Power??

What EASY mods can I do to my XJ650 to get it a little more performance enhanced. Air filters?? Is there a specific kind of aftermarket filter I would need to get to replace the stock unit. How big is the hole from the carb to the filter? I already have a Kerker 4 into 1 exhaust. Im not much into engines so sorry for the dumb questions. Thanks

 

I would say that the easiest mods would be:

4 in to 2 exhaust
High flow K&N Air Filter
Bigger Carb Jets

That could be a start anyway

 

how big is the inlet or outlet or whatever for the airfilter or what filter what work best, im going to get k&N most likely.

 

If you are going to get a pipe and rejet, you probably should go to pods too.

 

Pod filters, in my experience, are bad news unless your doing major carb work, and are planning on spending months tuning them correctly, and are going to retune once a month or so.

Stick with the stock airbox, a stage 1 carb kit, and a good aftermarket exhaust. That's probably be expensive enough...

 

There is an X pipe on ebay right now, best pipe for the money, but LOUD!! basically goes 4:1 then out each side with a short collector. Expensive too, but I remember seeing reports that these pipes make excellent power at both ends of the spectrum. Maxi X pipe

 

If you're running a 4 into 1 exhaust, are you sure the bike wasn't already re-jetted? I've found the best mod is a properly running, correctly tuned engine. Then you can benefit from increased air, fuel, and exhaust. But it also depends on what your goals are. Most will tell you that if you're looking for substantial gains, a bigger bike may be in order.

 

For the cost of all these suggested modifications, and the time needed to install/tweak/tune, it makes more sense to find a decent used XJ750 engine and slip it into your bike.

A pipe, jets, and air filters will be ~$400 unless you're buying used stuff.

A used 750 engine is about the same price, and will produce far more (and better!) power than your 650 ever will.

And you can either sell your original 650 engine, or mothball it for a spare.