Is this motor really that cool?

[vonyinzer]

Picked up a parts bike for my 81 XS chop project today. Engine number 2FO-11508. I know its a 78, but a buddy of mine who's all goofy about XSs insists that its a "special high comp motor, only made for the 78-79 model years". I've had a few XSs over the years, but haven't run into this particular engine or the story of its apparent awesomeness. Any clues?

Oh, and sorry if this has been gone over. No access to a PC at the moment and searching forums is a PITA on my phone.

Thanks on advance for any help.

-Mike

 

[XSLeo]

I can't say that any bike other than the 750 XS's of I think 72 were other than an ordinary 650 engine.
They built I think it was 200 750 versions of the XS650 so they could race a 750 version of the XS650.
I think that was the only time they made anything other than the stock XS650 engine.
Leo

 

[vonyinzer]

Thanks man. Best info I've found so far is that this particular model had different carbs.

 

[jd750ace]

V78 and 79 had BS38 Mikuni carbs with jetting unique to the model years. Other than that the only thing special on my 79 is where it says special II on the side covers.

 

[gggGary]

yup jus' anudder xs

 

[5twins]

Yes, but it would be nice if your buddy would share what he's smoking with us. If it makes my '78 look bigger and better, pass the bowl my way, lol.

 

[gggGary]

Oh wait 2F0 that means it's Special!

 

[Mikeinnh]

Oh wait 2F0 that means it's Special!

So, is riding it like riding the "special" bus?

 

[Okie]

Yes, but it would be nice if your buddy would share what he's smoking with us. If it makes my '78 look bigger and better, pass the bowl my way, lol.

 

[vonyinzer]

Har har...

Thanks for your help fellas.

 

[jd750ace]

Mine's TOO Special

 

[jd750ace]

So, is riding it like riding the "special" bus?

Yes, ultra short bus. Only seats 2!

 

[jayel]

took a while to find this but I knew I had seen it before....

The 200 bikes with a 750 motor were 1972 models made in July 1971 and the serial numbers were from GS650-102651 thru GS650-102850 as you probably know a standard production 1972 XS2-650 has a serial that starts with S650-xxxxxxx these 200 bikes have GS650-xxxxxx serial numbers.

http://forums.sohc4.net/index.php?topic=45968.0