500 into 450 frame

[alleyrat]

Anyone know if a 500 engine will bolt directly onto a 450 frame

[LeeGS550E]

Do a search - looks like there's lots of previous discussion about this. For example: http://www.thegsresources.com/_forum...00+engine+swap It appears your 450 shares enough DNA from the 500 that you can swap some parts and bore it out. But I'm just parroting what I found by searching old posts - that's where I'd suggest you go.

[Mekanix]

So your giving up on your engine ? I still want to see a pic of the damage!

The answer is Yes it will fit.

The bottom end is identical (1980 on) I actually have only ever found one difference and that is the GS500E model has a sump pan with the connections for an oil cooler, there may be something in the case but i haven't seen a torn down 500e case yet. Besides that the basic bottom end is the same. So even if you got the 500 engine base you could swap your top end onto it and get going again in the shortest amount of time.

The top end is the only real difference.

You will have a problem with the exhaust pointing straight forward instead of out to the side so you will have to fabricate an exhaust if you want to use the 500 as it is.

You will need the carbs for the 500 or you can try jetting the 450, It shouldn't be hard but again less work with the 500 parts.

Besides that it should be straight forward although keep in mind the head on the 500 is a little bulkier so it might be harder sliding it into the frame.

There are people using the 500 engine with the 450 head for more compression although the place this has been discussed in more detail is on the GStwin forum as a race bike setup.

http://gstwins.com/gsboard/index.php?topic=57916.0

http://www.thegsresources.com/_forum/showthread.php?t=170287

http://www.thegsresources.com/_forum/showthread.php?t=175330

[alleyrat]

So I looked at the link you gave me and I just had a few more questions

So if I get a 500 motor mounting it in the 450 frame then put the 450 heads on bored to the 500 piston and used the 450 head it would work?

[alleyrat]

The engine is toast....at least the case is....I'm having a hard time finding a 450 locally...but some people have told me that there may be some 500 engines available so I'm just trying to get all my options

[Mekanix]

Yeah it should work just like that. There are a few things that you have to do to make sure there is enough valve to piston clearance. Do the static compression ratio calculations and adjust If necessary.

The 500's base gasket is half the thickness of the 450's So that gives you something to adjust with.

You could use the 500's jugs or bore yours to the 500's size.
the gstwin site has all that info worked out.


your quickest option is to use the 500 base with the 450 block and head if you dont want to mess with anything else.

[LeeGS550E]

The engine is toast....at least the case is....I'm having a hard time finding a 450 locally...but some people have told me that there may be some 500 engines available so I'm just trying to get all my options

I have a 450 sitting in my backyard. Was planning on taking it to the dump. Its just the engine and frame. Let me know if you want to figure something out. Would love to see it go to a good home (or even a bad home).

[alleyrat]

Just got a engine with only 3400 miles on it...needs a good cleaning and a few gaskets and such but for $500 delivered to my door....all and all I think it was a good deal...hope UPS doesn't mess it up