Big Bore Kit for GS550?

[Twowheeledlife]

I was wanting a little more power out of my 77' GS550 and was wondering if there is a big bore kit for it or if anyone has any tips for a little more muscle. Thanks!

[kdo58]

search

http://www.thegsresources.com/_forum/showthread.php?t=116503&highlight=gs550+big+bore

[almarconi]

Probably cheaper to buy a bigger bike.

Take a look at this build here :


www.thegsresources.com/_forum/showthread.php?t=201784

[tkent02]

Unless you want the lighter, quicker, more nimble handling, and the six speed close ratio transmission of the 550 with the power of a bigger bike.

The 650 top end is the ****. you get 22% to 28% more displacement depending on the bore you choose. A more efficient head design for even more power gains.
More power than the early 750, almost as much as the 850, in the smaller lighter shorter wheelbase 550 frame, all for the price of a used head, pistons and cylinders, and a head and base gasket.
That's a lot of bang for the buck.

[almarconi]

I pointed him to your build thread, hopefully he will get some insight and inspiration from it.

[Magicalzoomer12]

Unless you want the lighter, quicker, more nimble handling, and the six speed close ratio transmission of the 550 with the power of a bigger bike.

The 650 top end is the ****. you get 22% to 28% more displacement depending on the bore you choose. A more efficient head design for even more power gains.
More power than the early 750, almost as much as the 850, in the smaller lighter shorter wheelbase 550 frame, all for the price of a used head, pistons and cylinders, and a head and base gasket.
That's a lot of bang for the buck.

HI,

I was wondering if you are referring to the 650E or the 650L. I have a 1980 Gs550E and want to do the swap. I have my eye on a 1981 650E motor, but was also wondering if the 650L top end, or whole motor would fit in the 1980 GS550 I have. Thanks man!! Amazing Build!

[tkent02]

E, G or L, the top end is the same.

[phydeauxmutt]

I have my eye on a 1981 650E motor, but was also wondering if the 650L top end, or whole motor would fit in the 1980 GS550 I have. Thanks man!! Amazing Build!

E, G or L, the top end is the same.

True, but just to make sure that Magicalzoomer reads it correctly, I will add this:
Tkent said "the top end is the same". Very true, but you asked about the 650L "whole motor" fitting, that will NOT. The 650G and GL (they don't put the G on the side cover for some reason) are shaft-driven bikes. The frames are different, the swingarms are different, there is NO WAY to economically convert your 550 to accept the 650's shaft drive. The 650E, however is chain-driven, but I think the size of the lower end will not allow it to be placed in the 550 frame, so the best thing to do is change the cylinders, pistons and head.