Topic: My long-overdue Spark Advancer post...

[PeWe]

It's nice to have stable and clean idle ~1300-1500 rpm at red lights and when warming up closer to 2000 rpm. I do not trust too low rpm's and still have proper oil pressure where the cam need it.

An interesting thing I've noticed about this, PeWe: if the idle is even and smooth, the oil pressure will be good at even 1000 RPM, even with "hot" cams. For example, I've repaired engines that had a bad valve, which caused it to idle roughly and have very low hot oil pressure even to the point of flickering the oil light at idle, then fixed the valve and ended up with 50 PSI hot oil pressure, no other work done to the engine. It seems to be real sensitive to the smoothness of the suction from the tank.

Thanks Mark, I'll feel better when I have lower idle.
I got my new springs from Yamiya today. Quick shipping from them as usual.
Lets see when I can compare the rpms of full advance. Springs might affect the ramp of how fast the full advance will be reached as well.

[Jerry Rxman Griffin aka MuthaF'er]

My Yamiya order arrived with springs today also. Ordered Christmas day which would have been early Friday for them. They beat the other 4 orders from the States and still had to clear Customs. My US orders may not be here until next week.

They look lighter but I haven't compared them yet. 

[scottly]

Jerry, I wouldn't bother trying to measure the springs with a spring-scale. Instead, please measure:
1. the diameter of the wire
2. the number of full coils

[Jerry Rxman Griffin aka MuthaF'er]

0.75mm
10 turns

Is there a translate tool that someone can use and repost this??

[dave500]

it says not to bother about getting too fussy with it,look for poor alignment between the mounting face dowell alignment and the actual index mark,dial in tdc to be sure if your going to futz around with honourable spring tensions etc,the rest of it is just rude!something about falling on your sword if you cant time 1/4 and 2/3 perfectly or something.

[Nic]

it says not to bother about getting too fussy with it,look for poor alignment between the mounting face dowell alignment and the actual index mark,dial in tdc to be sure if your going to futz around with honourable spring tensions etc,the rest of it is just rude!something about falling on your sword if you cant time 1/4 and 2/3 perfectly or something.

Brrffff, good one Dave 

[KRONUS0100]

checked out in barn.............one of these is off a k2 and the other is off a k4...............not sure which is which or if they are indeed stock for the motor they came off of

both are .035 wire diamter
one is .228 outer diamter and the other is .208 outer diamter
the .228 one is .452 long minus the hooks and is 9 coils  the .208 is .470 long minus the hooks and is 10 coils
both are 300 series TEC parts
both are cb750

found this interesting because someone said 1 spring size was 500 and the other was 750 possibly

[Jerry Rxman Griffin aka MuthaF'er]

That translates to 0.89mm wire thickness vs the Yamiya 'racing' springs at 0.75mm. I use mm since these are metric bikes and the numbers are more frequently metric.

So far we might deduce the 'racing' springs do NOT have as much tension therefore would open up easier. Only thing about this deduction is the actual tension which might vary due to the type of wire used.

Thanks for posting. Guess I need to dig around the basement and find mine too. If any different I will post the numbers.

[scottly]

just don't ride under 3-4000 rpm and it wont matter what advancer you have,even pulling away youll rev the engine say 3000 and above when slipping the clutch,if not you should be.

You've got a good point there, Dave, as long as the advance returns to the 10* F mark (750s) at or slightly above idle speeds.

[Bodi]

Translation - by someone who doesn't know what the instructions are for:

*Spring size is 21mm type. When you removed it from original one, spring length must be 22mm or over.
You can’t use if spring length is 19mm.
*This product point is you can feel power up by replacing governor spring.
*If F mark is unsteady right & left, you can fix it by when you put point mark of timing right.
*This is electrical component so, you must install at Motor bike shop.
* At first remove #13 (2 bolts) then #10 point cover off.
*Then put a mark on #12 (3 bolts) and crank case for #2 disc.
*If so, you are not going to mess timing setting.
*Next remove #15 bolt then remove #12 (3 bolts), remove #1 point board from the crank case.
*Then pull #7 governor off.
*Then remove #7 governor center steel pipe.

