Topic: Best Air Filter Option

[dtmmil]

Ok, question about tintops air filter setup, how does it work when it gets wet, like when its raining, does the filter get wet? Curious about it, I did see his post about them.

[m in sc]

i disagree. if you get the stack right, then the speed and density are correct, and iou adjust your mixture to suit then yes, you can filter it and it will flow correctly. theres LOTS of fiddling w/carbs to get them right, but when you do get them right, they are okay. its not black magic, its a venturi with a pressure drop bleed system to break it down simply.

the biggest compromise IS the stock airbox as it was designed to work okay in all conditions and driving styles.. but not optimally.
the stock airbox has 4 velocity stacks built in which are needed. you get enough filter area behind that and compensate with the change in jetting, (which includes needles, pilots, slide cutouts, air jets, etc) and you can get it to work right. considering how small the stock opening is in the box it def bottle necks there. opening the hole opens the proverbial can of worms to a degree, and it goes on from there.

you cant tell me the optimal airfilter for that bike would be that trapezoid they stuck in there so that the airfilter can fit into a housing that is desinged to clear the frame rails. new boxes are a different ball game, resonance tuned, etc, but that ancient design on the cb is by no means optimal.


Ive been tuning fairly radical 2-strokes for almost 20 years.... im telling you, for a street ridden bikes it aint that hard. but it is time consuming. I think the biggest problem is it takes a lot of time, and usually money for parts. and some dyno time with a gas analyser.. just my .02

[mrbreeze]

I run steel dragon performance v-stacks, they have a screen that covers the throat of the carb.
http://www.steeldragonperformance.com/products_2.html
he also makes a breadbox type air  cleaner if you want to stay more stock. I personally think the stock airbox is big and ugly. my .02

AGREED!!!! Butt ugly and a major PITA to deal with. I am awaiting more fo on this steel dragon unit...sounds very cool to me.

[crazypj]

Ok, again my stacks have a very fine screen covering the throat of the carb

and VJM? what does that mean?

VJM=Vintage Japanese Motorcycle

 Interesting thing's about 'really fine screen'
1. it only keeps larger rocks out of motor, the dust particles that cause most wear go right through the mesh
2. the restriction on fine mesh can be as much as 65% of the area it's covering so you have way LESS airflow than stock

[Retro Rocket]

the biggest compromise IS the stock airbox as it was designed to work okay in all conditions and driving styles.. but not optimally.
the stock airbox has 4 velocity stacks built in which are needed. you get enough filter area behind that and compensate with the change in jetting, (which includes needles, pilots, slide cutouts, air jets, etc) and you can get it to work right. considering how small the stock opening is in the box it def bottle necks there. opening the hole opens the proverbial can of worms to a degree, and it goes on from there.

I wouldn't say it bottle necks at all, it supplies a good supply of air to the carbs which is stable and not influenced by side winds and turbulence, which is one reason why modern performance bikes still run airboxes. Unless you are running a big port performance orientated CB there is no need to alter the stock airfilter system at all.
Actually, because of the restricted flow of the heads on these bikes {sohc/4's} the airbox, which wasn't just designed to fit,  was engineered to work as efficiently as possible in all conditions, is the best filter system on these bikes, they actually aren't that restricted and flow well, i have used them on big bore cb's with big ported heads and had no problems at all, its pods that i have had trouble with and so have thousands of others, its well documented. The stock airbox is even better with the replacement K&N filter and when set up correctly suffers none of the problems associated with pods. I have seen plenty of other bikes that do work well with pods but the Honda 4 runs better with the airbox. I am going to run fuel injection on my 1000cc/4 K2 and am using a modified stock airbox, i am also going to buy one of Tintops filters for my other 970cc F1 build but need to find stacks that work with the RS34 Mikuni's first.

[dave500]

the question is whats the best option?,you have nothing on there now,no mention of engine mods so go with the stock set up,even with mods.

[CafeWild34]

Thanks for all the replies I really appreciate it. I feel like I learned alot. I ordered a stock air filter till I can afford one of those Tintop setups because tthey look bad ass and there seems to be alot of good tthings said about them. Thanks again!

[dtmmil]

Hey retrorocket, question for you, still wondering about the tintop setup in the rain, does it get wet, or does it repel water? And you say you have run pods and had troubles, have you ever tried stacks? The trouble with pods is the reason I run stacks. And I know of a guy from canada that put fuel injection on his cb750, he used a gsxr throttle body setup, its a pretty cool setup.

And I am not so much concerned about how much airflow, not enough to start doing mathmatical equations, but I know I had to jet up with them, and they look way better to me then the stock airbox. My bike is the one in my avatar, there is no way I am putting a stock airbox back in it.

[TicoCafe]

Most of us prefer small and sexy to big and ugly, especially when it comes to women. But like women, small and sexy air "filters" often create more problems than they solve. And they usually can't cook. If the appearance is what's most important to you, then you'll be choosing to deal with the unintended consequences... Stu

LOL... I will have to agree to that!!!

[Retro Rocket]

Hey retrorocket, question for you, still wondering about the tintop setup in the rain, does it get wet, or does it repel water? And you say you have run pods and had troubles, have you ever tried stacks? The trouble with pods is the reason I run stacks. And I know of a guy from canada that put fuel injection on his cb750, he used a gsxr throttle body setup, its a pretty cool setup.

And I am not so much concerned about how much airflow, not enough to start doing mathmatical equations, but I know I had to jet up with them, and they look way better to me then the stock airbox. My bike is the one in my avatar, there is no way I am putting a stock airbox back in it.

The only time i would use unfiltered stacks is at the track, yes i have used stacks but i value my expensive internals more than to run without filters. Not to sure about TT's set up in the rain but these days that doesn't worry me because i have no need to ride in the rain, and its more likely to suck moisture in when standing because your knees and airflow keep the rain off them whilst you are moving. I build performance bikes for myself and always source the best available parts to make that happen, carillo rods, heavy duty primary chains, back cut gearboxes and everything else, most pods are crap and are a total compromise, form over function but i can tell you that TT's filter on a hot 836 with big ports and all the gear , performed faultlessly.

[jawntybull]

I've had a problem with unburnt fuel smoke on the highway for a few weeks and eventually solved it today; the fix included dropping the jet sizes from 115s to 110s and removing the air filter. When I put the airfilter back in it starts to smoke again (run rich) but not as badly as it was.

This tells me the filter has quite a big effect on the carbs, and certainly has to be matched with the right jetting. If you go stock you just follow the stock parameters, but in my case I had carbs from the F model on a K7 bike.

The filter is HiFlo and I wonder if its not that good quality. Any comments on these filters?

Also, I want to go back to having a filter and expect to have to drop the main jets a size or two at the same time - any experience with how many jet sizes a typically filter represents?

[Danno]

I have owned my cb 550 for 27 years and in all that time the only thing that i have found makes the bike run right is the stock airbox you can get close with other setups but most of them make the flat spot that they all have more prominent and then there is the intake noise that other systems have I am not a purist like many others on this site but in this case I don't think you can do better than the stock airbox these carbs like undisturbed consistent air draw with a little resistence