Yamaha xs 650 to 750 conversion kit

Question

with the 750 conversion kit, will it still have the 650 reliability, or are there any modifications that will have to be made, to make it as reliable as the 650?

Answer 1

Hi,if you are using a straight over bore kit check the head gasket will seal between the cylinder barrel /head and not overlap into the combustion chamber. You may need to do a plug chop to see how the fuels burning but other than proper tuning it should be ok and prove as reliable as countless other big bore excess`s out there,if it runs lean sort the jets and you will be well away. have fun J.C.  

Answer 2

Rather than  bore it out go cams and carbs. I had a .465 lift Noris cam and 33mm Mukuni carbs and could out run 903's with mine. It was ported and polished. I also put in stock bore Forge True H.C. pistons and did away with the electric start. Ran one car coil to each plug and put  double springs on the  points. It was a 75. You can check it out on www.DIRTYTRICKSRACING.com