SUZUKI GS camshafts values....

[Guest]

Hey all
I am looking for some ways of increasing power of my 673cc swap on my suzuki gs 550...
Ok, so I assume that a classic, best way to get more HP would be to replace OEM pistons by the famous K740 Kit from Wiseco... still very hard to get...

Sooo while I am looking for the piston kit, I would like to have a look on the suzuki gs camshafts...
- I think I have to keep the gs 550 sprockets, but I can without effort, mill the sprockets to make them adjustable... and to help them to be able to assemble them to every camshaft I can find....
So I consider that if I need to mill something this is not an issue. Starting from this, I have now, GS 550 camshafts. Could someone answer to this post with other suzuki gs camshafts specifications ( lift and duration)? I am thinking about GS 850, GS 1000 ones.....

thanks a lot!

[Steve]

I can’t offer any specs without consulting a manual, but I CAN tell you that cams from anything larger than a 750 are simply too long to fit.

Exactly how much more power are you looking for? I have heard that the 653 swap adds about 50%, but you can always fall back on the drag racers’ philosophy: “There is no replacement for displacement.”

.

[Old Colt]

The 550 and 650 might be considered a "small block" where the 750 on up are larger such that there is little interchangeability.
That said I have always run the 750 clutch assembly in my '79 550 which adds one more plate.
Camshafts, the 650 has a milder grind than the 550 so for performance the 550 are a better choice. Around town the 650 cams might be right for some people.
My experience dating back to when these bikes were new, once I had ported the head and installed a set of smoothbores the bike absolutely came alive. Mid range power was good but interestingly the bike pulled hard right up to 12,500 and a touch over. I still had stock valve springs which I expect was my true rev limiter. I raced the bike and the engine spent allot of time at that limit with no issues. I was always scared at Daytona on the banking where the bike sat at 127mph on the limit for what felt like minutes at a time. Never turned out to be an issue.
For street use I doubt there is allot of value in aftermarket cams, the bike can present itself quite well still and I like others look forward to getting the bigger bore setup into it.
One thing I am not sure about and others can answer, are the later emissions cams here in the US at least a different grind?
I rode the BS carbed bikes and I could not tell since mine was quite lively by the time they came out.

[boris.h]

even with other brand camshafts maybe....? kawa....for example...

[eddypeck]

I'd say its highly unlikely a camshaft from any other bike, especially from another manufacturer would fit, they'll be made for the specific engine configuration and even if the dimensions were similar the clamps would be in whatever location was convenient for the oil apertures of that particular engine etc.

Even from different years of the same model things like that get changed as the engineers evolve and improve the design.

As mentioned, different countries might be an option, I'm in the UK and over here we know not to bother with French imports are they're usually de-tuned to meet their restrictions. In modern bikes that's often just ECUs now but in older stuff carbs, jets etc. but I don't know if that ever goes as far as cams and for your specific needs I have no idea.

I notice from you're profile it says you're south of France so maybe looking at UK eBay might get you some better performing parts.

Ultimately if the bike you have doesn't have enough performance for you then surely it makes sense to get a better bike? Especially as it's a small engine bike you're starting with.

The other attentive I've seen done, but I expect it would be expensive, and I'd no idea how you go about finding someone to do it would be to get your cam re-profiled. Obviously taking away material is easy, but I've seen it where the lobes are literally welded to add additional material so they can then be reground to the required spec.

[GregT]

Pretty sure the question of the best 550/650 cams has come up before - try searching 650 cams.
From memory the best are 650M katana cams - but not by a great deal.
You'll actually get good results by dialling the standard cams in - I'd try 107/108 lobe centers.

Where new blanks are not available, cams are built up using a Eutectic overlay - which lasts very well indeed.