Custom Exhaust - Tips?

[pete]

Hi all, not sure if this is the right section for this or not, but here goes...

When I finally get to the point of needing an exhaust on my 450 again, I'm thinking of designing my own for the look I want.

I'm not planning on changing the performance characteristics of the original, so will be hoping to use the same diameter, same length, etc. and just changing the routing of the exhaust. Mind you I may see if I can change to a lighter material than original to save some weight.

My initial thought is to save all of our toilet rolls and paper towel rolls (we go through a lot of these due to furballs!) and mock up a template with them.

Then I could perhaps get some pre-bent tubing and do up a proper template for someone to make the finished product for me. I've never welded before, so am assuming I won't be able to get a good quality end result.

Anyway, my main concern so far is what to do about the balance pipe that runs between the original pipes under the engine? My ideas for a design have the pipes right beside each other, so do I just run a bit of pipe between them at about the same distance from the headers as the original? Do I need a wider diameter pipe than the original seeing as they'll be much closer together?

Also, if anyone over here in the land down under has any ideas on where to buy pre-bent tubing, can you pass the info on?

I've searched and searched and searched on Google and can't find anything to answer any of these questions so far, so if there's a site out there I've missed that someone else knows about, feel free to pass that on too :-)

[salty_monk]

You don't have to have that pipe... I don't think it will make a lot of difference. Any pipe you make will likely be lighter as the OEM stuff is double skinned so 2 tubes 1 inside the other.

You're unlikely to get it to match flow of stock exactly but if you put a decent baffle in them & keep the stock air box you will likely be close enough not to make much difference.

Dan

[Billy Ricks]

I realize you are in Oz, but how about starting with something like this. They won't ship international but someone here might be able to help with that. I'd be willing to if you were to win it.
http://cgi.ebay.com/ebaymotors/Suzuk...mZ120325045554

[pete]

Dan: Thanks, I had a feeling it wouldn't make a lot of difference to leave it off. I'm planning at the moment to source suitable slip ons or similar baffles and keeping the stock air box. I found the 450 performance suitable for what I want, so don't need to change any of that.

I also didn't realise they were double skinned, so that should definitely make a difference!

And Billy: Not quite what I was looking for, but thanks for the offer :-)

I know where I can source a brand new UK made MOTAD 2 into 1 pipe for a very reasonable price, but I really want to change the look of the exhaust completely from stock, which is why I'm thinking the custom option is the one for me.

However, if you meant pick up a cheap second hand pipe and cut as appropriate to get the bends I need, then that's something I didn't think of and it's quite possible as I've seen many on eBay here that are probably the right diameter piping etc. If I can pick one up cheap enough, then for sure that's quite a good idea!

[Billy Ricks]

Yeah, I didn't mean the entire exhaust, just thought you could utilize the header portion from something similar. The newer GS500 pipes should fit your head.

[pete]

Good call, will have to keep my eye on eBay also, having a browse now and there's a few possibilities there.

Need to measure the header size etc. in case there's another brand that I can use also.

Header wise I may even be able to use my exisiting ones as the headers are in ok condition, just need some surface rust cleaned up. From the balance pipe back it's all bad though.

[pete]

Somehow I don't think will really end up affordable for me...

http://cgi.ebay.com.au/MOTOR-BIKE-MUFFLERS-AND-EXHAUSTS_W0QQitemZ130265943529QQcmdZViewItem?hash=item130265943529&_trksid=p3286.c0.m14&_trkparms=66%3A2%7C65%3A1%7C39%3A1%7C240%3A1318

[skidMarkNZ]

Somehow I don't think will really end up affordable for me...

http://cgi.ebay.com.au/MOTOR-BIKE-MU...1%7C240%3A1318

YUMMY!!!!

[pete]

Yeah I know, and not so far away from me to pick up either... but it just ain't gonna happen, I just know it. She who holds the purse strings ain't gonna let that happen!

[pete]

So anyway, bringing this thread back to life... how hard is it to make up a 2 into 1 as opposed to a 2 into 2?

I would imagine you have to be careful of the distance from the headers to the join and you'd need to have the headers merge in at similar angles right?

And then do you need larger diameter pipe?

Still confused...

[rudy]

Not hard to build your own 2-2. Check out what I did for my 400 Cafe project:





Cut the flanges off an old set of pipes and welded some mandrel bends on. Picked up all the pipe from Columbia River Mandrel Bending (http://store.racing-solutions.org/). Good prices and good people.

Ceramic painted them and wrapped with header wrap.





Now, these are straight open pipes. They're pretty loud, but for a little 400 this thing is ridiculously fast. Pipes, pods and jets. You can build yours to incorporate some mufflers.

I've seen that Columbia River also sells collectors. 2-1, 3-1 and 4-1. Good bit of info to know for my upcoming FJ project. You can get quite a bunch of stuff from these folks. They do it all. If you don't see something on their website, just call or email them and they'll get you what you want. Making your own exhaust system isn't that complex. There's only a few things you need to make sure about. Don't restrict flow too much with routing and such, and make sure there are no holes. A bit of an understanding of fluid dynamics will help too.

[pete]

Thanks Rudy, that's the sort of info I'm looking for, except I need to find 'em down here in the land of Oz...

Nice work on the cafe!

[rudy]

Thanks Rudy, that's the sort of info I'm looking for, except I need to find 'em down here in the land of Oz...

Nice work on the cafe!

Ah, crap! Forgot you were down under! Anywho, I'm sure you could find somewhere down there that sells bends as well. Take a look around on the net, ebay, and ask around at local exhaust shops. There's more people than just you looking for this kind of stuff. You just gotta find the places that they've found their stuff at.

[pete]

Yeah I'm still on the hunt at the moment. Can find nothing local via Google, so next step will be to try to find some time to call around.

Fluid dynamics are a little beyond me, but if I keep it as simple as possible and stick as close to the original length and diameter, I figure I should be ok.