swapping out my xj650 engine for an xj900 seca engine

I'm swaping out my xj650 engine for a xj900 seca engine and I'm installing pod filters.

right now it is stock with no mufflers (my exhaust ends after the 2 into 1 pieces), i put on lower handle bars, and i'm looking for an 05 suzuki sv650 headlight cowling to paint black and retro fit to my bike.

any issues you think might come up such as jetting, air flow restriction from the 650 carbs, mounting brackets, exhaust, ignition, the drive shaft connection?

also any suspension mods suggested for the slightly heavier engine?

 

what year of xj900 seca engine are you using?

 

I would recommend stiffer rear suspension because I know the XJ650 (or at least my maxim) is WAY soft. I only weigh 240 and I bottom out often.

Also beef up the front.. not sure about how though.

 

its a 1983 xj900 seca 25,000 miles

I weigh 185 with gear so i don't think it'll be a big deal lol

i'm thinking i'm going to want to increase my trail slightly for more stability at high speeds. the bigger engine is sure to go faster and as the bike is i feel a slight wobbling tendency at around 115- 130mph.

I read in another thread that the engine change is a straight swap but it didn't talk about rejetting. I don't want to mess with the carbs unless i have to

 

I'm guessing your looking at that 900 motor on e-bay. I don't want to be a wet blanket but 500 shipped with no carbs or starter seems a little rich. Esp since you have a heck of a lot of work to do once it arrives.

 

IDK if the seca's are stiffer, but I would hope so.

I havent seen anything past 75 on my max yet (1. nowhere around me to go that fast legally or otherwise, 2. I am afraid to push it with the bull bars on it and bad fork seals and soft rear suspension.. just seems too unsafe for me)

 

You are going to need a set of BS-34 Mikuni's to get that 900 Powered.
The BS-34 Mikuni's need Velocity Stacks if you run Pods and Straight Exhaust.

In my life, ... I have only seen 1 900 Engine in 750 Frame.
The uses a Stock 750 Fuel Tank and raised it 3 Inches.
The Bike looked like it was designed by the Furry Freak Brother's after an all-night Bong-a-thon.
I wouldn't even try to ride it, ... it looked so Hillbilly.

I have 2 - 900 Engines.
I was contemplating putting a 900 Engine in a 750 Max Frame and doing it right.
That means adding a 4-1/2 Inch stretch to the Frame in front of the Swing-arm Pivot, raising the Center Tube 2-1/2 Inches and then getting a Fuel Tank fitted that wider than it is tall.

It ain't Plug-'n-play.
If it was easy; I'd be riding one!!

 

This thread said something about it just being a bolt on swap.

http://xjbikes.com/Forums/viewtopic/p=22001.html

was it just talking about bolting an xj900 top end on to an xj650 crank case?
if thats what was meant then thats what i'll do.

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1980 xj650 special - 32,000 miles
thinking of swapping a 1983 xj900 seca engine in

other bikes

79 gs425L (project bike)
84 magna 700 (runs with dead cylinder)
80 kz1000 (new project bike haven't touched it yet)

 

Logan, you will want a Seca spiral 18 inch rear rim, not your 16, and the 900 has a 1 1/2 inch longer swingarm to help prevent wheelies, and as others have said, you need the carbs and ignition brains too.
I think you even need the coils, as they OHM out differently.

Sounds like an awesome project if you ask me.