
Views
2K
LTGTR
L
Back
Top