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For Sale - 1972 Yamaha GS650 (XS650 w/factory 750cc engine)
- Thread starter Virginia404
- Start date
Ok Scob.
I'm going to try this one last time.
You can indeed advertise your 427 corvette as a 454 corvette if indeed the engine in it is now a 454. If that is the case it would be incorrect to advertise it as a 427 since it is no longer a 427.
You could NOT legitimately advertise it as a FACTORY 454 corvette.
As for the GS650....
The GS650 was a FACTORY by Yamaha special edition. It was created to allow yamaha to use the 750 engine in their race bike. The rules specified that a certain number of bikes had to be sold to the general public to qualify as a production bike for the classification they were competing in. They did not care about badging and it was not created for mass sales. It was a very limited number that were built and sold for the sole purpose of qualifying the motor for competition. It based on the xs650 as that was the bike they had been competing with and was the next logical step in the evolution of the racing program. They did this with the least amount of addtional costs as possible. Others here can correct my errors but that is the basics of the bike's creation as I understand it.
As for the stock front tire you are continually rambling on about... the stock front tire is more than adequate for a 100cc upgrade as long as the rubber is good.
The GS650 will look like an XS650. I may be incorrect but I don't think they even used big fins on the conversion. The numbers tell the story.
I'm going to try this one last time.
You can indeed advertise your 427 corvette as a 454 corvette if indeed the engine in it is now a 454. If that is the case it would be incorrect to advertise it as a 427 since it is no longer a 427.
You could NOT legitimately advertise it as a FACTORY 454 corvette.
As for the GS650....
The GS650 was a FACTORY by Yamaha special edition. It was created to allow yamaha to use the 750 engine in their race bike. The rules specified that a certain number of bikes had to be sold to the general public to qualify as a production bike for the classification they were competing in. They did not care about badging and it was not created for mass sales. It was a very limited number that were built and sold for the sole purpose of qualifying the motor for competition. It based on the xs650 as that was the bike they had been competing with and was the next logical step in the evolution of the racing program. They did this with the least amount of addtional costs as possible. Others here can correct my errors but that is the basics of the bike's creation as I understand it.
As for the stock front tire you are continually rambling on about... the stock front tire is more than adequate for a 100cc upgrade as long as the rubber is good.
The GS650 will look like an XS650. I may be incorrect but I don't think they even used big fins on the conversion. The numbers tell the story.
Honestly, this has been explained more than it needs to. Does your title say GS650? Is your vin stamped GS650? If not, then you just have a clean, low mileage bike and that's where the conversation ends. If it does, then you have a rare bike and can possibly make some money. Again, you can contact Yamaha and I'm sure they'd be happy to tell you what your bike is. Also, your front tire doesn't care about the horsepower or if the bike is 750cc or 75,000cc, the speed ratings are independent of engine capacity.
The bike has been around for awhile i see,
It says elsewhere they just installed 750 big-bore sleeves in stock castings, The rest of the motorcycle is exactly as any other 1972 XS2 650 motorcycle.
Is there a picture of the stamped in 743cc on the cylinders?
The thickness of a 650 sleeve is .120 inches
So pop the 650 sleeve out, (good luck)
then pop in the 750 sleeve which fits in the housing the same as the 650 sleeve.
The sleeve cylinder thickness would end up being .06 .05 probably well out of spec. to be a safe everyday rider.
If the housing was made bigger you only have .31 inches to play with before going into one of the studs.
It says elsewhere they just installed 750 big-bore sleeves in stock castings, The rest of the motorcycle is exactly as any other 1972 XS2 650 motorcycle.
Is there a picture of the stamped in 743cc on the cylinders?
The thickness of a 650 sleeve is .120 inches
So pop the 650 sleeve out, (good luck)
then pop in the 750 sleeve which fits in the housing the same as the 650 sleeve.
The sleeve cylinder thickness would end up being .06 .05 probably well out of spec. to be a safe everyday rider.
