I saw this ad months ago but didn't have the time too notice it.
But on the run from the high temps in EmiliaRomagna decided to have à look.
So I ended up in a Church ! in the hills of Toscana to find a modified F3 with 650 engine fitted and 350 included. Marvic17 rear, UPS monster front.
The rear cilinder has the markings MP of MG on the front of the belt part of the cilinder.
I know GioCaMoto made kits 350to550 but does anyone know of the bigger kits ?
Can't take it out of my car 'till end of the week but already looking for info.
Ciao
Ducadini

Hi Ducadini
But did you buy it?
I love F3, very nice bike.
I know about the giocamoto bore kit to 540 for 350 engines. I have it on my race bike.
But I belive it is the top bore kit you can reach for 350.
Regards
Filippo

Ducadini, foto per favore?

Back home after a 14 hour drive .
My wife does NOT like how I go through the Alpine passes in the dark
Didn't take any risks : I had a F3 in the car !

Frame is a f3, some tabs/tubes/support removed so will have to check those dimensions.
Footrests are changed but I still have some frames were the same supports are intact.
Underpart of the fairing is damaged, will have too look for that and the screen.
Tank and fairing painted yellow.
Original 2-1 tubes, but carbon muffler fitted.
Crankcases are 650 items, gearboxshaft 6 spline with 520 and gear moved to the outside. Don't know if it's Original or not.
The rear cilinder has MP in the belt part AND was intended for use on rearward AND forward facing carbs. The upper fin is cut out both front and rear to clear the exhaust port, just like the kits from GioCaMoto.
My guess is a kit with 88 mm pistons
Front cilinder has tabs for oilcooler fitting.
Marvic 4*5 17" rear, Brembo monster front.
Original ( cheap looking) rear shock, UPS monster front.
Pics are on the Phone, will do them later this week.
Anyone know a list with numbers and/or when modifications were made on engine/frame ?

Still not sure how to proceed : go Original or fit special parts.
Anyone know other F3 bikes ?

Sounds cool on the bike!!! But taking your wife on a 14hour drive thru the mountains to pick up an old motorcycle is a recipe for disaster!! You better adjust your strategy or that F3 will be your last bike

Here in the US, I have never seen an F3.....only pictures in books

Clay

Here are a couple of F3's I modified.

both have the 540 kit with 82 mm pistons on a 51mm stroke crank that was used in both the 350 and 400cc F3's

I love those old Oscam wheels! They are so unique. I have a set but have not been able to find the right project, then trying to find rubber. Nice work. Lou

Tnx for posting those pics, general feeling here is to go for the top one.
Me and a friend both drove our 500 Pantahs in 87 or 88 to a dealer in Holland to test two kitted F3 bikes.
Got them for about an hour so we really could get used to the handling.
Although they went a bit faster and picked up better than the Original 350 engine, but nowhere in comparison with our Pantah.
Handling was much better and since we were still young, the crowded position didn't affect anything
Overall the high price and lack of engine made us keep the Pantah.
I hope to do a back to back comparison of F3 and Pantah next year knowing the verdict will be that my wife is going to use the F3 because it's lighter and lower.

ciao
ducadini

Last summer I found a F3 in a church in Toscane. Two brothers had bought the church , with the clausule to restore it, and used it for storage of nice goodies. Some prewar Alfa, Fiat and english stuff standing next to old furniture.
All in the centre of the town, courtesy of a discrete side-entrance .
The F3 has a 650L engine but there was a strange cast-in mark on the rear cylinder.
So now I have a 350 Elefant with a 80 bore --> 513 cc, a 600 SS with a 86 bore -->714 but does anybody know of a kit for the 61.5 stroke 650 ?

And has anybody tried to upgrade (fitter bigger) valves in the 33/30 mm heads of the 350 to make it breath in +500 mode ?
Just pulled the heads of a spare 350 engine (the Original F3 engine) to see what was wrong with it.
I know what's wrong : the vertical cam doesn't turn all the way around so I have to dig deeper . Once that done, I can take measurements to see how much machining is necessary to the heads.
Carlo ? traduzione possibile
ciao
ducadini

Hi Ducadini
Again nice find, and also a nice and unusual set of bored engine: 513, 714 cc.
I know of a 650 engine with 86,4 mm piston of a 900ss , but not about a kit.
But i don't understand if you have those two kind of engines or you're planning to built these two.

Anyway i have to thank you to talk about a 513 engine, this give me the motivation to finally post and talk about mine 513cc Pantah engine , engine that i'have started on this months with the help of a friend. Please check on my tread soon.
Ciao e grazie
Filippo