Hey guys,

So I recently acquired a new coworker who used to weld professionally and to make a long story short, he might help me make some custom pipes for my 01 f4i. I was wondering if you guys could foresee any major problems with running them 4-2 and then duals back instead of the stock 4-2-1 headers and then single pipe system. I realize I'll have less back pressure and might lose a little hi-end power, but if anything, it might help even out the torque spread a little too, right?

 

You might need a remap. Make sure it stays 4-2-1 and then splits to 2, it would be enough to make it 4-2-2 but make an H-link somewhere so they are connected to each other. I have double cans in my F2, it possibly could use a little tuneup by lifting the needles or richening up the mixture a little, might lure out a few extra horsies too but it runs fine like this too. And sounds pretty cool, specially when motor braking. I would not change the header itself cause there's a loooot more science to their shape and lengths than you would think but there's not that much that can go wrong by playing with the rear part.

 

My prediction: Neither of you will get around to it.

Failing that, I'd put money on it looking, sounding fitting and running like a bag of crap... if you ever get it working it will be down on power and will have cost you a fortune.

Forgive my optimism. Did your coworker weld stainless with TIG? A mig welded exhaust would look laughable.

 

Interesting comment since I already said I have them, have had them for over a full season, the bike could use slight tweaking but so slight I haven't even bothered to do it. It cost me about 100eur, I made the midpipes myself, I Mig welded them and ground the seams down. And it sounds very good to my ear, has a throaty roar when given proper throttle. Yes the bike did lose 1-2hp but there's plenty left to not bother me at all. And if I want more power I just take the Daytona

 

Is that a joke?


MIG'd SS pipe

 

Oh, forgot, the answer to that question would be yes.

 

I was responding to OP's desire to make what appeared to be a complete exhaust system... Although blowing 100 euros and your time on a ratty looking midpipe that costs you power and runs badly is hardly a resounding success.

As for the MIG welded join, it always looks ****e in comparison to a decent TIG weld and that is no exception.

 

Sure, TIG'n looks better. But there's nothing laughable about a good MIG job - which is what you said. MIG is about being practical, and since it'll be underneath your fairings, it doesn't need to be a beauty contest. Unless you are a pro-welder yourself, I'm pretty sure that his pro-welder friend knows a lot more than you. You need to relax. Thousands of people build custom exhausts every day with good success. Matti's Triumph also has a completely custom can on it. It runs great, and looks amazing.

 

Oh well, everybody's entitled to an opinion I guess. No matter how hard you try you can't please everyone so I just try to concentrate pleasing myself...

Haven't ran the triumph yet with the can as it is still incomplete so can't promise that yet though but the original can was so oversized it looked like the bike had docked with Saturn 5 or sth...

 

Like my 954's "bazooka" OEM exhaust, I bet. I chopped it, I think the bike lost about 30lbs! (of course the bike lost half of it's power and bogged constantly)


So long as your pipe is sealed - it'll work just fine for you (but you already know that )