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I guess the next question is, how to use the CRs velocity stacks while ensuring adequate filtration but allows enough air flow
So given the fact that (as you mentioned) you are going to be living at 1/4 to 3/4 99% of the time and its agreed we are talking about a very narrow range where it is going to come into play (and that is assuming all is well and everything else downstream), why don't you just go with the Dynoman's recommendation to run separate K&N filters?

I think "sometimes" keeping the airbox is overrated. If you just make sure they get a sufficient supply of clean air and it enters the carburetor through some sort of velocity stack (or whatever you want to call it) that won't create a whole bunch of aerodynamic fungus that will upset the apple cart.... (ala the CB750 syndrome) then all will be well with the world. I think delving too deeply into things in your situation is like chasing moonbeams. You will have to spend a kings ransom on donuts to realize any gain assuming there is any to be had.
Personally I would just buy 4 good quality individual filters and hopefully the Dyno guy can tell you exactly what works and back it up.

Just on a side note.... and it really doesn't belong in this thread. My GL500I has different length intake manifolds. the runner diameters are equal, the runners in the Y shaped boot between the carbs and the airbox are equal length and there isn't anything anything in the airbox that is of any real interest. So there you have it... different runner lengths.

If you were running a LSR bike it would be a different story, but as it is I think you are better off taking their advise and spending some of that donut money on one of those A/F setups because I believe it will come in handy. You might still want to do some slight changes after the dyno setup just to address any real world drivability issues. I'm talking through my hat a bit there, because I don't have any firsthand experience with any of those kits. I am going to buy one as I'm starting from scratch and it'll probably pay for itself more than once. I'll let you know how it works out, but it won't be until after the monsoon season.


Disclaimer:

I may have missed something in this thread, but my ADD prevents me from re-reading it, plus I haven't had my second cup, so apologies if any of this is redundant or moronic.... .

You should probably not take any advise from someone who uses intake manifold spacers like this.

Manifold spacer.jpg
 

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Discussion Starter #42
Good point Cyorg.

I guess I'm getting to the point with the Z1 where I'm splitting hairs trying to get the best performance possible (without buying a second head to port and polish plus cams).

I'm really happy with the UNI filters I'm running now, so I guess I shouldn't complain
 

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from memory you have total frame interference behind the carbs, so you can't run long ram tubes? I'd run as long a tube as possible, then as good a filter as you can.

i think the cv carbs are happy to have an much damping upstream from them as possible, and the more you try to make one act like a slide carb (improve response) the crappier they become. whereas the slide carbs don't care what's upstream in broad terms, but will work with all the usual inlet trumpet ideas.

i recall some guys out here back when there was a big naked series running zrx11 or 12 who ended up putting flat plates over the sides of the carbs area (filling in the beloved open triangle-ish) to stop the air flowing by screwing up the jet at high speed (220km/h +), as they were having a lot of high speed jetting issues. the plates gave a sort of stable area of air around the carbs, backed by the rear inner guard or whatever is back there, and made it much better. an open fronted airbox if you like, which is what i think is the thing here. but that's hard to filter in trad airbox terms, so you'd still need the individual filters of some sort.

in reality they were breathing a lot of hot air from over the engine, which will make the theorists scream about the shit they like to scream about. didn't seem to matter much at all - they went faster.
 

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from memory you have total frame interference behind the carbs, so you can't run long ram tubes? I'd run as long a tube as possible, then as good a filter as you can.

i think the cv carbs are happy to have an much damping upstream from them as possible, and the more you try to make one act like a slide carb (improve response) the crappier they become. whereas the slide carbs don't care what's upstream in broad terms, but will work with all the usual inlet trumpet ideas.

i recall some guys out here back when there was a big naked series running zrx11 or 12 who ended up putting flat plates over the sides of the carbs area (filling in the beloved open triangle-ish) to stop the air flowing by screwing up the jet at high speed (220km/h +), as they were having a lot of high speed jetting issues. the plates gave a sort of stable area of air around the carbs, backed by the rear inner guard or whatever is back there, and made it much better. an open fronted airbox if you like, which is what i think is the thing here. but that's hard to filter in trad airbox terms, so you'd still need the individual filters of some sort.

in reality they were breathing a lot of hot air from over the engine, which will make the theorists scream about the shit they like to scream about. didn't seem to matter much at all - they went faster.
yep disciussion is good
TL1000R
hammers out somedecent hp and trq stock and has a decent usable powerband
of course it has a large airbox of thick plastic with the stacks close enough together at 90 degreesthat a goddam mexican jumping bean could do thedistance
welp srad also dictates large ducts oneeach side and if you desireto naked the tlr or tls and leave off the ducting you loose 8hp
take off the aibox lid pffft ferget it that dog dont hunt
on that config the v twin 90l motor creates like a dueling hp tubas and the frequency of all the parts gives extratune jumping across the intakes above and beyond what indi tuning can do,i guess
notice the quite similar volume tubes sam has fabbed for his naked climber (sam builds the quickest tl motors bar none )
looks like good fun that climbing !
 
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