Caution
*When you remove pipe, make sure take a note fat part of pipe and bottom Groove position.
*you can install it if Groove positon is backward, but #1 & #4, #2 & #3 timing will be backward, so you can’t turn on engine.
* Then replace the spring. Spring shape is different between right and left.
Put the way where a gap isn't open in a shaft.. Hang the way where a gap is open on a hole.
Caution
*Do not pull the spring too much. Install it as minimum as possible to stretch.
*Install it Contrary to a removed way
* Check timing & Bolt tightness again.

[scottly]

Ah so, thank very much, Bodi-san.

[Jerry Rxman Griffin aka MuthaF'er]

Thanks Bodi. Now we have to translate Japanese English    Always helps if you follow instructions.

By the way, those are the instructions that came with Yamiya 'racing advancer springs'

[scottly]

I've made some progress with the SOHC dynamic ignition test rig. The pics were taken with it running at 2600 RPM. I put it together with stuff I had laying around: the motor came from a Razor mini chopper, and the orange bearing carrier and timing pulleys and belt came from a CNC plasma cutter that Henry and I put together 20 years ago. I still need to make some small parts to center and clamp the points plate(s) down; I made it to be adaptable to different versions. I engraved timing marks at 5* increments for a total of 45*, in case I want to test a system with no timing marks.
With no load (points), or point cam, I've spun it up to about 10,000 RPM, but it seems the point cam adds a noticeable amount of imbalance, as the thing started walking across the bench as soon as I cranked the speed up.  

[HondaMan]

Very cool, Bodi!
 
Can you attempt a chart of the advance rates of the various types?

[Herr Supersport]

Gentlemen

I know it’s keen to burst into a discussion between experts – anyway, I feel free to present some results concerning the Yamiya-springs. Ordered Friday last week the stuff was here Wednesday. Congrats to Yamiya, to the Jap- and Swiss-Mail, that’s brilliant.

I measured the dimensions of the springs, stressed them with a weight to get the spring rate and crosschecked with an internet calculator. So it should be possible to see if they are similar to original parts. In my case 333-advancer/CB 350/400f  [results in brackets].
What I saw:
•   Wire diameter: 0.80mm [0.81mm]
•   O-diameter of spring: 5.19mm [5.89mm]
•   Total length: 21.0mm [20.5mm -> not original, I shortened them some times ago]
•   Number of turns: 10 [7]
•   spring rate with load: 4.9N/mm [4.9N/mm]
•   spring rate calculated: 4.8N/mm [4.7N/mm]

I think the Yamiya-springs are very near to the originals – but note that 750s may be different. Perhaps somebody could do the measuring of these to clear if the Yamiya-parts also fit a 750.

Of course I was curious how it works. It’s cold here and I didn’t want humidity in engine and muffler. So I mounted the advancer in the lathe – it starts opening at about 1300 / full opened at about 2600 revs. Obviously that’s not as exact as with the strobe but gives an idea. When the temperatures rise I’ll check on-bike and possibly shorten one or both springs a little bit.

So – I hope this precious thread will continue, it helped me a lot.

Greets, Daniel

[HondaMan]

Gentlemen

I know it’s keen to burst into a discussion between experts – anyway, I feel free to present some results concerning the Yamiya-springs. Ordered Friday last week the stuff was here Wednesday. Congrats to Yamiya, to the Jap- and Swiss-Mail, that’s brilliant.

I measured the dimensions of the springs, stressed them with a weight to get the spring rate and crosschecked with an internet calculator. So it should be possible to see if they are similar to original parts. In my case 333-advancer/CB 350/400f  [results in brackets].
What I saw:
•   Wire diameter: 0.80mm [0.81mm]
•   O-diameter of spring: 5.19mm [5.89mm]
•   Total length: 21.0mm [20.5mm -> not original, I shortened them some times ago]
•   Number of turns: 10 [7]
•   spring rate with load: 4.9N/mm [4.9N/mm]
•   spring rate calculated: 4.8N/mm [4.7N/mm]

I think the Yamiya-springs are very near to the originals – but note that 750s may be different. Perhaps somebody could do the measuring of these to clear if the Yamiya-parts also fit a 750.

