Have been looking around dif places and found a bit of info,but no real definitive answers.

So my question is, if i do my old sportster 1200 up to 1340 whats the best way and or parts to use, and yeah i realize a rebore, pistons and such, just looking for a definitive answer pls

Will be interested in some dif views, yeah money is always a problem but as all ppl who have a harley we can usually find a REAL good reason why we need to spend that money

I'd say for 1340 you would need a kit, from what I've read the biggest you can bore youre 1200 barrels to is 1250, see this page NRHS have 88" and 90" kits for sportsters:

http://www.nrhsperformance.com/ekitsportster.shtml

Thnx for the direction, gives me a few options i hadnt seen before

yo can fit 90 cube barrels if you want but you need to machine the cases..
otherwise 1250 is the biggest you can go without machineing cases but they are new barrells not a rebored 1200 set..
axtell or nrhs.for info parts..

After looking at the site Chops sent me to, ive decided that yeah the gain for the work required isnt worth it, and can do a lot more performance wise without going that far. Any suggestions?

Tell us more about the bike (year etc) and what you want out of it.

all the usuall stuff for any motor comp,heads,intake,exhaust,cams........nothing cheap!!!!!!!!!!!!!!!!!!!!!!
i'm doing a budget build on mine 1200 flat tops s/e heads stg 1 port and clean up 10.5 to 1 comp (s/e h/breather full pipes)already done............
and next year cams,lifters ,adjustable pushrods ,maybe stg 2 heads..(hopefully!)

Bez howdy, i have just punched out my 1994 883 to 1200 and used the following: 10;1 flat top hd pistons, 1200 SE heds, Andrews N4,s SE ignition mod and SE coil the carby is off my 01 Fatboy std cv just because it was newer than the sporty,s 1 it will be jetted accordingly. All this shud be running tomorrow fingers crossed. I did my homework over a long time but like the question of "jesus which fuckin oil do i use?" you will find just as many 883 >1200 recipes of conversion so untill this project is running im still not sure however it does sound good to me. 1 thing i did at the start was to invest in a ref manual which i have read ova an ova

"HD Sportster Handbook" 3rd Edition by Buzz Buzzelli bout $50 from Wheels of Time, This guy will give you many recipes that have been tried and tested ova many years in the states by the best, the kits mostly are from S&S, Zippers, Axtel, Branch Flowmetrics, Wiseco, Carls Speed shop bla bla bla. 1340 u say? well u can get it out to 125.7" by S&S but they say forget it,

Thru out the book he skirts around S/E gear which is where ive gone and a bit cheaper than the others however im tuching $3000.00 so far but pretty well there, now i hope yor hed is starting to hert and thats just the start, lets share the fukin pain, having said all this the more i went for it the people were saying get 2nd hnd 1200 buell heds thats the tckt i found a set at Zippers last week for $179 us clearance stock sale which wud have been perf. I think KC is on the muny tho but just thort u may want sum mor stuff to chew ova. Cheers from that fukin Rat

NO FLAMERS

Yea apologies to the above boyz with my last reply im a bit consumed with my project and am full of it at the mo, dont no if this will help but the above book by Buzz Buzzelli has a whole chapter on "Big Inch Sportsters" and S&S 89" Sidewinder & Superstock kits seem to dominate the pages as well as Truett & Osborne who speacilise in Street rod an Drag racing. Im no wizard  but a 1200 wit cams & ignition and the 42 Mik plus a NOX kit (Pringle Enterprises) wud sit u bak in the saddle wudnt it??? Cheers the rat

Ta Ratz i might just invest in that book, so many options but am thinkin of stayin with my 1200 heads and go the same way you have, and price sounds about the same from the quotes i have been given.