the best 650 engine options

[Rob S.]

I once installed such an extreme cam in my CB350 that the inside of the cam cover had to be ground down.

[timebombprod]

I once installed such an extreme cam in my CB350 that the inside of the cam cover had to be ground down.

i wish there was an actual performance cam for the 650, i guess i should be happy that theres atleast a bore kit for my specific bike.

ive been told by a madman that i can make my bike an 840cc but he said prepare for it to blow up always, so i stuck with the bore kit lol. -

[650Skull]

Where are the 740 pistons coming from.

I have a couple of threads on the 740 big-bore kit. One is a good right up from a 550 changing the barrels and head from a 650 and installing 740 oversized pistons in it. Think they are Wisco pistons as there was a wip around and they got a min made from wisco. Think it was 12 pistons min.

Link to the group buy on the 740cc pistons............sub link inside

https://www.thegsresources.com/_forum/showthread.php?244769-Which-65mm-pistons-for-a-big-bore&highlight=GS650

https://www.thegsresources.com/_forum/showthread.php?243343-GS550T-to-740-build-(aka-the-shaniqua-project)

May get something from this 550 to 672cc

https://www.thegsresources.com/_forum/showthread.php?84029-Suzuki-GS-6-550-Yes-672-block-and-pistons-on-a-550-cases

550 to 740 via 650 head and barrels..............Note GS750 high dome pistons were used and wasn't sucesfull
https://www.thegsresources.com/_foru...fficially-Done!

https://www.thegsresources.com/_forum/showthread.php?237434-I-have-a-1978-gs550e-where-can-I-get-performance-parts-what-should-I-do/page2&highlight=GS650E

Another link

https://www.thegsresources.com/_forum/showthread.php?201268-GS550-to-650-cylinders-questions-compression-heads-vm-vs-bs

Member GregT has had a lot to do with these GS650's and seems to know his stuff.

[timebombprod]

https://www.cruzinimage.net/2018/12/18/81-83-suzuki-gs650-740cc-bigbore-pistons-kit-65mm-piston/

This is the kit I'd be getting, I spoke to a guy that had a shop install the kit for him and he said it runs great with the installation and that the shop was surprised of the quality for the price the kit is.

If I could get a set of 4 wiseco 65mm pistons I might go that route but I have a feeling that this kit is inexpensive as the 650 isn't a common GS and the kit probably sold like crap overtime, it's possibly the same reason I got an exhaust for under 300 that was originally closer to 500 when new.

[Nessism]

Wasn't there some threads here reporting the cruzinimage BB kit didn't fit?

Regarding things like cam timing and lift, that info is in the factory service manuals for the bikes. You might want to download both so you can compare things like this.

Edit: thread about bad pistons...https://www.thegsresources.com/_foru...stons-hit-head

[timebombprod]

I did see that thread about them not fitting, but I also spoke with a guy who had a mechanic shop install the same kit on his 650 and it ran perfectly fine, so we will see what happens