Monroe Federal Savings & Loan Association

Initial Business Response /* (1000, 13, 2015/02/24) */
The cylinder & piston in question is still at our shopI checked with ***, the supplier of the parts to verify the required finished size of the cylinderThey told me it should be 89MM which is the size in their catalogueThe cylinder is
89MM now, not 1MM larger than requiredThe piston is appx1MM smaller now than when it was manufacturedThis piston was severely overheated due to high combustion temperatures as a result of a lean fuel condition
The kit Mr *** supplied was an overbore kit with a very high compression ratioThe size of the cylinder was increased from 400cc to 440cc and the compression ratio was increased from 9.5:to 12.5:Making these changes to an engine would require changes to the fuel system and fuel with an octane rating much higher than available at any service stationMr *** may not have been aware of this as *** does not put any warnings in the packaged product
If Mr *** wanted to fix his cylinder and purchased another kit, we would supply the labour to install & fit the sleeve at no cost as a good will gestureI would suggest that the replacement kit should have less compression than the first kit he supplied
The link below is a website that has information on this engine and these issues
***