If the housing was made bigger you only have .31 inches to play with before going into one of the studs.
Im thinking about it from a technical stand point, not by hear say or a repeated story.
Follow the science right? The micrometer reads the 650 cylinder walls at .120 inches thick.
Reduce that thickness to size the 750 pistons since they claim is the stock casing wasnt modified.
What would be left,... about .05 .06 maybe .07 sleeve wall thickness. Maybe the numbers would show the sleeve wall thickness much smaller?
I havent looked up the diameter differences of the cylinder diameters
Wouldnt it get extremely hot then crack ?
Follow the science right? The micrometer reads the 650 cylinder walls at .120 inches thick.
Reduce that thickness to size the 750 pistons since they claim is the stock casing wasnt modified.
What would be left,... about .05 .06 maybe .07 sleeve wall thickness. Maybe the numbers would show the sleeve wall thickness much smaller?
I havent looked up the diameter differences of the cylinder diameters
Wouldnt it get extremely hot then crack ?
.,.
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Clymer yamaha service repair book show the 650 sleeve can be bored 4 times over to 1.0mm
Im finding the pistons rings for the std tx750 pistons to be 80mm
Inside diameter of the 650 sleeve is 75mm
80 mm too big to go in a 72 cylinder casting.
Im finding the pistons rings for the std tx750 pistons to be 80mm
Inside diameter of the 650 sleeve is 75mm
80 mm too big to go in a 72 cylinder casting.
Pictures of the stamped 743cc cylinder would clear it up, due you have a picture of that?
What does the title say, maybe a picture of that too.
A lack of pictures, pictures of the frame neck sticker and a picture of the 743cc stamped cylinders would end the debate.
if the title says s650 xxxxxxxx vin but the bike is stamped GS650 xxxxxxx wouldnt the DMV give you some grief?
the outside diameter of a 650 sleeve about 79-80 mm without measuring
if the tx750 rings for std size pistons are at 80mm
What does the title say, maybe a picture of that too.
A lack of pictures, pictures of the frame neck sticker and a picture of the 743cc stamped cylinders would end the debate.
if the title says s650 xxxxxxxx vin but the bike is stamped GS650 xxxxxxx wouldnt the DMV give you some grief?
the outside diameter of a 650 sleeve about 79-80 mm without measuring
if the tx750 rings for std size pistons are at 80mm
I posted a Quote of the post TZ750 posted with Verified yamaha information about his GS650/750 Factory XS2...........
I have posted the re-bore sizes and these pistons, .5mm oversize to 2mm oversize, can be bought from Criuzinimage. They also have the 706cc bigbore 78mm pistons that will go into standard XS650 sleeves.
If you don't want to believe his information then i cant help you with anything else
All this time spent using a micrometer would be better spent looking at your title and vin and then giving us the answer of what bike you have. I don't know what you're trying to prove at this point. This isn't some government conspiracy to pull a fast one on you. They can and do bore stock cylinders up to a point as skull mentioned. They can and do sell 750cc sleeves for stock cylinders. This isn't scientific theory. These products exist, and are in use, right now. I gotta bow out of this, as I see there is no getting you to listen to logic. Good luck on this witch hunt, I hope you find whatever it us you're looking for.
LOL
There is no debate Scob.
Just been a handful of members trying to help you wrap your head around reality.
Some of your statements make it appear that you are more interested in trolling, preferring contradiction and wandering down the path of idiocy. Follow the science???
First you would need to understand the science.
These parts exist. These oversizes are available.
They are not theoretical. They are in use. Probably by the thousands. I personally have a set of 750 barrels in stock cylinders. I also have a set of 750 barrels in an aftermarket big fin kit.
Nobody need to produce pictures to prove anything to you. Look at the numbers on your OWN bike. That is all you need to know.
I'll reply no more to your ridiculousness.
