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Aussie TT2 track bike build
http://www.ducatittandf1.com/viewtopic.php?f=10&t=2434
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Author:  Carlo [ Sun Mar 23, 2014 9:15 am ]
Post subject:  Re: Aussie TT2 track bike build

if I understand correctly, the bike was not, because the pic up were reversed between them?

sorry.....my englis.....

Author:  wdietz186 [ Sun Mar 23, 2014 2:02 pm ]
Post subject:  Re: Aussie TT2 track bike build

Steve, When you set the pickup/flywheel gap try and stay toward the wide side of the spec. If too close it will act like it is stuck on full advance, sort of like flipped polarity. Had that problem with my wifes Allazura on cold start it would barely crank and it would fart and bang alarmingly.

Author:  Pantah600 [ Tue Mar 25, 2014 2:25 am ]
Post subject:  Re: Aussie TT2 track bike build

:? Sig Carlo, no problem. The pick up positions are not aligned to TDC of the horizontal cylinder as is required. I am about 10 deg out to the timing marker. :oops: I thought I could find TDC easily by aligning the cam timing marks and screw driver feel in through the spark plug hole (very carefully mind you)... but I was not exact in my check.
The horizontal pickup polarity is reversed. This I have confirmed. The timing light was showing it to be about 30 deg advanced in the spark. So this was causing the plug to foul and become very sooty. I can fix this easily enough with a terminal tool...I seem to recall Graeme the kind soul suggesting to use an old car ariel antenna.... I don't have one of those older cars....
The main thing is to get a degree wheel and a dial gauge to triple check TDC and finally position the pickups.

Thanks for the tip WD! I had set them at 0.4mm only in the wrong position!

Will report on the outcome soon.
Cheers,
Steve

Author:  Carlo [ Tue Mar 25, 2014 9:41 am ]
Post subject:  Re: Aussie TT2 track bike build

I know that you will solve your problem very soon, I am very confident.

I would like to say one thing, if this can help you.

If you put the references of the timing belt pulleys perfectly aligned, without looking at the timing comparators, you put the pic up correctly, and thickness gauge with the captors of four tenths of a millimeter ..... the bike is working well now . then if we make a very accurate timing, it is still <better the job done. I hope I was understood.

Ciao Carlo.

Author:  Pantah600 [ Wed Mar 26, 2014 4:24 am ]
Post subject:  Re: Aussie TT2 track bike build

;) Sig. Carlo.... Perfetto!
Lo capisico bene.
When are you coming here? Do you have extra TT2 decal kit available?
Cheers,
Steve

Author:  Pantah600 [ Sun Apr 06, 2014 7:16 am ]
Post subject:  Re: Aussie TT2 track bike build

:? Gents,
I'm seeking your guidance to my on going issue regarding the bike not behaving as I'd like.
Especially in reference to Dellorto carburettors....

Previously, I had the issue with timing and pick-up positions. That is now sorted. Horizontal TDC and pick-up gaps set to 0.4 clearance to the highest step on the flywheel.
The timing is about 3 degrees advanced.

Upon further investigation, I had some dodgy wiring connections at the connector block which I re-crimped and solded correctly. Then the wiring at the Bosch terminals was wanting also. Now they are re-crimped and solded. Then, I had incorrectly wired the ignition coils to have the +/- reversed. That is sorted now too.
Now, I have consistent strong sparks, ignition coils not burning my fingers to the touch.... Starts like a dream...

Except, my carbs are not balancing nicely. I can't get a consistent idle and it's either revving high or stalling. The idle adjustment screws make a difference, the air/fuel mixture screws don't. It will both idle high for a while then the revs fall to a stall... It is slowly returning a normal idle then will stall...

Carburettor rebuild history: PHF36 AD Horiz. & AS Vert.
New float valve and seats to standard specs.
Float levels set to spec @ 17.5mm
New gasket kits and standard pump jets.
Cleaned idle & main jets of standard specs. Except have noted that the K4 Needle is set to top notch not the 2nd as specified.

Engine setup: Modified Giannelli 2 into 1 exhaust shortened with F/Glass wrapped steel perforated baffle
Carby trumpets: open gauze Mallossi short 38mm

What carby modifications would you suggest I use for this setup listed above please?
Return it to a standard spec or go larger with the jets?
I'm all ears!
Cheers,
Steve

Carby:
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Exhaust:
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Assembly155.jpg [ 216.7 KiB | Viewed 494 times ]

Author:  618F1 [ Sun Apr 06, 2014 10:47 am ]
Post subject:  Re: Aussie TT2 track bike build

Some say that a larger needle jet will solve this problem (I may have read this in the book Guzziology); it may be that the idle is set high and the jet cannot fill the bowl quick enough. Thus, high idle followed by a stall. If using a 250 then go to a 300; if using a 300 then go to a 350. Using 350 has worked for me. I am sure many other suggestions will be forthcoming.

I also see you use a K4 needle, when a K2 is stock for a 36mm, and K5 is for a 40mm.

MikeV

Author:  huit [ Sun Apr 06, 2014 11:10 am ]
Post subject:  Re: Aussie TT2 track bike build

Good calu Mike, the only other thing is to make sure that there is no air leaks, or air being sucked in
Good luck
Paul

Author:  wdietz186 [ Sun Apr 06, 2014 12:03 pm ]
Post subject:  Re: Aussie TT2 track bike build

Take the carbs apart, remove the jets, using carb cleaner make absolutely sure the idle circuits are clear. On the engine side, behind the slide is a tiny hole which is the outlet for the idle circuit. If you block the pilot jet hole and spray through the mixture screw hole you should get cleaner coming out the tiny hole and also out the air hole at the front of the carb. Compressed air is a big help here too. On badly clogged carbs I've used some really fine wire to clear the hole but it is a bit risky because if it breaks off in there you are f*ck'd. When the circuits are plugged you can get sort of an idle with the idle screws run way in but it is inconsistent because the fuel is being drawn up from the needle jet and doesn't atomize well and it coughs when you open the throttle because it goes way lean when the slide lifts.

Author:  corsa [ Mon Apr 07, 2014 1:04 am ]
Post subject:  Re: Aussie TT2 track bike build

I'm going with wdietz186. I reckon a blocked jet/passage etc..
Let us know what you find.

Bike looks awesome by the way!

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