Asking help from the experts: GS500 mill in a GS450??

[Sideshow]

Hey all,

I've been hovering this board for a while.  So as much as my minute single post so far belittles me, I'm going to ask this.  I've turned my old 450e into a pretty mean cafe racer, but the engine is getting tired.  I could put money into the valvletrain or try to do more mods to keep the performance level up.

OR!  I could bolt in a salvage gs500 engine.  BUT, I'm not 100% sure the bolt in job is as easy as I hope it to be.   Does anyone know if the 500 twin bolts into a 450's place?  This could be the sleeper I've been wanting the 450e to be!

[Gisser]

Sorry, no.  The GS500's exhaust ports exit straight ahead.  Right where the GS450 locates its frame tubes.  Of course, where there's a will, there's a way.  Just not a way that is a bolt on proposition.

[yamahonkawazuki]

could he modify the frame tubes to clear exhaust manifold?

[Sideshow]

You rule!  I never noticed that.  Well, I do have a will, as well as a welder and some chromoly tube and access to a tube bender.  Yes, I have a will for sure.  But if anyone knows anything else, I'd love to know.

Also, are the electrics as simple as they are on the 450?  I mean, I have a 4-prong connector off of the voltage pickup and then the power to the starter.  The coils are seperate for spark, so it's not difficult in case I screw them up backwards. . .

[JamesG]

It would be easier (and probabaly cheaper) to punch out the 450 cylinder (or find an old GS550 top end?) freshen up the head with a vavle job and maybe some porting.

[Pkaaso]

Hey guys this may not relate but, here's what I'm doing today.

I have a 99 that needs a motor. The problem is the guy who owns the bike has lost the subframe piece.  I found another subframe off of a 93' but the bolt holes in the frame and the cross member your talking about, doesn't match up. It miss-aligns by about 1/4".  My welder is going to cut off the piece on the bike, bolt it to the subframe and re-weld to the frame.

My thought are: If this can be done, it should be no problem to cut off both ends of the cross piece and reweld in a position that will allow the exhaust to be installed.

Go for it!  I want to hear how it turns out.

Paul

[Pkaaso]

By-the-way... The welder is charging me $30 to cut and weld this for me.  I think this is a universal price.

Paul

[The Buddha]

Not just the cross piece Pkasso, the down tubes will get in the way.
Cool.
Srinath.

[Sideshow]

James,

It might be cheaper, but it's the time factor.  I love working on my bike, don't get me wrong (if you saw it, you'd understand).  But to think of all the time I could put in the carbs and the top end versus a 2 hour swap-n-go that the 500 engine would be without any mods was a good plan.  I think my skills would be good enough to mod the frame well enough to make this work and with less time and money than the punch-n-port 450 job.  I actually don't know where I'd even start finding parts for a punched 450 project either.

A 550 is a quad, isn't it?  I could put a 500 top end on my 450 bottom, too, I guess.  But where do I get a 500 top end in good shape without having to buy an attached bottom end???

[Pam G]

You might also subscribing to the gstwin email list at www.micapeak.com.
There are a few more people over there that have (and race) 450's, as well as a few other guru's.

I doubt that the GS500 motor has that much more hp than the 450, if that's what you're thinking also.  Not sure if that info is at www.gsresources.com.

If you do switch to a GS500 motor you will probably need GS500 carbs.  The 450 carbs are not the same as the 500.

[Pkaaso]

Not just the cross piece Pkasso, the down tubes will get in the way.
Cool.
Srinath.

Oh!  That would have been sweet.  Thanks Srinath.

[werase643]

Hey cheezehead.....
I gots what you need!!!!!

I have a  complete GS400 head!!!! from europe/japan with a 8 valve head and the exhaust ports go out to the side.....this requires some research with KZ1000 or FJ1200 pistons to work...this would work so much better for you than me

my option is to weld the exhaust shut and re cut it to exit straight out like a 500

you can install 500 pistons in a 450....2-3 mm bore increase... i think

cutting and welding a stressed member(cradle) of a frame takes some thinking/measuring/thinking/measuring/thinking/measuring/cutting/welding/swearing/grinding/welding....and it's done


ex-cheezehead

email me at werase643@msn.com and i'll send you some pics of the head/cylinder