2 Strokes Down Under

when you run out of oversizes, and if replacement barrels aren't available what do you do?

In another thread mboddy mentioned both 2.5mm oversize - but isn't that over the standard Yam oversizes? If so what pistons do you use?

He also mentioned "NZ Cylinders will double thickness Nickosil plate steel liners for $400NZ each" (I don't fancy the postage on top of that as well)

I've heard of cylinders being re-lined with new steel liners.
Also heard varying comments about whether this really works - anyone got any experience?
Better still anyone know who does this?

Reading the old Phil Irving book (about 50 years old by now!) he states how difficult it can be to get a good bond between ally and iron/steel, is this an issue with re-lining old cylinders?
Has the technique caught up with the necessity? Or is the necessity driving a crap technique?

1) Panic and run around going "arrrrggghhhhh' a lot.

Several things here, yes when ever you have a change in material the boundary between the 2 stops heat transfer, you can mitigate it somewhat but it will always be there. Manufacturers found cast in liners were better at heat transfer than press in liners.

It is simple to reline a cylinder provided the old one presses out. If not the liner has to be cut/machined out and the new liner pressed in.

Last we have Marks plate-over-cast iron solution which is far better idea. You just buy pistons what size is readily available and have them plated to that size. Unfortunately if you have a cast in liner (highly likely) the cost would be around $250-300 to reline that, nicasil is a far better solution, no more rebores just throw new pistons in.

Yamaha only go up to 1mm oversize but after market suppliers go the 2.5mm in .25 steps. Mitaka is one brand sold by almost all retailers.

any more info on this nicasil, sounds interesting if you never have to rebore again, thanks

ken007 wrote:any more info on this nicasil, sounds interesting if you never have to rebore again, thanks

1) Buy piston(s)
2) Send cylinder/pistons away
3) Pay for cyl
4) Pick up cyl from PO
5) Install on bike
6) Ride.

ok, tell me if i have this right, i can buy some standard 64mm pistons for the LC, even though the barrells are bored out to 66mm and they will bring the bore back to standard and i will never have to rebore again? and is that it,, doesnt the stuff wear, im very interested in this, i may have to call them, has anyone ever had it done or have any stories they have heard, ken

no, 1mm thick nikasil is a not safe, it may peel/flake off

but confirm this with a guru.


why dont you just buy some 66mm wiseco pistons?
you can still get them on ebay?

http://www.ebay.com/sch/i.html?_nkw=rz3 ... &_osacat=0

hi, i have the 66mm pistons in place now, its for down the track as its getting close to the bore limits

ok.

get some more 66mm pistons and get it rebored and nikasiled for the 66mm pistons.

then it will be 66mm for ever unless you severely damage the cylinder

thanks for that jeram, thats what i want to hear, its good to have another option than having to eventually track down some fresh barrells, they are only getting more scarce as time goes on and can only go up in price, you still see the odd good set on sale in the UK,i wonder if one day there will be pattern ones?

You will have to rebore again if you sieze the motor of break a piston etc and score the barrel, its not the answer to all your prayers I'm afraid. Nikasil is not cheap but is good about $700-$800 for a twin cylinder. If you damage it again its the same price.

all good, Im just pretty much agreeing with what 2Ti has already said. but Im just picking a piston size for you

these guys already make banshee cylinders which I beleive pretty much fit the RDs

http://www.cpindinc.com/pub/view_produc ... 7258-115SA

think they range from 1000-2000 bucks but make silly amounts of hp

The Banshee cylinders don't fit RD350LC only RZ350.

Just fit one of those 6 transfer port replica OW31 barrels.
$1850 + head + pistons + shipping.

never gave it much thought about these "goodies" ive followed a few peoples builds with the bigger kits but not sure id go down that track myself, id be worried that being tuned to a with in an inch of its life it might be a bit fragile if the slightest thing went wrong, but good luck to anyone who chooses that path, id bet they would be a hoot to ride