Purposely dent a Titanium headpipe?

27 replies to this topic
  • swatdoc

Posted May 24, 2009 - 04:42 PM


Gray - I don't see any "high-flo" pipe listed for the Yamaha 450's - only the maga and powerbombs in either stainless or titanium

  • grayracer513

Posted May 24, 2009 - 04:58 PM


Looks like you're down to swapping for a Power Bomb, or clearancing the header you have.

  • KJ790

Posted May 24, 2009 - 05:21 PM


I know what they look like on the inside , it is exactly like the resonator that has been on Honda 450R midpipes since 04 , and exactly like the original resonator designed 100 years ago by some guy named Hiemholt or somthing like that , a can with a tube with a few holes in it through it , thats what a resonator is , I dont need to talk to FMF , I know the man that designed them for FMF , his name is George Luttig , he used my fuel injection systems on the racing jet skis he used to build , he is an expert engine tunner and he probably saw something when he put one on the header when he was doing R&D at FMF that he liked , but I belive it has a bigger impact on noise than power , we have a dyno too and every engine is different and not everybody will get the same result with the same part , I just think people would be more apt to buy a power bomb than a quiet bomb if you know what I mean, George also designed the CHAMBER CORE witch I dont think you can get anymore because they only work when the tip is very large and hence the pipes check loud at 20" even though they are not loud at full throttle under load , those cores produced very broad torque curves and impressive dyno charts

The factory 4 and the V1 factory 4.1 used a chamber core and they were loud, but they did perform very well. The V2 factory 4.1 uses a tapered core and seems to perform the same as the V1 4.1, but it is a little quieter and doesn't seem to burn out packing as quickly.

  • swatdoc

Posted May 24, 2009 - 09:41 PM


actually i already bought a brand new powerbomb - and that doesn't clear either. the megabomb wasn't even close.

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  • swatdoc

Posted May 24, 2009 - 11:41 PM


hey guys here's another question - since the 4.1 FMF muffler is listed as a "slip on" and will mate up to the stock head pipe, I'm wondering if another manufacturer, say MRD, Pro Circuit, etc's "slip on" header, which is made to slip onto the stock muffler would mate up to my 4.1 rear? The FMF muffler does come with 2 aluminum sleeves to match the muffler's midpipe up to the stock diameter header.

I am totally kicking my ass right now for tossing my stock headpipe in the trash, thinking I would never need it! AHHHHHHHH!

  • grayracer513

Posted May 25, 2009 - 05:49 AM


MRD is a custom shop. He can make you anything you ask for.

  • swatdoc

Posted May 25, 2009 - 11:14 AM


well if FMF can't help me when i call them tomorrow, MRD will be the next call i make then!

  • swatdoc

Posted June 07, 2009 - 02:35 AM


Well FMF wouldn't do anything for me, and I've been using their pipes all the way back to my 1975 CR125 Elsinore! How's that?

Now, on the other hand, if you wanna talk about a company that takes care of people, MRD I think is gonna beat everyone hands down. I called Dave at MRD, and he actually knew about my problem from reading about it on this forum. Now get this - Dave had a stock 07 header in his shop he wasn't gonna use - and he offered it to me for free! Can't ask for a nicer guy and someone who cares about the sport and fellow riders!
Of course I'm gonna reimburse him for the shipping costs and his time, but what a great guy - thanks again Dave!!!!

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