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Discussion Starter #1
I'm thinking about boring out my 750. What is the safest to bore it out to? I want to take out the airbox and put on a set of after market pipes when I do this too.
 

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^ I got that ;),you are cold man,cold:)
He did mention three of the deadly sins,touching the stock intake,aftermarket exhaust and God help us all, Modifying a Stock engine,I sure am glad he doesn't want an aftermarket seat.

I sense a rant/tirade coming.I am so in tune with this board,I must be psychotic,,errrr, psychic!

And I must add an "Oh no,you didn't" right about here also.
 

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Giggity!
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One thing I will say in the act of boring out a 750's engine. You'll have to go find parts. There's no kits for this bike to do that.

It could end up being quite a pricey little project.
 

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Vulcan 750 pistons come in two oversizes. They are for repairing a worn engine. You would not gain enough displacement to make any difference powerwise.

I had aftermarket pipes, with a properly jetted stock intake. Sounded great around but were awful out on the highway at 75-80 mph. Went back to stock, lost a lot of money.

Use non stock air filters at your own risk.
 

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Sorry, but it sounds like more trouble than it is worth to me.
I do recall a member who said his engine was rebuilt with pistons from an 850 Suzuki.
I tried to find a piston that was close enough in size to work, but I couldn`t find one.

If you want a bigger bike, buy a bigger bike. The vn750 is a hot ride for what it is, but you will be throwing good money after bad going this route IMHO. :hitanykey
 

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Discussion Starter #7
I've got one Vulcan and I'm buying another. I want to keep one stock and mod the other. I like the ride of the thing but I wish it had more punch. Moneys not that big of a problem if its to improve the bike the way I want to. I asked the question just to see if anyone had done it or knew info on it. I am going to buy a bigger bike this summer but like I said. I would like more out of one of my Vulcans.
 

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I've got one Vulcan and I'm buying another. I want to keep one stock and mod the other. I like the ride of the thing but I wish it had more punch. Moneys not that big of a problem if its to improve the bike the way I want to. I asked the question just to see if anyone had done it or knew info on it. I am going to buy a bigger bike this summer but like I said. I would like more out of one of my Vulcans.
Lance had custom pistons in his.I think and don't quote me on this but he used vn700 rods and pistons with a slightly different wrist pin location and had it bored maximum over bore,it takes a lot of measuring to get your clearances right at TDC,I also think he said he had some different cams ground as well,I never rode with him but there are several on here who did,that thing ran like a scalded cat ,is the word.

Sadly Ron has passed on. All his knowledge of the 750 as well,they called him "the Professor ",for a reason.
 

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Jerry is right here, you can go up by "honing" the bore to the next oversize, but if your thinking you can "bore it out" to get more displacement....you can't.

No one I know makes big bore parts for this bike... You'd need not only new pistons... But completely new cylinders too....or a full machine shop to drop in a larger sleeve. (the cylinders are aluminum with steel sleeves)

No one makes "hotter" cams either...

I'd say buy yourself a Honda VTX 1800....plenty of AM engine stuff floating around...
 

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No one makes "hotter" cams either...
sorry ,but you can get any kind of cam you want custom ground,but you are correct no one sells an aftermarket hot cam,and he said money really wasn't a problem.
 

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sorry ,but you can get any kind of cam you want custom ground,but you are correct no one sells an aftermarket hot cam,and he said money really wasn't a problem.
Ladies and Gentlemen, I present the $18,000 Vulcan 750...now a 1100cc. With just enough extra power to shear off your drive splines with just a twist of the throttle. Not as fast as any current 1000cc sportbike, but enough horses to frighten old men.

Bike still weighs 500+ pounds, but soon another $10,000 will get you a custom titanium frame, triple tree, and composite carbon fiber wheels to bring the weight down to that of an average Ducati.

Seroiusly... Do an earshave, rejet, add some nicer pipes and save the money for a more suitable platform.
 

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Ladies and Gentlemen, I present the $18,000 Vulcan 750...now a 1100cc. With just enough extra power to shear off your drive splines with just a twist of the throttle. Not as fast as any current 1000cc sportbike, but enough horses to frighten old men.

Bike still weighs 500+ pounds, but soon another $10,000 will get you a custom titanium frame, triple tree, and composite carbon fiber wheels to bring the weight down to that of an average Ducati.

Seroiusly... Do an earshave, rejet, add some nicer pipes and save the money for a more suitable platform.
Typical reply,I was answering the man's original question,but you have to cop an attitude.

Jerry jr. your way is not the only way and to correct your mistake,contrary to what you may believe you can not hone a cylinder out to oversize it must be bored to oversize honing a cylinder only roughs up a cylinder so the rings will seat.

I could care less what the man wants to do to his engine.like I said it has been done and it can be done ,is it worth it ? No.not to me either,parts and machine work alone would cost a couple of grand and I really don't see the benefit being worth the cost either.

It is not for me to say whether it is worth it to him nor you.Put down the Mountain Dew and step away from the computer,you don't know what you are talking about on this subject and it shows.

Have a nice day.:)
 

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Don't think I was "copping an attitude". ... Just joking around.

And when I installed the next oversize piston in my dirt bike, the thing I used to widen out the bore was called a "hone" .... Sure one could spend the money and take it to a machine shop where they would "bore" it out for you, but those of us that did our own work couldn't afford a machine tool to do this.

But yes , your right. Most folks don't hone, bore or anything but take their cylinder to a shop to get it done... And by that your terminology is correct.

The point was already answered that you really can't go much bigger than stock oversize.... But yes you can throw alot of money at anything and do what you want.... The question posed by me and others was that we didn't see the point....we did not say the OP shouldn't.

Better ???
 

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Don't think I was "copping an attitude". ... Just joking around.

And when I installed the next oversize piston in my dirt bike, the thing I used to widen out the bore was called a "hone" .... Sure one could spend the money and take it to a machine shop where they would "bore" it out for you, but those of us that did our own work couldn't afford a machine tool to do this.

But yes , your right. Most folks don't hone, bore or anything but take their cylinder to a shop to get it done... And by that your terminology is correct.

The point was already answered that you really can't go much bigger than stock oversize.... But yes you can throw alot of money at anything and do what you want.... The question posed by me and others was that we didn't see the point....we did not say the OP shouldn't.

Better ???
Yes,thank you,I just like you like to yank peoples chain on occasion and occasionally you leave one hanging over the plate and I have to swing at it.
:)
 

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Yes,thank you,I just like you like to yank peoples chain on occasion and occasionally you leave one hanging over the plate and I have to swing at it.
:)
That's OK... You keep swinging whenever you see the opportunity. I know I can go a bit far sometimes and not make it clear enough that I'm just lobbing a few in for fun. I just figure after all the years everyone knows not to take anything I "seem" to go off on seriously... Untill I actually write "seriously..." ;)

But yes oh god... I love my Moutain Dew....
 

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With a hone, the right measuring tool, and the skill, you can indeed "bore" out a cylinder to the next oversize, but it's tricky. I wouldn't try it on a streetbike. But back in the mid '70s I did it all the time on old 2 stroke dirt bikes. Didn't have money for a shop, borrowed the tools from the local farm mechanic.
 
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