My 10 year old nephew has a better understanding of engines than you are presenting. It seems to me your "persona" is intentional and you are not actually seeking any answers, which have been spoon fed to you numerous times by numerous members.
Have a nice day and good luck.
Ive done over $20,000 of business here on xs650.com, mostly with Mark Tomlinson. Ive spent a lot of time discussing motor building with Mark.
Dont accuse me of trollingso your point is to insult me?
Can you post a picture of the 743cc stamped in the cylinders, whats so hard about that?
Or draw me a picture, Ive spent an hour drawing this one BECAUSE IM ASKING QUESTIONS, Dont answer with insults.
Explain how a 750 sleeve works in the same hole a 650 sleeve works
3 mm is on the top of the sleeve with the lip, so the sleeve wall would be what? 1mm thick ?
Dont accuse me of trollingso your point is to insult me?
Can you post a picture of the 743cc stamped in the cylinders, whats so hard about that?
Or draw me a picture, Ive spent an hour drawing this one BECAUSE IM ASKING QUESTIONS, Dont answer with insults.
Explain how a 750 sleeve works in the same hole a 650 sleeve works
3 mm is on the top of the sleeve with the lip, so the sleeve wall would be what? 1mm thick ?
The hole in the crankcases where the liner slips in is about 86mm ID... so any liner less than that will slip in without moddin' the cases. I just checked a big bore jug.... the OD of the liners is 85mm. the liner wall is 2.5mm.... that gives us an 80mm bore... which give us our 743cc (750) engine. It's all pretty simple really. I'm guessin' the makers of my big bore jugs didn't reinvent the wheel, they did what Yamaha did with the GS650.
Just an observation here..... this is a For Sale thread. You've burned up the last two pages questioning the existence of a GS (it does).... questioning the science and engineering behind it (it's solid in that it's been around 40+yrs).... questioning whether or not Yamaha can call it a 750 (they can).... Questioned why your bike wasn't as valuable as this one (it's not a 1 of 200 production run, so....)
In short, you did indeed exhibit trollish behavior, whether that was your internet or not.... and thoroughly dirtied up a For Sale thread in the process.
I think we all would have been better off if you'd started a different thread asking these questions.
Just my
Just an observation here..... this is a For Sale thread. You've burned up the last two pages questioning the existence of a GS (it does).... questioning the science and engineering behind it (it's solid in that it's been around 40+yrs).... questioning whether or not Yamaha can call it a 750 (they can).... Questioned why your bike wasn't as valuable as this one (it's not a 1 of 200 production run, so....)
In short, you did indeed exhibit trollish behavior, whether that was your internet or not.... and thoroughly dirtied up a For Sale thread in the process.
I think we all would have been better off if you'd started a different thread asking these questions.
Just my
The picture of the paperwork I saw says "Manufacturer of Origin" with joyridemotors las vegas nevada on it.
I think Mr Bowlingcc was the guy sharing that picture. It wasnt for this bike it was for a bike he bought.
With the gs650 vin and it also says the bike weights 417 pounds. My CLYMER manual states the bike weights 427 pounds. And it has the mileage, but its not a state issued title, its a 'Manufacturer of Origin" with A location in Japan also on the document, Im trying to find that picture again.
My Chinese quad came with a Manufacturer of origin document too, DMV wouldnt issue me a title cause its not street legal and said the Manufacturer of Origin is my proof of ownership.
I think Mr Bowlingcc was the guy sharing that picture. It wasnt for this bike it was for a bike he bought.
With the gs650 vin and it also says the bike weights 417 pounds. My CLYMER manual states the bike weights 427 pounds. And it has the mileage, but its not a state issued title, its a 'Manufacturer of Origin" with A location in Japan also on the document, Im trying to find that picture again.
My Chinese quad came with a Manufacturer of origin document too, DMV wouldnt issue me a title cause its not street legal and said the Manufacturer of Origin is my proof of ownership.
