GS450 Uprgrades?

[Guest]

Are there any kits available for the 450s that can bore it out? Also, does anyone know where to get rearsets for the S model without spending a fortune? I'm wondering how hard it would be to make rearsets.

Thanks

[hampshirehog]

Nothing available off the shelf that I know of as an upgrade. I'd bet that GS1000 pistons would fit but you would have to measure (and if they fit the Wiseco kits 1085 / 1100 might fit as well - though you would only need half a kit).

These may of course be smaller pistons - I don't know off hand what your bore and stroke is.

Raask do a good range of rear sets that would probably fit. Otherwise have a look at some of the mods guys on here have done with gixxer stuff etc.

[herostar]

You may want to contact GregT about upgrades. I was refered to him by someone else, as he races a 450 down in australia... Here's a message he sent me about possible upgrades to get more power out of our 450's.


Hi herostar,

I'm in New Zealand and build what you'd call Vintage class racebikes so obviously I do a lot of this sort of work. The 450's are a very good starting point - strong bottom end,6 speeds,a good cylinder head and valve train.
It is possible to bore them to take GS500 pistons.I'd recommend deepening the exhaust valve cutaways slightly - say .020in - just for safety. That's if you use standard cams of course.
Bigger cams would need deeper cutaways again.
Cams - a number of US companies have listed cams - I wouldn't go bigger than .410in lift as this will let you retain the standard shim/bucket setup.
Carbs - lose the standad CV's - Mikuni's,Dellortos or Keihins - cable operated slide type carbs will be much better - 34 to 36mm size.
Pipe - look for a 2 into 1 - I don't know what's available in the US but 1 1/2in dia primaries,28in long and about 24 in of 2 in dia pipe before the muffler will work well.
I've finished up using a ported early 400 head - same valve sizes but a smaller chamber - for a little more compression.
There's quite a lot of info on the twins on the GS500 forum too
Hope this helps
Greg

[Macmatic]

What about using a whole GS500 top end?

Edit: But then you have the problem of the ports facing the wrong way.

[boogerboy72]

gr650 head/500 jugs/650 pistons seems to be the way to go.

[Charlie G]

http://www.thegsresources.com/_forum/showthread.php?t=164775

Check out this thread, as it discusses many of the options for moding the 450.

cg

[Nessism]

Sell the 450 and get a bigger GS. It will cost you big bucks to install OS pistons. Cheapest and most efficient thing to do is upgrade the entire bike.

[gearhead13]

Sell the 450 and get a bigger GS. It will cost you big bucks to install OS pistons. Cheapest and most efficient thing to do is upgrade the entire bike.

+1 on that. I spent tons on my 750 and then went with the 1100 totally worth it. Cost me about $2000 for the pistons, bore and machining, parts, new valves etc. Not to mention the headache.

[scottychop]

Link

Don't know if you caught the other thread about motor stuff on the 450...

http://www.thegsresources.com/_forum/showthread.php?t=164775

Scott

[Charlie G]

Don't know if you caught the other thread about motor stuff on the 450...

http://www.thegsresources.com/_forum/showthread.php?t=164775

Scott

There's an echo in here...

cg