Need Exhaust Help, designs

I'm really not trying to make this another i want to make an exhaust thread but i have no clue where to really start on this.

I have a friend who is great at welding. Naturally he has a tig, a nice miller matic and a few others. I have a lincoln flux that i've realized is useless for exhaust and i'll going to get a good tank setup later. But here's what i want to do.

I have lately noticed that the xj650 and xj550 have a lot of after market 4-1 setups. I have a D&D i got from a katana 600 and redid. Can was crushed but i was able to cut off the bad part and make it look factory. So i would really like to utilize it on my 85 FJ600. I have no exhaust except some down tubes i bought a while ago and honestly i want an exhaust whenever i first fire it.

I'm not a fan of a 4-2-2 but my whole reasoning for the 4-1 is it looks good, sounds good, and i'm not spending 200 bucks on a 20 yr old exhaust on ebay. Id rather spend it on something i can adapt.

My biggest problem right now is the room under the pan. I have the oil filter in the center i have to go around but then on the left side almost make a 90 to get the other side.

Well anyway i noticed that a lot of 650 and 550's have a similar design. I can weld a pipe in with a mandrel cut no problem. But if they have a header set up that flows over to the peg i can go from there easy.

Does anybody know the diamater of these pipes from the head or at least a picture of a factory or 4-1 under the oil pan. I'm curious and google isn't helping me with its vomiting of every xj out there.

 

Have a look at the parts fiche at http://www.yamahapartshouse.com. It will show you how everything looks, and how it fits together.

 

thanks k-moe but i would really like to see a close up of what it looks like under the bike assembled. As long as the 4-1 makes the turn before the swing arm i don't see a problem. I also want to keep the center stand if at all possible

 

looking for something like this but honestly just need the headers to where the collectors come together.
If i find something with a muffler i'll take that too.

http://www.ebay.com/itm/Yamaha-XJ55...501-/161668050407?hash=item25a42aade7&vxp=mtr

 

Ive got a 4 into 1 on my xj600. Dont know if the pictures might help but it does run down the R/H side opposite side to the kick stand.
Let me know, im happy to post some shots.

 

That would be great if you could. I really need the underside pics more. I took a 3 week break on it sinceit was starting to piss me off.

 

Just make sure you clear the oil drain plug, would be big pain to pull pipe for oil change