[Chuck78]

I thought I'd give a shout out on here for any Suzuki GS550 & 650 owners who don't frequent the GS Resources Forum.

We're putting together a group purchase deal for Wiseco to re-make a small batch of their long out of production 740cc 10.25:1 K740 Suzuki GS650 pistons. Most of the people buying them are adding a GS650 head and cylinders onto a GS550 77-82 crankcase, which requires clearancing the crankcase slightly for the 650 cylinder sleeves, but is otherwise a direct swap. 550 cam gears must be used if using the higher lift shorter duration gs650 cams. The 650 cam sprockets do not work with the 550 crank sprocket.

This purchase is looking to go down in June. Wiseco requires a minimum of 12 pistons, for us, 3 sets, but the cost at the minimum quantity is $125/piston. They told us that 25+ pistons (7 sets= 28 pistons) will get it down to $95-100 per piston/pin/rings/clips, a very reasonable price.

Some of us have NOS Wiseco 65mm gs650 head gaskets, but we are debating getting Cometic to make us a composite 65mm custom gasket run, or gasketstogo.com to make us a custom run of MLS (multi layer steel) head gaskets (the best type, but more money).




If this sounds like something you're interested in, chime in here but go to the GS Resources forum topic and put a word in that you want a set, & when you are able to swing it financially.

Potential Group Purchase - Wiseco GS650 741cc pistons - Page 17

 

[Chuck78]

The GS550-673cc conversion with a stock gs650 head/cylinders/pistons on top of a 77-82 gs550 crankcase has been done by a handful of members over the past several years already, with very awesome results every time.
Tom, one of the buyers, has already got one gs550 swap to the 673cc gs650 top end running, stock pistons. He says that with minor mods, the much lighter gs550/673cc is definitely faster than his stock GS750... the 550 engine is 35 lbs lighter and I believe 2" narrower than the big wide gs750's & gs1000, not to mention 50-65lbs lighter than the monstrous best-vintage-drag-race-engine-ever gs1100e's.

I've been saying for some time now that I think the GS650E (chain drive roller bearing crank version of the gs650g shafty) & GS550+650 top end are the best all around GS models in terms of power to weight ratio, a good rigid frame, nimble & agile handling, etc... not to mention probably the best all around vintage bike of the 70's through early 80's in terms of a classic style standard. Better frames than most anything else of the 70's, lots of good mods available to improve them further as well.

Drop a line soon if interested, or if you discover this much later in the future, the info is there to get another batch of 3 sets or more made for you.