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Aussie TT2 track bike build
http://www.ducatittandf1.com/viewtopic.php?f=10&t=2434		 Page 22 of 24
Author:  Pantah600 [ Mon Apr 07, 2014 3:12 am ]
Post subject:  Re: Aussie TT2 track bike build
:P Thanks my good fellows!
I'm stripping the carbs tonight and making sure the float levels are spot on.
Mike, I'm certain the Pantah 36's use K4 needles as standard? Are you suggesting I use K2 instead? I'm willing to try that. However, I'd like to first try the clip on the 2nd or even the lowest notch.
WD, I used compressed air when I rebuilt these carbs and replaced all the gaskets. The only thing I didn't replace was the diaphragm and the main jets. But, I made bloody sure I cleaned them. The only thing I can't be certain of, if the previous owner had the jets drilled out or if they are indeed stock. Maybe, I should just replace them to be Irish...sure.
Mike, I can increase the float needle and seat as you suggest. But, I should also tackle 1 step at a time....otherwise, I'm getting on the piss.
Lee, thanks mate for your kind words. This last bit is the most time consuming aspect.... For a novice such as I.
I could just give to young Brad, but the poor bloke is flat out. At least I can get it close enough to run. I need a Dyno!
Thanks to all again!
Cheers,
Steve
Author:  ducadini [ Mon Apr 07, 2014 3:56 am ]
Post subject:  Re: Aussie TT2 track bike build
check the mixture screws, there are two different types.
I have a tool to measure jets upto 0.01 mm. Should be available in a decent tool-shop.

ciao
ducadini
Author:  Pantah600 [ Mon Apr 07, 2014 7:35 am ]
Post subject:  Re: Aussie TT2 track bike build
:cry: Well Gentlemen, we have found out many things again without rose coloured glasses on!

I thought I had stock standard Dellorto's PHF36's!
They are far from standard according to the workshop manuals. And the strangest thing is.... the 2 that I have are FOREVER telling me 2 very different things!
So, things for you all to digest..............

Horiz PHF36AD:
Slide: 60/3 .....check
Needle: K4 is at notch 3 (lowest).... manual says 2
Starting Jet: 75....check
Needle Valve: 250.....check
Float level: 18mm
Idle Jet: 62...che? Manual says 65!
Spray Nozzle: 265AB....check
Pickup Pump Jet: 38...che? Manual says 35!
Main Jet: 132...che? Manual says 135!

Vert. PHF36AS:
Slide: 60/3 .....check
Needle: K4 is at notch 3 (lowest).... manual says 2
Starting Jet: 75....check
Needle Valve: 250.....check
Float level: 18mm
Idle Jet: 62...che? Manual says 70!
Spray Nozzle: 265AB....check
Pickup Pump Jet: 38...che? Manual says 35!
Main Jet: 135...che? Manual says 142!

So, I have some discrepancies here!
Also, the slides looks worn where the plastic arm for the diaphragm operates and the chamfer where the idle screw lifts the slide are very worn confirming the little effect of increasing idle speed effectively. most of the idle screws were set to almost all of their travel! I have some new ones laying about. I'm using them.

:oops: I also found the fine gauze screen fuel line banjoes to be with very little crap in them.....

What are your suggestions with respect to the jet sizes?
I await your ideas!

Cheers,
Steve
Author:  graeme [ Mon Apr 07, 2014 7:50 am ]
Post subject:  Re: Aussie TT2 track bike build
Look down the carb with the idle screws wound back the wind them in and see if they are lifting the slides.
Make sure the mixture screws have the small o ring seals and the circuit is clean.
Remove the pump arms from the carb tops they will stuff up things until you get the carbs at their best.
Your not using air cleaners or restricting mufflers so er on the rich side of jets to start with.
Author:  wdietz186 [ Mon Apr 07, 2014 8:22 pm ]
Post subject:  Re: Aussie TT2 track bike build
The jets really aren't off enough to be causing your troubles. 55-65 is in the normal range and low speed riding would be more affected not idle quality/consistency.
Author:  ducadini [ Tue Apr 08, 2014 2:53 am ]
Post subject:  Re: Aussie TT2 track bike build
just switch the two slides, the ramps for the idle screws only are worn on one side.

ciao
ducadini
Author:  618F1 [ Fri Apr 11, 2014 12:53 am ]
Post subject:  Re: Aussie TT2 track bike build
Went away for a while, to come back and find a lot of suggestions. It does seem someone has dinked around with a lot of the components, and some look rather confusing, or at odds with each other. But, some do not matter so much or do not affect the idle and stalling you have. Also, the wear you have found cannot help.

I cannot remember all the specs on the engine, but the jetting you have does seem a bit low for open carbs on a light bike that should accelerate quickly, and Dellorto suggests to start high and work down; say 140 for H and 145 for V? You really should get an assortment of new jets in order, and then you can switch them up and/or down as needed. My F1 manual still shows K2 needles for 36mm carbs.

One final suggestions is, after you have sorted all this out as you think will be a good restart, do not forget to leave 2 or 3mm free play in the cables as they go into the top of the carbs; if too tight you will not be able to lower the idle --- in spite of all the other adjustments you make.

MikeV
Author:  Pantah600 [ Sat Apr 12, 2014 12:56 am ]
Post subject:  Re: Aussie TT2 track bike build
MikeV, Graeme, Ducadini & WD et al,
I'm hearing you and appreciate your recommendations/suggestions.
I'm setting the carbs back to original settings based on 1 of the factory workshop manuals.
I need to set a baseline to start with. MikeV, I agree I need to have a set of other jet sizes to work with and improve the current condition. I understand I should have bigger jets, but I need to start somewhere.
I just happen to have some newish 60/3 slides which I'm going to use. I have cleaned the carbs with compressed air... The idea of swapping the slides is a fantastic suggestion and will work, but the pumper slide groove is heavily worn. I am gathering replacement parts and have got most already. I'm sticking with K4 needles as per the 600 Pantah manual. I have also some K2 as you suggested.
When I have rebuilt the carbs, I'm giving it another go.
Thanks for your ideas. I do appreciate them since I'm the novice here. Wish me luck!
Cheers,
Steve
Author:  D.J [ Sat Apr 12, 2014 3:29 am ]
Post subject:  Re: Aussie TT2 track bike build
The best and cheapest place I found to buy dellorto parts in Australia was here.

http://www.malossistore.com.au/Default.aspx
Author:  Pantah600 [ Sun Jul 20, 2014 7:18 am ]
Post subject:  Re: Aussie TT2 track bike build
:roll: hello my fellow Ducatisti,
One could say I've been flat out working on my carburettors all this time since my last post....but I haven't completely been sleeping too.
So, after waiting a good while for some Dellorto parts to ship in from Italy... And rebuilding the carbs back to stock settings....all good now.
Then, I couldn't get the vacuum settings synchronised.... Also, I noticed the horizontal carb was "spitting" some fuel back out the bell mouth... Hmmmm, maybe the intake valve is cactus?
Well, it isn't quite, but it's not sealing properly. A slight oversight on my part. Hastily wanting the engine rebuild to finish.....
So, head is off and some cutting compound to be applied. Also, the spark plug helicoil is now wanting..... When does this all end?

Keeping you entertained....
Cheers,
Steve
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