Just_Nick

I'm curious if anyone has tried removing the snorkel and using spacers to lift the tank a little like they do on the SV.
Or maybe use 5/8" spacers and flip the snorkel around?

Hawkrider

Not recommended. Some have done it with limited success, but most have had wierd jetting problems, and I've even heard of the bike running strangely with a side wind because the airflow isn't clean. Go for it, but I don't think it'll gain you much....

killer5280

I have a spare airbox and I have tried a few things just for kicks. Removing the snorkel made it run worse but it did make a cool intake honk.

Just_Nick

Thought so.

mboe794

Don't do it. I tried it once. Side winds caused it to stumble. I switched back to an un-molested lid.

Just_Nick

I wonder what flipping it over and raising the tank would do?
Or removing it, raise the tank, and put plastic covers on the sides to block side winds.

dakmatik

It doesn't sound like you would get anything good out of messing with the airbox like that. I guess you could just try it. If it doesn't work, you swap back to how it's supposed to be.

mikstr

Here is what I have done with success :

- carve out the snorkel (remove divider), smooth out the step (with silicone, smoohts out airflow) and remove all excess material from inside; end result if pretty close to a doubling of the inlet surface area
- cut out one 1" hole per side on front sides of lid close to front (hid away by tank when done, so as not to be vulnerable to rain or side winds)

This, together with a modded stock airfilter (another paper element glued in place, screen and backfire guard cut out) and proper jetting yielded about 2.5 hp and similar torque on dyno.

Tweety

I've tried a bunch of stuff with the air box and filter... And so far the only two things that gains anything is the velocity stacks combined with a K&N filter... And that was only after the filter is modified with the lip from the stock filter...

With stock stacks the K&N made me loose power in parts of the rev band gaining in others... Adding the stacks and testing the K&N without the lip it performed kind of like the stock filter with a bit more flow and a bit more power through out the rev band, but with a noticable dip in one spot... Add the lip and you get rid of the dip...

It's *** backwards compared to the stock filter (with stock stacks) where you gain a tiny bit by removing the lip...

All the other attempts I have made at modifiying the airbox resulted in either a combined net effect of zero with losses in one end of the rev bad and gains in the other... Or it ended up being close to unrideable as I had huge holes in the revband...

If you do anything, and I mean anything to the stock airbox (or the whole intake path) you end up with a PITA in jetting situation... Some things works on their own, but not together, some work together but not alone... All the above was combined with several attempts at rejetting... On a dyno... So it wasn't that the jetting was of for the applications...

I have more or less given up trying to figure it out... I have the stacks in there with the K&N filter + lip... It works with an otherwise close to stock engine... I'm not messing with it until I drop in a Stage 1 engine... Or Stage X, depending on my ability to restrain myself...

Tweety

Hm... That seems like an interesting idea to ponder, mikstr... It somehow never occured to me to remove the excess plastic inside the snorkel... I'll go have a look next time I fiddle... I got lots of time for it now... Damned snow...

mikstr

I have all kinds of interesting ideas, just not enough money (or a machine shop) to act on them all.....

Just_Nick

Same here, example being my SuMoHawk.

Tweety

Oh... not to worry... I have ideas... And tools isn't a problem... I just need more time... So unsurprisingly my bike may take on a new shape come spring...

Just_Nick

I am still curious the effect of spacing the tank up and flipping the snorkel. I mean, all that would do would pull cooler air.

Tweety

Try it and find out... But I have said it before... The VTR is notoriosly picky when it comes to the intake path... Usually what works on "all other bikes" doesn't work on this one... Dunno why... Just the way things are...

Just_Nick

Or ram-air. Has anyone tried that?

Tweety

That was tried on a few of the racebikes back in the day when VTR's was new and hot... As far as I know you really need a decidedly not stock engine to make any real gains from it...

Hawkrider

You also need to pressurize the bowls of the carbs if you do that, which in turn may require the addition of a fuel pump.

mikstr

Not sure about CV carbs, but I know on snowmobiles with non-CV carbs they get around this pressure differencial by simply venting the fuel bowls into the airbox, therefore equalizing the system (venturis and fuel bowls both read the same pressure at all times).

Hawkrider

Yup, same thing. Hmmmm....I wonder how the bike would run if you did that to a stock airbox? I know we don't have any type of ram air stock but I wonder if there would be any benefit on a stock bike.

mikstr

I cant see there being much to gain as there is no pressurization to speak of in the airbox to put the system out of balance, also both the fuel bowls and snorkel draw in fairly close proximity to each other, making the pressure difference negligible. Of course, it couldn`t hurt to try.