SUGO CDI for Borut... (ignition curves)

[Yuri]

Which one are you still missing?

3xv70 & 3xv75

I am about to have a 3xv75 for xmas.  you guys still need it?

Yes it is still needed !

It arriveed!  Who should I send to?

To Juergen
I will pm you his address

[jools]

I wonder what a 3YL would look like in comparison?

[41juergen]

I would think not so much different as it was only 2 years earlier and still AVGAS. But If someone has one I would be happy to test it...

[Yuri]

I wonder what a 3YL would look like in comparison?

I think that it will be less advance on the old TZ's the head volumes was smaller...

[EEKNOWS]

I wonder what a 3YL would look like in comparison?

Unremarkable .I do have the curve on my now crashed external HD but this is fairly close

[jools]

I would think not so much different as it was only 2 years earlier and still AVGAS. But If someone has one I would be happy to test it...

I have a spare one I could loan so that we have an accurate comparison.
(as long as I get it back  )

send me a PM Jurgen

[maccas]

Was the 4DP tested with the same flywheel as all the 3xv ones Juergen? I'll have to dig out my spreadsheet and see what that would be with the 4DP-10 flywheel.

Dan

[41juergen]

Dan, I got the matching flywheel with it and tested it in the correct setup. Later I made a test with the (smaller) 4DP or 5KE flywheel (don't know the exact model year), but there was no difference on the ignition timing. At least with the accuracy I can read of the degree wheel.
@Jools: PM send...

[maccas]

Ah brill!

The only thing is that the initial advance for the 4dp-10 model should be 18 degrees, not 21. So i think the curve should be dropped by 3 degrees?

Dan

[41juergen]

I'm not sure Dan about the need for dropping 3°CA. I measured also the Zeel where I put the 20°CA curve in to (kind of) calibrate the system and than re-checked the 4DP data. The output was as shown... I would believe that the 4DP would also fit to the higher advance requirements for AVGAS?

[maccas]

But in the 4dp manual the ignition timing is quoted as 18 degrees (well the equivalent in mm before tdc).

The user is supposed to adjust the ignition pick ups so that the rear of the lobe on the flywheel corresponds with that figure. Then the timing is as yamaha designed. If you set that figure to 21 degrees then you are advancing the ignition by 3 degrees because the distance between the front of the lobe and rear of the lobe is fixed.

Does that make sense? I'm not knocking what you are doing i think it's great. But that is what would make sense to me.

Plus i'd expect the 9A curve to be very similar to 4DP as they run the same fuel and very similar engine/pipe spec etc?

Dan

[41juergen]

Agree with you on the "mechanical" part how to setup the ignition timing on a TZ. But I'm wondering what happens inside the CDI after getting the impulse to start the spark. It will take some time to calculate that point and the power must be inducted. So may be that's the reason that the mechanical adjustment don't necessary must be the same as the ignition timing? And as said, I believe with the Zeel putting the 20°CA ignition timing in was some kind of calibration for the system. Also taking 3°CA of advance away the ignition timing at max. power point would be only 13°CA BTDC for an AVGAS engine...
But may be the guys having more experience with real race engines can give us their thoughts too?

[Yuri]

Just for interest sake here is the head vol of the 94 RSP

Translated

1) Machining the head cylinder Please process the head cylinder for TZR 250SP according to the following procedure at the time of SS race First measure the volume of the combustion chamber of the head cylinder of the basic car (spark plug NGK BR 9 EC mounted) Next Please cut the mating surface with the cylinder so that the volume of the combustion chamber becomes 9.5 cc (when the spark plug NGK BR 9 ECM is installed). At this time, please adjust the feed speed etc. of the cutter so that it becomes about the same level as the original processed skin. If the surface is too rough it will cause gas leaks, water leaks etc. The lower limit of the volume of the combustion chamber should be 9.3 cc. If it is less than 93 cc, the elongation will become worse. When the proportion surface is cut by 0.1 mm, the volume of the combustion chamber decreases by 0.25 cc when the spark plug (NGK B R 9 ECM) is installed. Note) Spark plug NGK BR9ECM is used for combustion chamber volume measurement only and should not be used for racing.

[Yuri]

92 RSP sugo head setup

Translated

4, ss Processing for racing and incorporation 1) Machining of head cylinder Please process the head cylinder for TZR 250 SP according to the following procedure when SS racing. Please scrape down the mating surface to the cylinder evenly to 0.2mm. If you scrape over 0.2mm, the piston and head skimmer become strict and cause trouble. At this time, please adjust the feed speed etc. of the cutter so that the surface roughness is the same as the original processed skin. If the surface is too rough, gas leaks, water leaks etc will be caused. When the mating face is cut by 0.2 m, the volume of the combustion chamber becomes 9.3 to 9.4 cc when the spur plug (NGK BR 9 ECM) is installed (9.8 cc when STD is NGK BR 9 ECM installed) Compression ratio 8.0 → 0.3 to 8.4 Note) Spark plug NGK BR9ECM is used for combustion chamber volume measurement only and should not be used for racing.

[jools]

Juergen

last night I located 2 x 3YL CDI's. They are both labelled but have different packaging, which seems odd for a model in existence for only 1 year. Also the denso part numbers are different. Can you measure PV opening without a controller ? Do you need the flywheel too ?

I'll send them both but I can't recall if the PV controller is integral. I'm using a 4DP10 on the bike at present. I sent these both off for testing to make sure they were ok but never got around to fitting preferring the smaller, lighter 4DP flywheel.

cheers

Jools