350x cheap big bore kit?

[jkellys]

i've been looking for some info on putting a xr500 sleeve and piston in my 350x motor. the stock sleeve and piston are toast. So if i need to replace these parts i would like to go bigger.but i'd really like to do it on the cheaper side.
so i know that the xr sleeve is longer, and that the cases need to be machined to fit the sleeve. i also know that the 500 piston has a different compression height than the 350.but how much? i read somewhere that you need to run a spacer to get the piston down in the hole. but how thick, where does it go , under the jug, between the head and jug? I don't know. will the cam chain work? people have done this but the info i found was kinda in complete.

any help would be appreciated

[big_daddy124]

i need some info on this also! how about a xl 600 or xr?

[SWIGIN]

check out my ascot head swap thread in the mad scientist section

[jkellys]

yeah i read some of the thread, that's a pretty involved swap that you did. in your motor you used the stroker crank, right? i'm wanting to use the stock stroke crank,only because it doesn't cost anything.

[SWIGIN]

the same rules apply.....you need a shorter rod or a spacer like you said.

i dont think with a spacer the cam chain will be long enough

[jkellys]

so does anybody make a custom piston for this setup?or is their a shorter length rod that will work? or is their no such thing as a cheap big bore kit?

[SWIGIN]

cheapest you'll find is how i did it with all off the shelf replacement parts.....custom parts are big money.

the price of cool aint cheap

[The Goat]

cheapest you'll find is about 500 bucks using LA sleeve...

not sure how much yours runs swigin...but that whole rod shortening thing isn't cheap from what I've been quoted.

If you can find a freakishly old stretched cam chain you might be able to get by with that.

[greenhuman]

From what I can remember I had my 350X rod shortened an extra 3mm for the 500 Ascot big bore kit and stroker. For the standard crank you could run a 1 1/2mm spacer and take 1 1/2 mm off the the top of the piston. An old stretched chain would probably fit with this size spacer.

[SWIGIN]

[QUOTE=The Goat;733431]cheapest you'll find is about 500 bucks using LA sleeve..
swigin...but that whole rod shortening thing isn't cheap from what I've been quoted.
not sure how much yours runIf you can find a freakishly old stretched cam chain you might be able to get by with that.[/QUOs



i'll have about $500 in it with the stroker crank...to just get a rod shortened has to be cheaper then the whole crank but i never looked into it.

it helps price to do most of the machining yourself as well.

but like greenhuman said in his post, thats one way i thought of doing it but i figured since my rod is getting shotened i might as well just get it shrunk to the right size and be done.

[jkellys]

ya i guess if you are spending the money, might aswell just buy the stroker crank. does powroll charge you extra for shrinking the rod? do you use the xr 500 base and head gasket?

[SWIGIN]

ya i guess if you are spending the money, might aswell just buy the stroker crank. does powroll charge you extra for shrinking the rod? do you use the xr 500 base and head gasket?

same price for the rod and you use 350x gaskets with the hole cut bigger for the cly and combustion chamber.