'79 GS750 Big Bore Kits

[Anonymous]

I have been thinking of getting a big bore kit but before i do that i was wondering how much work is involved with one of these kits? Is this all i need to make it work? Also how many weekends am i looking at here? 2, 3 or longer? I was thinking about the Wiseco 844 kit. I think that would then make my bike drag with my CBR buddies hahaha

Thanks

[SqDancerLynn1]

Time depends?? If the engine has a lot of miles and you want to put big bore kit I would rebore the engine, & don't go overboard on the compression. So it would depend on machine shop where you have your work done. Also you will need to rejet the carbs. More power=more fuel

[Anonymous]

Also you will need to rejet the carbs. More power=more fuel

This is not correct. See the discussion in the other thread about big bores and carb set up.

A larger bore with a slightly raised CR (typical Wiseco kit or similar) does not in and of itself require rejetting.

Lynn, the equation should be "more power = more air/fuel mixture"
More mixture is provided automatically by the increase in swept volume drawing more air and fuel from the carbs. Each stroke of the piston pulls that bit harder, gas velocity through the carb choke is increased, more fuel is drawn out of the carb jets.

Of course if you go really radical, or make other changes at the same time such as filters, then you may well need to make jetting changes. But trust me, if you only fit a Wiseco kit your stock jetting will work fine with an otherwise stock engine.

[Anonymous]

I guess what i am asking is do i actually bore a bigger hole in the engine or do i just replace the piston sleaves? If so i really dont even know anyone in my area except like tool and die shop in my area that would have the tools and/or the experience that would feel comfortable having someone do that to my bike.

[Anonymous]

Yes you would need to bore the block. This is a specialist job, best trusted to a motorcycle specialist, like a bike tuning shop.

[Anonymous]

Thanks for clarifying