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Discussion Starter #1
Hey all,
I'm looking for the answer to a couple of questions on some new mods(new since I was last looking). They are the Norman Hyde Bellmouth and the air filters "FREAK".

How does the Bellmouth work? ie:what does it do, how does it improve, by how much and is it worth it.

The Freak, Cool looking setup but what are the pro's and cons. Is it difficult to R&R and has anyone here done it?

My ride is a '05 Blk Speedmaster. My mods are simple-K&N Air filter, K&N Carb kit, TBike Pipes, Leatherneck Jim Saddle Bags with EZ Brackets. Last spring I changed my front sprocket from 16T to 17T and this spring I'm changing back. The legs are too long and you loose the launch power.

I'm also looking at the cable gaurd from New Bonnie web site. Has anyone done this cause the factory one is crap. Any feed back would be great as I'm in the mood for something new for my baby.
 

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There has been much debate over airbox mods, and most people know my views, so I don't intend to restart here.

However, the Norman Hyde bellmouth is an expensive (but really good looking) way of doing things. Jenks (bolts) does a cheaper version (or at least he did!) or the cheapest version is to use a Polaris rubber bellmouth.

You're best off doing a search or using the sticky http://www.triumphrat.net/twins-technical-talk/91238-great-source-of-info-links-to-tuning-modifications-and-so-on.html

There's plenty to get your teeth into, which should help you to make up your mind!

Good luck ;)

Dave
 

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Actually, the cheapest solution is to just grab a dremel and open up the intake as wide as you can by removing all the plastic that is not required to hold the filter in place.
Fair point, but I was limiting it to a 'bellmouth solution'. I guess the cheapest solution of all would be to just remove the snorkel - but don't get me started on that...... :)

Dave
 

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Discussion Starter #5
O.K, back from work.
So it appears that Dave does not seem to agree with this mod and PokyJoe is all for it. When I bought my bike new in '05, their was this debate on whether to keep the air box or cut holes in it and so on.
I've decided to opt out of that whole mess till they came up with something that appears more thought out and stylish. That Freak set up looks pretty sweet. I checked out some of those links you sent. Great help! Thanks for that.
 

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Hey all,
How does the Bellmouth work? ie:what does it do, how does it improve, by how much and is it worth it.
I have just discovered some information on bellmouths direct on carbs which may be of interest - quoted from 'Classic Bike' magazine.

"It was discovered long ago that when the inlet valve slams shut, the gas thats heading through the carb bounces back. Easing the cam profile so that the valve closes more gradually helps but it doesn't prevent this. When the valve reopens, the gas reverses and gets sucked back again. Unless there is a bellmouth, or an airfilter, this gas will dissapate in the atmosphere. So a bellmouth is not just a gimmick, it acts as a sort of holding area for unburnt fuel mixture and stops it being wasted."

So, the bellmouth outside of the airbox will not perform this particular function, and would seem to be a bit pointless. IMHO, removing the snorkel may be worthwhile (and it costs nothing), and added a bellmouth is probably not, so removing the airbox is a better option than a bellmouth.

Dave
 

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the Norman Hyde bellmouth is an expensive (but really good looking) way of doing things. Jenks (bolts) does a cheaper version (or at least he did!) or the cheapest version is to use a Polaris rubber bellmouth.
the stock boots between the air box and carbs has a bellmouth (when you liberate it) that fits the snorkle opening too. my intake rubbers went south and replacing them, I discovered this little trick...maybe it's been posted before and I missed it...but it's a free bee.

after playing around a bit, I got the K&N filters...perhaps when I'm further along (come spring), I'll post the whole re-do I'm doing sans air box...my battery had altitude sickness, but the real reason is I'm not buying endless Triumph crap rubbers. The parts I'm making now should tuck it all together tasty enough to be presentable with or without side covers.
 

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Discussion Starter #8
It seems like a lot of guess work for a simple box as well as a lot of dollars for what? a couple of ponies? hmmm...I do agree that when I removed the snorkel and added a K&N that things sounded and responded better but dont you still need some kind of restrictor? Is their such a thing as too much air? Taking the box apart seems over kill and may jeopardize performance else where. I'm no tech or engineer but that would make sense.

I've been looking at T Bike cams and I'm corresponding with a fellow from there so I'll throw back what I'm told. I think if I want "REAL HP" I'm gonna have to go big. Something I will consider for winter 09/'10. In the mean time I have noticed by allowing the bike to breath a little better and along with a set of T bike pipes, it's really taken it to another level.

I DO NOT recommend changing your sprocket to 17t or greater unless you live in the prarries or do ALL straight and long hi-way travel. You loose everything you spent money on to gain!
My top speed prior to the change was 220Km/h, I dont think I need to go any faster than that. It is awfully quick! (and I love it):D
 
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