750 engine in a 650 Maxim.

Long story short, my brothers 2016 Soft Tail Slim(with loud pipes)and a 103 cubic inch engine is slightly faster than my 82 650 Maxim with 13,000 miles with a good state of tune. We were at 55 mph or so and I was already waiting in 3rd gear. He was just barely pulling away. If I had 2 or 3 more horsepower, I would have stayed even.

I tried the search function and nothing came up for 750 engine in a 650 frame. Is it a direct swap? Can you put a 750 crank and con rods in a 650 case? I understand the Jugs from a 750 fit the 650 case but thats only a 40 some cc increase in displacement. I found this place that modifies your cams and would be willing to get some off of ebay and see if I could get some higher compression pistons(11 to 1? I use only 91 octane already)

https://www.megacyclecams.com/catalog/catalog.pdf
256-40
.410" 250° 105° 20 btc/50 abc .005"
.410" 250° 105° 50 bbc/20 atc .007"
Drag race. Mid-range torque. Great throttle
response. Use racing pistons and springs.


I know getting a V Max would be easier but I'm interested in fixing what I already have.

 

HEre ya go:

https://www.xjbikes.com/forums/threads/xj-parts-catalog-section-e-engine.44640/#post-395179

 

Bolt in with 750 engine and carbs has been done many times

 

Or find an xj700 and run away from him. Not too many harleys around that can run away from my 82 650 max. Buddy tried with his 1500 vulcan... didn't work out so well for him. My "little" 650 gets more respect now.

 

Thanks for the help, guys. Has anyone put the cams from a 750 into a 650 and noticed an improvement? I see them on ebay for a reasonable price. Are the cylinder head ports, combustion chambers, and valve sizes different between 750 and 650? I thought I remember reading over the years here about the cylinder blocks being interchangeable from 650 to 750 is that right? If so, I might get 750 cylinders, a head if they are different, cam re-do from megacyclecams, play with jetting, and this...if the wrist pins are the same size as a 650.
http://www.speedmotoco.com/product-p/bbk015.htm

Will make 761 cc with the 650 crank. If that ain't enough, hunt for a 750 engine and get 818 cc.

 

The Vulcan has only 64 hp. http://www.motorcyclespecs.co.za/model/kawasaki/kawasaki_vn1500_vul_nomad.htm The new Harleys are not like the old ones. The 103 made 74 rwhp on a dyno and the 107 made 80 rwhp in a youtube video. They still shake like somethings wrong with them but they are a lot faster than I remember from 10 years ago. I got to ride a 2018 Road King that has a 107 inch engine and there is a ton of power right off idle and it's likely faster than my brothers bike. My nephew got it a month ago as his first bike. Wouldn't listen to me about getting a normal size bike to learn on. His neighbor got one in a different color. Now the extended family is looking at Indians. I got mine in the spring of 2008 and loved it ever since. I don't want to hear crap from them about my old, almost as fast bike that cost a quarter(half in my brothers case) of what they paid in sales tax on their $20k bike. I want it to be my same old, but noticeably faster bike that cost a fraction of the sales tax on a new bike.

 

The cam info is in the link provied earlier, just scroll up a bit.

People have used that kit with varying results. I think the general concensus is that it's better to get a Xj900 if you want to go that big. Keep in mind that there are a lot of seals and gaskets that you will need that are not included in that kit. You'll also have to factor in having the bores machined, which is where the problem lies. The 750 liners don't have much left to them once they are bored out for those pistons.

 

Go here. nitrousexpress.com
Show the Harley guy your nice new saddle bags. just don’t show him the canister you hide inside.

 

information overload has directions for engine swaps and has a section on cams too.

The Information Overload Hour.