xs650dreamer
XS650 Junkie
76MM
KZ 1000: 6 mm oversize
2.992 In
DRAG
12.5:1
MTC-K1197H
~kop
with these pistons were talking about here the compression wouldnt be so high with the xs head would it ?
76MM
KZ 1000: 6 mm oversize
2.992 In
DRAG
12.5:1
MTC-K1197H
~kop
So I take apart a XS650 crank and find this . The one with the slugs in it is the early "256" crank from about '72 an '81 is on the left for comparison . I guess I don't know everything about these engines . The crank shows no evidence of having been apart before . New one on me .
~kop
Hi Jack, im new here and reserching for a big bore, LR, rephased, Flat track project, are the CR500 rods (depending on manufacturer) tough enough for my aplication or is Carrillo the wise choice . imlooking for hopefully a slipper piston won 10.5 to 11. to 1 compresion, is this possible in your opinion?Those GSXR pistons won't work period, not enough dome volume to reduce combustion chamber volume from 63CCs to around 45 to 40 CCs, you would need to weld up the chambers and re-work the shrouding of the valves to compensate for flow loses in the 300 to 400 lift range. The XS intakes ports REALLY RESPOND WELL to volume reductions by raising the floor 2mms and laying the short turn back and in doing so really takes some dedication,ability to weld or either lay down really good epoxy,opening up the spigot area is the real key though,then going back to rework the roof section to alter flow through out the the lift range. Small ports= bigger gains in velocity with minimal loses of flow in certain lifts, that you'd never feel in the pants.
For pistons using the CR500 long rod,you need to start looking at the Kawasaki900/1000 pistons using the later style J Head, 18mm PISTON PIN, about the same weight as stock XS piston, maybe lighter after mods. Its the best piston option that I can think of other than going custom.
From Tech... Have a read here.This is very interesting but the whole long concept is more of theroy but has any body here actually done this?
Hi Sig. have you had good luck with this kit , what was the claw breakage?Yes I have a long rod engine. Did not use CR500 rods used the kit that 650 Central made and sold.
The 650 central kit uses KX 500 rods and custom pistons.
Rephasing with the KX rods caused some problems initially with selector claw breakages apart from that it went very well.