TOPIC:

Toddh,

No, only a couple of people on here who have done this mod. One person said his engineering company made special rings to go around the bottom of the sleeves - I would worry about these coming off. The other said no problems. I am a little worried about the new liner skirt thickness but I don't think the liner skirts are a functional part of the bore.

Kwak1261,

I am not sure I know what you mean. Lengthening the con rod and moving the wrist pin up the piston would make no difference to the length of stroke. The stroke is determined by the offset of the crank.

If you lengthen the con-rod it will make the piston sit higher inside the bores at TDC.....thats all.
It would therefore make is sit 10cm higher in the bores at BDC too.

What Todd states about the stroke is true, it would not increase it at all.........but the measurement from centre point of big end to centre point of wrist pin would be 10mm longer if you lengthened the con-rod by 10mm.......obviously.

Personally I dont think you have 10mm extra stroke above TDC on the existing 1300 stroke, meaning the piston would hit the cylinder head & valves BEFORE reaching TDC if you did this ???????

Pete F

Kwak1261 was suggesting that new pistons are made with the wrist pin 10mm higher up the piston body, In effect a longer con rod with shorter piston.

Still no difference to stroke. same stroke with same bore = same capacity.

I don't think there's even 1mm that the piston could come higher in the bore. I've seen 1 and 6 at TDC in the barrels before the head goes back on often enough to know this.

You are all correct, i dont know what i was thinking of, i shall go and re read the Z1000 post again, it made very good sense at the time

street cred going down hill fast

Bad day today!

even struggled with proper motorcycle ring compressors. Got 2, 3, 4 and 5 in from base then found top ring broken on 1.

Couldn't get 6 in from base without risking one of the others coming out so popped the wrist pin and top loaded number 6. Getting the wrist pin back in was a right struggle as can't access the con rod to hold it in the right place.

Some good news though. I found the missing piece of piston ring on the garage floor so I don't have to worry about pulling the bottom end again.

I've ordered a 6 spare sets of rings and a spare head gasket from Japan.

I forgot to mention earlier about the machining. I took a few pages down from the bible which described clearances for oversize pistons and ring end gaps etc. The only dimension the machine shop were interested in was piston to cylinder clearance.