auto advane unit

[yamchop]

i'm having troubles with the advance unit on my 72. i replaced the springs but the weights stick open alittle. what can i do to fix it. i know theres some thin washers in there how many and where do they go exactly?? i may hve them wrong.

 

[tx650]

Have you got new springs and are they the correct ones?
I had the same problem with one of my Xs's and found out that they are a certain type.
Just make sure the points end of the cam is lubed but do not overdo this as the lube will fly off onto the points,just a smidgeon is enough and you should be able to turn the shaft by hand (engine not running of course) and it should return by itself.Re the washers,well just use enough so there is hardly any side to side free play and enough room for the c clip.
I have seen the springs listed at Mikes Xs.
Good Luck.

 

[yamchop]

i bought the springs at mikes. not much free play on the weights. is there saposed to be a washer between the weight and the c clip?

 

[Sundie]

there is sometimes a wave washer between the weights and base unit. This is not a disaster if you don't have it.

Mike's springs are a bit loose for my taste. I like taking one loop off, so that advance doesn't come on fully until 3500, and doesn't start until about 1500. I've found with Mike's springs, advance is fully on at 2500, and comes on right off idle. YMMV.

 

[yamchop]

how do you take 1 loop off? i dont think i'm getting it?!?! would the new springs be to weak to pull the weights all the way back? they seem to just be haging up about half way open.

 

[XSLeo]

To take one loop off, you cut the current loop off and bend up the next turn of the spring to make a new loop.

 

[yamchop]

o ya duh stupid!! tried that still sticks open what next??

 

[jay760]

Have you made sure the rod runs freely through the middle of the cam? if it is stiff for some reason it might stop the springs from returning.

 

[CDNTX650]

as in, lube the advance rod. Disassemble the advancer and the nut on the other side where the points are and remove the rod to grease it moly grease.

 

[yamchop]

ok sounds good i'll try it. thanks

 

[CDNTX650]

i think it's posssible to re-install things 180* out and then the bike won't run too...so make a not of which way things went together/came apart.

 

[grizld1]

Leave the points cam nut alone. Loosen the stepped nut on the camshaft behind the ATU with a hammer and flat punch and move the whole assembled ATU toward the end of the camshaft as you loosen the stepped nut further. With the ATU removed, you'll see a pin in the ignition rod. Paint mark the side of the rod with the pin in it for reassembly and pull the pin out; you've just assured yourself of correct phasing. Remove the rod from the breaker points side.

 

[cheftay]

i'm also having some trouble with my advance unit, well mostly the rod. I just installed the whole cam after overhauling my engine and i replaced the bushings inside the cam with Part #05-0033 http://www.mikesxs.net/parts/img250/05-0033.jpg from mikesxs. they fit flush against the outer rim of the cam.

but now when i got to put the rod through it's a very tight fit it takes a wrench to be able to rotate the rod... i'm not the brightest guy ever but this strikes me as NOT good.
also i'm able to wiggle the bushing out of the cam and back in... i'm not sure if that's good either.

thanks!

 

[yamchop]

well took the rod out cleaned it up put some moly grease on reasembled and still sticks. WTF!! any other ideas?

 

[xsjohn]

Sounds like the bushing has to be slightly enlarged inside......could some fine sandpaper be glued to a dowl and the bushing turned on it to open it a bit.....?.......as for those not fitting tight on the outside maybe some sealer of some sort.......?

xsjohn

 

[grizld1]

Cheftay, there are 2 sets bushings in the camshaft. What your link shows is the outer bushing, or labyrinth seal, which is there to retain grease. The inner bushing is a separate part; that's the one that supports the ignition rod. Since you can easily remove the labyrinth seals do so and check their fitment on the uninstalled rod, then slide the rod in part way and check resistance on the inner bushings one at a time to locate the bind. If everything moves smoothly when individually inspected, you'll know the bind is due either to a cocked bushing or to runout in the advance rod. Don't try to cure the disease before you've diagnosed it!

 

[pamcopete]

Take a look at the advance installation guide on the website:

www.yamahaxs650.com

There are a few tips there that relate to installation and possible causes of binding.

1. The spanner nut that holds the advance mechanism should have its lip to the out side. If it is on the inside, it can distort the position of the plate and push the locating pin in on the brass bushing which in turn will cause binding. (Weird!)
2. If the locating pin for the advance plate is too long, same deal. It will push in on the brass bushing and cause binding.
3. In general, it is a good idea to file the locating pin for the advance plate down just a bit to prevent binding.

 

[cheftay]

Haha thanks xs and grizld1, part of my problem could have been my lack of sleep but they seem to be spinning fine today... phewww