Honda XL 305 big bore kit

[tevie54]

Hi everyone
Does anyone remember the big bore kits for the XL250S back in the eighties, I think there was a 280cc and a 305cc. I have a 305cc kit which features a bored out cylinder with a new liner and obviously a bigger piston, mine is a bit scuffed up and the liner is a bit scored but I think it is salvageable, the problem I'm having is finding out which piston they used. I imagine the kit manufactures used a piston that fitted an 82mm bore and had a 19mm gudgeon pin as I doubt they had them specially made as that would be too expensive.
If anyone remembers these kits or can shed any light on what pistons were used I would be very grateful.
Steve

[tommy]

hi steve thats a very big bore they normally go up to 280 cc kits have a look at je pistons on line they carry a lot of kits for older bikes  tommy

[themoudie]

Aye Steve,

This link looks promising: Xlint_Performance_Honda_XL305_parts

Whilst the above appear to obtain their stock from JE Pistons, JE Pistons no longer hold them as available stock; see link below to JE Pistons.

JE_Pistons_Honda_XR250_pistons

I would also highly recommend 'Eastwood Racing Honda' who also stock Wiseco pistons. At present their website listing of Wiseco products is exhibiting a fault, although I have made them aware of this! However, I have always had good service from Eastwoods and Wiseco pistons that they stock. Here is their 'Contact' page link: Eastwood_Racing_Wiseco_stockists_Contact details

My regards, Bill

[guest2083]

I remember a CB250RS being bored out to 305, so that must have been the same kit. I do note though that on the link it refers to sideport engines so these seem to be for the earlier XL250. THe JE pistons are for radial head engines so again not the same. When I was still working in my old job I spent some of my time looking for a piston that I could use to overbore as RS a bit, I had no luck but I'd not checked everything by the time I left, as it turns out, permanently. One things for sure, nothing where I work now would do it.

[tevie54]

Thanks for the replies chaps,
I think mine must be a mixture of the old 'motorsport' 305 piston and the newer S barrel and by the look of the piston its had some machining work done on it so maybe the combustion chambers were different. I've done some research myself and there was a few companys that did big bore kits for XLs, there's also HAINDST on the underside of the piston which I believe stands for Henry Abe industries.
Henry Abe did big bore kits back in the 70's for bikes like the CB750 so it is possible he had pistons made for his own kits.
Ive managed to locate another piston but no rings so if it's in better condition than mine I might swap my rings over and get a rehone and take it from there.
Any more info would be greatly appreciated.
Steve