exhaust & breather/oil catch tank helping hand time

[Sonny Jim]

hi im looking for a bit of advice if anyone can help, iv got a 1.3 sr running on R1 bike carbs . the exhaust that is on now is past it so im looking for a new one to go from the manifold just not sure what is available and what you recommend that will sound the best and keep compression, i could get a stainless steel badboy made up from a local exhaust maker but he would charge in the region of £300-400 so thats a no go..
also im after a catch tank with a breather but there isnt any space for it from what i can make out so just wondering what methods people have used that havnt caused any problems OR a catch tank that is small enough to fit somewhere lol

cheers dude's !!

[phazer]

My breather is a bit naughty and runs down to the tie bar where it vents to the road. No tank needed.

[MK1_Ben]

My breather is routed into the side of an Energy drink can (circular cut out hole with a washer). Small and out of the way, still vents into the atmosphere but stops oil mist going everywhere :)

Poor quality photo:

http://i1000.photobucket.com/albums/af126/bsrally/Photo037-2.jpg

[phazer]

Yeah probably best to catch it if yours is breathing heavily. Might get one drip in the garage after a hard run on mine so happy to run without.

[MK1_Ben]

When you're running a tappy 120k mile carbed 8V, it likes spitting oil out the breather everytime you look at it :)

[phazer]

It just likes to share lol

[mk1nova_rich]

Use a mild steel Sportex system for £110

[peester]

One of the cheapest smallest catch tanks with a breather outlet (on top) just buy a breather filter and jam it on.
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=200387669382&ssPageName=STRK:MEWAX:IT

I was and still am thinking of getting one; i even did a decent template to see how it would look/fit against the firewall.. lol
http://img.photobucket.com/albums/v11/peester/IMG00137-20110213-1529.jpg
Though if/when i actually get round to buying and fitting; ill position it lower down, bit more hidden i think..

[Mike]

Ashley Exhaust system & a Sportex manifold is what Id do.

[mk1nova_rich]

remember not to put the catch tank too low down, it should be line with the top of the engine...

[peester]

its not under pressure or feeding back into sump/engine, so should be fine.

[MK1_Ben]

If it's too low it will create a siphoning effect with the change in pressure.

However I believe it has to be lower than the initial breather outlet, which is fairly low down anyway.

[Mike]

However I believe it has to be lower than the initial breather outlet, which is fairly low down anyway.

Liquid (amongst other things) always finds it lowest point. It'll always go down, not up, down, always down.

[mk1nova_rich]

its not under pressure or feeding back into sump/engine, so should be fine.

As Mike says once the vapour collects into liquid it needs to drain back into the engine which it wont do if the outlet on the catch tank is lower than the outlet on the engine

[peester]

but catch tanks dont have to drain back into engine..
So collecting the excess vented from top of engine doesnt need the catch tank higher than the engine; as it travels down..?

[Mike]

Rich, the inlet of the catch tank needs to be lower then the outlet on the engine else it wont drain into it.

[phazer]

Does it actually matter if it drains? The engine shouldn't be breathing that much oil if it's healthy. The small amount of oil you do get comes from the vapour condensating on the inside of the tubing or tank. The pressure of further vapour being produced will push any large quantity of oil sitting in the pipe into the catch tank.

Most breathers get fed back into the throttle for the vapour to go through the combustion cycle again in OEM setups. There isn't anything harmful to the engine weather it drains back into it, gets fed back through or vents to atmosphere (though in this case you need to ensure if doesn't get into the cabin as it is not good for you at all!)

[Sonny Jim]

cool cheers for that people some good advice there. its not tappety or breathing oil heavily, maybe a drop after a good drive , has done nearly 117 thou miles though. think i'll leave the catch tank for now until iv got the sausage filter on see what it looks like after that ! :)