Air filter & poor high speed running

Paul
Your welcome
Remember to wash all the oil out before using it
Those Uni-Filters strangle the top end terribly.

 
Red mabe that was the reason why my 3C would cough and suddenly slow when I wanted it to rev over 6000 rpm for longer than a couple of minutes on the Snowy run,did it 3 times on the Imlay Road,I am going to leave it as is,fully oiled till I have a run on Steves LM1 then clean the Unifuilter and see what it does.
 
Vince,
You would be better off washing it first before you go onto the LM1.
Waste of time otherwise and Steve's spare time is limited as you know.
Standard Uni-Filter acts like a rev limiter, bike runs out of air at ~ 5,500 rpm

I don't use them anymore myself preferring the air con gauze discussed before in other threads.

Tchau
Red
 
Just a bit consered with a clean filter it might be too lean,the way its going it will probably be after Christmas before I even ping him and even then all I want to do is get a quick baseline without swapping brass,kinda picked up there is some SFC racing action coming up very soon.Not to meanion the NSW club Christmas party at his place,got to prioritise,racing and party's come first.
 
my 3C would cough and suddenly slow when I wanted it to rev over 6000 rpm for longer than a couple of minutes
Click to expand...

...could also be fuel starvation.  Found this on my '80 Jota -especially when fuel was low in the tank.  Fixed by using larger float needle valves (300) and an RGS fuel manifold.  Maybe crap in the fuel tap/banjo filters too?
 
I am running 38mm Kehan CV carbs and a large Home in more ways than one made airbox,its going great except for the extended top end stuff,don't want any melted piston problems so I will err on the side of safety
 
redax5 said:
Paul
Your welcome
Remember to wash all the oil out before using it
Those Uni-Filters strangle the top end terribly.
Click to expand...

have done so mate-will test on weekend-may look into aircon mesh as well


cheers paul
 
Vince, no concerns on the melted piston tops, your pistons crowns are ceramic coated
give it the berries

Red
 
For a cheap and cheerfull test I am guna pull the element and do a quick spin around the block,it will either be the Carl Expressway or the Bradfield Hwy over the Harbour Bridge,might be 2 and 3rd gear at 6000rpm plus, the holiday double demerit on licanse points starts for the holidays soon thought
 
Vince said:
For a cheap and cheerfull test I am guna pull the element and do a quick spin around the block,it will either be the Carl Expressway or the Bradfield Hwy over the Harbour Bridge,might be 2 and 3rd gear at 6000rpm plus, the holiday double demerit on licanse points starts for the holidays soon thought
Click to expand...

No no no no

All it takes is one little piece of hard shit....kaplowie!!!!! Goodbye Valve, goodbye valve seat, goodbye rings and liner or perhaps goodbye ceramic coated piston.
 
Wow. That is some determined little piece of hard shit............

Pull the filter but remember to hang on tight, the old things go quite well when they get a bit of air.  :D


      Keith.
         
 
Davo said:
No no no no

All it takes is one little piece of hard shit....kaplowie!!!!! Goodbye Valve, goodbye valve seat, goodbye rings and liner or perhaps goodbye ceramic coated piston.
Click to expand...

:o

My 3C hasn't seen an air filter since I bought it in 1980, the engine's been all over Europe in all kinds of weather conditions.  Present pistons are now 20years/70000km old, still running strong.

As long as one doesn't venture too far off from civilisations' paved roads, I don't see a filter as being really necessary.  Maybe for a Sahara or Nullabor crossing..... 8)

piet
 
When I installed one of those foam filters on my RGS "1200" I spent hours and hours chasing a top end starvation issue, drove me nuts..... Put in bigger flat valves, even cross drilled the float valves, adjusted the floats over and over, tried everything I could think off.

Solution? Chuck the foam filter as far across the garage as you can and use something that breathes - I cut uo a flat K& N filter intended for a Honda Valkyrie, no top end starvation, instant fix..... I wouln't even give someone the foam filter, wouldn't want to inflict them with the problem, I threw mine out!

Paul LeClair

 
OK, so maybe that was a bit extreme. And maybe I spent too much time riding in the dirt. But there is no way I would run an engine I had any love for without an air filter, especially the way the roads are here in West Oz.

Oh, and I have seen the end result of a bike that swallowed a piece of gravel, not pretty.
 
Running 38mm Mikuni CV's on my RGS and a Uni Filter well washed out.
No problems at the top end, runs cleanly all the way through the rev range.
Used the LM2 to set up, affective and easy to use, a bit of a problem with intermittent tacho pickup but working last time I tried.
Also moved to a 19/38 final drive.

Ran the bike for many years in South Africa with 36mm Dellortos and no filters and no problems at all.
Added the Uni when in NZ with the road works with the stone chips and and dust.
Its amazing where the stone chips get to, found several around the plugs, lift out with tweezers before removing plugs.
 

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I thought I should also confirm what Red and others have said. My engine used to hit the wall at 5500 rpm even without a filter in the airbox. When I fitted some pods from Red she flys right through to redline.
Cheers John
 
100kms without filter and 200kms with the uni filter-a bees dick less up top-i dont run up there much anyway-she pulls clean now in top gear from low revs no probs-you beauty
 
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