Ducati Sporting Club UK > DesmoDue Race Series > DesmoDue - General Questions and Chat > 750ss in Poole - change to 675 ?

[antonye]

FOR SALE
Ducati 750ss 1996, N reg. taxed and new MOT, new fork seals, brake pads, plugs and timing belts, datatagged, Spyball alarm, a lot of bike for the money, £1,300 ono. - , (swadt-2-3562) Tel: (07092) 438125
Price: £1300.00
Town: Looe
Postcode: PL13

[skidlids]

Looe is just west of Plymouth

[Iconic944ss]

Hmmmm interesting differences between the 750 and 600ss...

According to my bible:

Valve timing is exactly the same but carbs are different (but both 38mm)

Tyre sizes are the same 120/60VR17 and 16060VR/17

But seat height is 10mm lower on the 600 (770mm)
overall length 20 mm shorter (2000mm)
but surprisingly the 600 is 20mm WIDER (730mm)

Nasty time however - the 750 is 3Kg, twin discs adding to the weight I guess. Could well be worth a go if considering moving to big bore kit - would it be allowed in the rules??? Personally I cant see why not as its essentially the same bike but worth checking with the M.T. before any purchase I think.

Franko

[skidlids]

Are the cams (Lift & duration) and valves (dia) the same as a 600 is the combustion chamber the same shape or would a 750 give a better squish for a 675CC piston kit, are the inlet and Exhaust ports the same or are they capable of flowing more as they were designed for a bigger capacity engine.
if people are going to convert 750s can I have these questions answered

[Iconic944ss]

Blimey..I thought the valve sizes at least would be in the Haynes but they aint

also - someone has just stated that the 600 barrels will fit straight on the 600 but - both books I have say the stroke is different at 58mm for the 600 and and 61.5 for the 750mm.

[Edited on 12-1-2005 by Iconic944ss]

[skidlids]

Talking to Paynep at Popham last sunday he was saying the 750 bottom end mated with the 583 barrels was the basis for the 620 engine, so maybe fitting a 750 engine with 600 Barrels, stock 600 heads and cams would comply with the rules

[Iconic944ss]

You read my mind Kev and I just did the basic calc...

Std 600cc = 583 actual.

Using the 600 data and putting the 600 barrels on a 750 gives: 618cc

Erm duuno about the big bore kits either - on the std stroke of 58mm, 86mm bore = 673.8cc - unless peeps are just rounding up to 675 !!!

[Iconic944ss]

WOW - Kev - someone has done all the hard work....

Check out this document:

http://www.moto-one.com.au/performan...p2vmodels.html

600/750 - valve durations and lift are identical but sadly the valve sizes are different 33.5 / 30 Versus 41 / 35 for the 750.

Frank

[chicken]

not sure how the rules interpret this.

First line of the rules says - "The motorcycle must be based on an air-cooled 2 Valve Ducati Twin cylinder produced since 1992, displacing no more than 675cc."

You could read this as allowing any 2V bike as long as it is less than 675cc when submitted (ie you could enter a 900SS if you sleeved it down), or that the engine had to be less than 675cc under original spec (ie 750SS would not be allowed, regardless of what is done to the engine).

Since this is basically the engine in the ie models, it makes sense to allow it. Can the powers that be confirm whether this is okay? If it is then anybody that has not got their bike yet, and was planning to get a big-bore kit should definitely look into this option.

[Iconic944ss]

Chi...you rule and summed up my thoughts on this subject suberbly well.

If the frame and engine is essentially the same on the 600 and 750 then why not. The whole aim of the series is to allow accessable racing and IF the basic 750 converted to 675 or 620 does not give an subtantial advantage then it provides another route in.

And maybe means that prices of 600's will not go throught the roof