Of course I was curious how it works. It’s cold here and I didn’t want humidity in engine and muffler. So I mounted the advancer in the lathe – it starts opening at about 1300 / full opened at about 2600 revs. Obviously that’s not as exact as with the strobe but gives an idea. When the temperatures rise I’ll check on-bike and possibly shorten one or both springs a little bit.

So – I hope this precious thread will continue, it helped me a lot.

Greets, Daniel

Those sound very close to the OEM advancer numbers, back when the bikes were new. That's a good sign.
Nice work!

[scottly]

I rigged up a coil and a couple of plugs so I could use the timing strobe today. The TEC 300 K7 advancer seemed to max out at 20*, vs the marked 25*, but I need to do more testing, as well as get it hooked up to the scope.

[Jerry Rxman Griffin aka MuthaF'er]

Keep at it Scottly. It seems the Yamiya springs did not arrive in NJ as anticipated. Thinking the USPS sorting machine ate the envelope. It had both the intended address and a return address. Hoping it will get repackaged and sent to one or the other. If it occurred at my PO then it may be hopeless. Farging idiots (and that's the nice version)! 

[scottly]

I found the missing 5* of advance today: the springs only had about .5mm of preload, which allowed the advancer to move 5* by only 600 RPM, as it took up the slack. From that RPM upward the timing was stable until about 1400, at which time the advance began.

[Don R]

 Bump,  this was linked on FB today, I wondered if it could be put in faq's or tips and tricks.

[Don R]

 I looked in my stash today, have a couple nice tec 300's a 323 and Hitachi early advancer. I had marked a set of 300 weights to grind a little more advance stop clearance into them, never did.

[HondaMan]

I've made some progress with the SOHC dynamic ignition test rig. The pics were taken with it running at 2600 RPM. I put it together with stuff I had laying around: the motor came from a Razor mini chopper, and the orange bearing carrier and timing pulleys and belt came from a CNC plasma cutter that Henry and I put together 20 years ago. I still need to make some small parts to center and clamp the points plate(s) down; I made it to be adaptable to different versions. I engraved timing marks at 5* increments for a total of 45*, in case I want to test a system with no timing marks.
With no load (points), or point cam, I've spun it up to about 10,000 RPM, but it seems the point cam adds a noticeable amount of imbalance, as the thing started walking across the bench as soon as I cranked the speed up.  

Gorgeous rig, Scottly!
I wish I'd had something like that with the last new advancer I just bought for a 750F2 I just rebuilt. The springs in it were so strong (it is a new unit from 4into1.com) that at 4000 RPM it was only advancing 15 degrees, not quite halfway up the curve. I got a lighter spring from a sacked-out AD125 advancer and replaced one of them, then it made full advance by 2800 RPM, just about right.

The new advancer is mechanically well constructed, but it has much, much too strong springs. Not a bad deal for the $60-ish it cost.

Balanced? Heehee...yeah, right... It would take a lot more holes drilled into the baspelate to pull that off in one of these! The best of the balanced ones came from Hitachi, the worst from TEC (which is also what this new one was). The Hitachi ones are quite rare now, it seems.

[StockRider]

My advancer was fairly gummed up so I took it apart for cleaning. I did not note the alignment of the cam before disassembly. DOH!

HondaMan's first image shows the alignment mark pointed away from the Hitachi symbol. mystic_1's image (in Reply #7) shows the mark pointed at the symbol.

Which way should the cam be aligned?

[jonda500]

50:50 - can only go two ways. It is correct when you don't have to swap over the blue and yellow points wires to get it to start!
John

[HondaMan]

My advancer was fairly gummed up so I took it apart for cleaning. I did not note the alignment of the cam before disassembly. DOH!

HondaMan's first image shows the alignment mark pointed away from the Hitachi symbol. mystic_1's image (in Reply #7) shows the mark pointed at the symbol.

Which way should the cam be aligned?

Which one do you have? They 'point' to different features on the baseplate, depending on which one.