| Author | Message | ||
     Piratius |
Hey guys! First post here on BadWeb, but I've been lurking on and off for a few months! I'm fairly new to motorcycles, but not to modifications/engines - I installed a custom twin turbo kit on my old 3.8L mustang, and have been messin' with Jeeps for about eight years  Anyways...the Blast is my first motorcycle, and I'm really enjoying it so far - I've been riding it for about 5 months, and put about 1,000 miles on it in that time. When I bought it, it only had 700 miles on it, and so far, it's been...a blast. [/groan] The only things it needs will be a new back tire (the Original tire is pretty hard, and feels wiggly when I get the bike leaned over!) Long story short - Like almost all of us Blasters, I'm thinking about a custom exhaust for a little more power/tone. I have a welder and can weld, so I want to fabricate something myself. The question: what kind of interface is there between the header pipe and the head? I see on mine that there is a flange that pulls against the head studs - but I can't find a good picture of what the header pipe itself looks like behind that flange. If I want to build an exhaust myself (with a supertrapp muffler, for example) do I need to cut a stock header pipe up? Or does someone make just the top part of the header pipe that I can weld my own system onto? On a more technical note: I see that most of the header pipes are 1 5/8. Is there a particular reason not to step up to a 2" pipe right at the muffler, if I had access to a 2" ID muffler for cheap? Seems like that jump would be pretty insignificant unless it will slow down exhaust velocity and hurt performance. Thanks again you guys :-D -Brad (Message edited by piratius on September 06, 2012) | ||
| Styxnpicks |
2" header is way too big. Velocity too slow. most of the good aftermarket pipes are 1 3/4" and 30-40" long depending on where you want your power to be | ||
| Piratius |
Right, I was saying to go from a 1.75" Header pipe to a 2" muffler, but only do the step-up right at the muffler itself. However, it's irrelevant now, because I was outbid on the crazy low price on the muffler I was looking at (and I decided I'll just get a new muffler when I build my pipes!) Well...I waited before posting this, because I did a lot of digging, and it looks like the exhaust clamp/flange slides over the pipe, then needs a retaining ring to be installed in a groove at the end of the pipe, which keeps the exhaust clamp/flange from sliding off the end. However, if I'm making my own header, do I just source a new exhaust retaining ring, slip the exhaust clamp onto the pipe, and then weld the retaining ring onto the end of the header pipe? Seems like it makes sense - but does it? The OE headers have a groove, whereas any pipe I use that's not originally part of a Buell/Sportster exhaust won't have the groove for the retainer. I found a retainer that can probably be welded to a straight pipe, but is this what others have done? Just making sure I'm not trying to re-invent the wheel! (Message edited by piratius on September 07, 2012) | ||
| Ezblast |
2" should be the last step for 6" on a stepped constant radius header going into a 19" to 21" 4" suppertrapp can with 18 discs on the can. See this link - lol - 1/2 way down the page - http://www.badweatherbikers.com/buell/messages/201 64/6806.html?1346989846 EZ | ||
| Piratius |
Alright, so...it's amazing what doing even more Google searches turns up! At the very bottom of the first page of the link below, there's a guy who builds his own exhausts for Sporsters. All different styles, but the big thing, is that he uses a very short chunk of slightly larger exhaust pipe welded around the primary as his retaining ring. Seems like a lot easier than buying odd sized retaining rings and attempting to weld the super-thin steel to an exhaust tube! Link is here: http://www.hdforums.com/forum/sportster-models/687 096-making-your-own-exhaust.html Slightly annoyed that it took a few hours of digging, researching, and mucking about to realize someone had already figured out a much easier and simpler way to do what I was trying to do. However, it seems like the easiest approaches might always be best! What do you guys think - do you do it that way, or do you have another secret method when building your own header pipes? -Brad | ||
| Piratius |
Thanks for the link, EZ. I like that system, I was going to try to build something a little less smooth than that, but still a bigger pipe/less restrictive muffler than stock. Alright, it looks like I should dig through the shop and find my scrap pipes, and see how bad I've gotten at welding. I was never a pro, but I can lay down a decent bead. Now that I've got a decent idea in the direction to go, I know what to start messing around with! Eventually I'll try and post pictures of what I come up with. For the meantime, here's a pair of my Blast, stock (as I received it)   Since then, my only mods have been wearing out the rear tire (trying my best!) and removing the rear upper belt guard. Next up is cleaning up the undertail/rear end (dremel time!) and building an exhaust. After that, maybe doing the intake mod & re-jetting! -Brad (Message edited by piratius on September 07, 2012) | ||
