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I know that this may be in the wrong section but i had (10) 10 gauge stainless steel plates made to block off the exhaust vavle opening in the midpipe and would be willing to sell (9) them for $10 a piece and that would just cover my labor. Basically if you remove the exhaust valve from the exhaust midpipe, you are left with a big hole in the side of the midpipe, this plate bolts on using the same bolt holes. I don't know what this does to the bikes performance, i just didn't like the thought of the vavle actually restricting the exhaust as much as it did. I'll post a picture tonight once i get it installed. $10 for the plate and $2 to ship to paypal [email protected]
 

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I don't know what this does to the bikes performance, i just didn't like the thought of the vavle actually restricting the exhaust as much as it did.
Removing the valve though would make for fairly messy flow through the empty exhaust valve anyway so I'd be surprised if this is better than leaving the valve in place. I'd expect the valve would be far less restrictive if you left it in place rather than remove it. And why did you use heavy stainless instead of aluminium plate?
Personally, I think your $100 would've been better spent making a straight-through replacement for the valve housing similar to the HASS thing.
If you're going to ask people to pay for these I think you should've done before and after dyno runs :)
 

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Yeah, ok thats what I thought....... need more then block off plate when that gets yanked, cause you loose mid and low end without it.

I was same way thinking yeah restricting valve, remove it, once I did I could tell mid and low end bombed, but top end got a little boost it seemed. With a PCIII and a good map or a custom tuned map you can really get it to scream, usually still have a little low end lag though.

Yeah that part probably does not add crazy weight and its sprung, but yeah saving weight is always good, so removing the valve since its titanium and adding the stainless block off, you either broke even or gained a little weight.

But for sure, I would do a before and after dyno run to prove the increase and at what rpm. :)
 

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Yeah, ok thats what I thought....... need more then block off plate when that gets yanked, cause you loose mid and low end without it.

I was same way thinking yeah restricting valve, remove it, once I did I could tell mid and low end bombed, but top end got a little boost it seemed. With a PCIII and a good map or a custom tuned map you can really get it to scream, usually still have a little low end lag though.

Yeah that part probably does not add crazy weight and its sprung, but yeah saving weight is always good, so removing the valve since its titanium and adding the stainless block off, you either broke even or gained a little weight.

But for sure, I would do a before and after dyno run to prove the increase and at what rpm. :)
Yes, you do lose some midrange (bottom end doesn't matter since the bike doesn't make tractable power below 4000rpm even with the valve) but for the road it's not significant in a 900cc+ engine.
The valve is titanium but ti is still twice the weight of aluminium. There are _very_ few places on a motorcycle where you need the strength of titanium compared to the weight saving of aluminium - not to mention the cost and ease of fabrication.
The OEM titanium header is still heavier than a good aftermarket steel race header but at least it doesn't rust :)
 

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The valve is titanium but ti is still twice the weight of aluminium.
Yeah I agree on aluminium would be a way better choice then stainless or the ti for sure, way cheaper and easier to work with, heck you could use a air nibbler easy on that or other methods.

I was just trying to think outloud the reasoning behind stainless. :)

The OEM titanium header is still heavier than a good aftermarket steel race header but at least it doesn't rust :)
Yep would not argue that, it also has a nice color to it after a couple heat cycles. :)

Also I would agree with the low end, and I know its not a dyno or etc. but before I removed it my 02 954 would snap up at around 2k rpm's and when I removed it, it would not.....so according to my redneck dyno I lost low end. :smilebig: :rotfl: :hmm:
 

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Also I would agree with the low end, and I know its not a dyno or etc. but before I removed it my 02 954 would snap up at around 2k rpm's and when I removed it, it would not.....so according to my redneck dyno I lost low end. :smilebig: :rotfl: :hmm:
The loss of midrange was very noticeable on the racetrack if I allowed the tach to drop below 8000rpm through a turn.
 
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