Best race air filter?

Whats the best air filter out there, need to order one up this week? K&N, Pipercross, BMC???

Have both a BMC and a Pipercross one on each bike and there is next to no difference on the dyno, the BMC one is slightly better made IMO, seems higher quality than the Pipercross. Have never seen a K&N in the flesh. I beleive you are building a hot SV / 700CC version, that is a different kettle of fish and there maybe differences as you move away from a standard engine. Steve Jordan will know what is the best choice for a tuned SV.

Originally Posted by RGV250ads

Have both a BMC and a Pipercross one on each bike and there is next to no difference on the dyno, the BMC one is slightly better made IMO, seems higher quality than the Pipercross. Have never seen a K&N in the flesh. I beleive you are building a hot SV / 700CC version, that is a different kettle of fish and there maybe differences as you move away from a standard engine. Steve Jordan will know what is the best choice for a tuned SV.

Orderd a K&N on advise from someone else, Jesus don't be saying I'm building a 700cc, the MCUI will have it stripped at the first meeting after me paying to have it built! I'm not building a 700CC, just putting 645 high compression wisecos and carillo rods into my 650 and having the heads ported.

ah whoops

[Red Herring]

Originally Posted by weecorey

Orderd a K&N on advise from someone else, Jesus don't be saying I'm building a 700cc, the MCUI will have it stripped at the first meeting after me paying to have it built! I'm not building a 700CC, just putting 645 high compression wisecos and carillo rods into my 650 and having the heads ported.

LOL, perhaps if we can "leak" this about mid season they'll strip it for you just about the time you need an inspection. (I'm guessing the old rule about them paying if found to be legit still stands?)

Originally Posted by Red Herring

LOL, perhaps if we can "leak" this about mid season they'll strip it for you just about the time you need an inspection. (I'm guessing the old rule about them paying if found to be legit still stands?)

Im not sure it does sadly as one we built for a lad doing the roads in Ireland got stripped as it was too quick LOL. He had to send it back here to be put back together and he wasnt offered any costs!. Not sure what club etc though.

TBH The BMC/Pipercross and Standard all flow very similar. Its only when you get into fitting a pure race filter do you see any difference in flow and then you have to mod the airbox to make it work as the stock airbox is quite restrictive. The minitwin I had in 2005 got dyno checked at Cadwell and was found to be 72.8bhp (was a good bike that one!) and I got asked to put the stock filter in. I did and it made the same LOL. Ok you cant re-create air flow properly on a dyno!.

Std filters though are expensive and arent cleanable.

If they strip you, you have to pay for the rebuild no matter what.

[Red Herring]

In my day, which I admit was a little while ago, you had to lodge a sum of money with the organizer when you protested a fellow competitor. It was one amount for a two stroke, and a bit more for a four. If the protest was found to be in your favour you got the money back, if you called it wrong and the engine was legit the rider got it to go towards putting it back together. Is there nothing like that any more?

hi red, this seems like a much fairer procedure - sort of put your money where your mouth is so to speak before you attempt to lodge a spurious protest which costs nothing - how could we get this changed?. What sort of fee would you suggest?! Anyway this thread is about air filters and I guess there is little to protest about suspect air filters..........maybe airboxes is a more interesting topic or even snorkels...........

Originally Posted by weecorey

If they strip you, you have to pay for the rebuild no matter what.

Not true.

From the MCUI(UC) site:

Please note that in accordance with the General Competition Rules the promoters of any event reserve the right to measure the capacity of any machine. Also the cost of the rebuilding any machine so measured rests with the entrant even if the machine is found to be within the capacity limit for the class.

In this case the bike is stripped by the owner/mechanic and measured by the Technical Steward. It is the responsibility of the owner/mechanic to rebuild the engine. No recompense is given (apart from a gasket)

Originally Posted by Red Herring

In my day, which I admit was a little while ago, you had to lodge a sum of money with the organizer when you protested a fellow competitor. It was one amount for a two stroke, and a bit more for a four. If the protest was found to be in your favour you got the money back, if you called it wrong and the engine was legit the rider got it to go towards putting it back together. Is there nothing like that any more?

This still stands for an OBJECTION.


There will be SV650 stripped at short circuits this year - no question about it. There were several stripped at Road Races during last year.

This is all relating to racing in Ireland only.

Hope that clears up any misunderstandings.