| Sycho |
Bike looks clean!! Everyone will soon chime in on "lose the Dunflops" keep us posted on your mods., and welcome to the forum. | ||
| Piratius |
Thanks for the kind words! Yeah, I know the Stock tires are garbage. Plus, they're the original 2003 tires, so they've hardened horribly where I haven't worn them down, which means as I get leaned over, the bike feels wobbly out back! (I'm still about 1" away from the chicken stripe on each side) When I can justify buying a set (over the winter, I think) I'm going to buy a Pirelli in the 140/70r16 size as advised on a ton of threads. I'm looking forward to the wider rubber, as well as having new rubber on the bike! I'm scoping out bits to make my exhaust - I'm thinking that either a 1.75" or 2" supertrapp muffler would be great, and just practicing my welds a LOT before I actually buy nice bends and attempt to make something nice! If I find a smoking deal on either size muffler, I'm liable to grab it and not worry about the choice later. Anything is going to be better than the super heavy, restrictive stock exhaust I'll keep posting pictures as I modify stuff -Brad (Message edited by piratius on September 07, 2012) | ||
| Ezblast |
The bike looks beautiful! Do yourself a favor and ditch the Dunlops - Pirelli stock tires are cheap and about a 1000 times better - no following road rain grooves, great handling, much better wet control, better braking ability - really the Dunlop is the worst tire to own. EZ | ||
| Piratius |
Yeah, the stock tires are pretty bad! Was going to jump up to the 140/70 series and not look back, so it's definitely on the list of stuff to do - definitely before next spring, hopefully a lot sooner than that (pending approval from the wife!) Just scored a plastic undertail/license plate shipped for $20 on ebay, going to pull my pristine one off, and dremel up the spare in an attempt at making the tail look a little sleeker/sportier. I'm going to shop around and pick up some cheap bends and start practicing my welds in prep of fabricating my own intake & exhaust. I'll keep posting pictures. Should I just use this thread and change the title, or start a new one of all the pictures, and do a slow, bit-by-bit build thread? I don't know how far or extreme it's going to get, but my Mustang went from a stock 3.8L v6 to a 370hp Twin Turbo monster. Hopefully I'll find the time and resources to make this little bike move pretty good! (Message edited by piratius on September 08, 2012) | ||
| Ezblast |
yeah - the140/70&110/70 are a great choice - but the dunflop are dicey. Fist mod - ditch them, then you'll really appreciate the bike! EZ | ||
| Piratius |
So I got a junk piece of 1.75" pipe. Cut it up into 7 pieces, and welded it all back together. First four welds sucked - mainly due to my using an angle grinder to make the cuts. If they're uneven at ALL, it's really hard to get a good weld. I borrowed a chop saw, so I'm going to try again tonight to see how well I do. Hopefully the next 7 welds will be a lot better! I have a few mandrel bends coming in on Friday, so I'll be ready to start making a starter straight pipe/proof of concept pipe next week! -Brad | ||
| Piratius |
Hey guys Just checking back in - I know a lot of people make first posts claiming that they're going to do X, Y, or Z, and then never follow up with photos or updates. I'm not that guy! I spent a week practicing my welding on the relatively thin exhaust tubing (I bought several diameters, etc) and got pretty good. Then, last night I pulled off the stock exhaust, and started the mental fabrication. Today, I took the big U-bend I'd bought, and started cutting! It was a pretty big radius bend, like 6" or so - and you could almost cut a leg off of it and bolt it onto the head. However, I cut it into two 90* bends with legs. On one side, I cut all but 1" of the leg off, and that's the first portion. I then took a piece of slightly larger exhaust pipe (that just slid onto the 1" of leg that I left) and cut a .5" wide piece. I then drilled 4 holes, and welded it up almost even with the end, forming the piece that the snap ring sits against. Now, I'm measuring/cutting the next bend - I cut about half of the leg off, and am test fitting. Hopefully I'll get a chance to tack the next piece up tonight. Needless to say, this is a full 1.75" exhaust, with an "almost" constant radius. There is about 1.5" between the two 90* bends. I'm not sure if I'm going to run a muffler or have it as a "race pipe" at the moment - modifying it to run a supertrapp muffler will be easy if I decide that I need to go that route. Pics to follow - assuming that I can get back out to the shop and get some time! -Brad (Message edited by piratius on September 25, 2012) | ||
| Piratius |
Pictures, as promised!     Hope this makes some form of sense! -Brad |
