ducar 125 rebore and piston help.

[nahoo7]

hi all,
I replaced the piston and rings in my sons 125cc ducar went well for a couple of days then unfortunateley was blowing smoke and lost compression.
So I stripped the top end again and found that a piston clip had come out and gauged the bore and wrecked the piston.
Can I rebore the barrel and if so can i get a bigger piston for this engine many thanks nahoo7

 

[Le|Garage]

yeah you can get a bigger piston for that. You can go up to 56mm. try Akunar Motorcycle Parts & Accessories Thailand should set you back abour 40 bux...then bore it to suit the new piston. Remember to bring in your old piston to the machine shop too so that they know the piston to wall clearence. cheers

 

[nahoo7]

okay thanks very much for the quick reply.

 

[themountain]

You can go up to 57mm...my neighbor got a 57mm TB piston for 8months now and the engine still rocks!!

 

[nahoo7]

where did he get the piston from? I emailed akunar parts but they dont stock parts for the ducar.they need measurements to see if they may have something but I am not sure what measurements they need.

 

[Cactus Jack]

where did he get the piston from? I emailed akunar parts but they dont stock parts for the ducar.they need measurements to see if they may have something but I am not sure what measurements they need.

They'd need the gudgeon pin diameter and the pin height (from the top of the pin bore to outer edge of the piston crown)

Sometimes you can find a decent Honda shop who'll measure your piston and find a Honda piston that'll work , but these days there's too many uncooperative wankers who know JS about SFA working behind the counters ........

Anyway , here's the Akunar site with info on how to measure pistons . When buying different pistons you have to check the depth of the valve pocket cuts , dome height and overall skirt length . On stroked motors you have to make sure that the bottom of the skirt can't hit the crank weights . Basically ALL measurements have to be the same distance from the pin bore as the stocker (except the diameter) . Any other changes will need to be carefully checked for clearance .

Piston Dimensions Akunar Motorcycle Parts & Accessories

 

[Hillz]

yeah China pistons most times match up to something japanese, i do it for bike shops everyday...