But it would be nice to know if the stock restrictor plate can be removed as a small DIY mod for a small HP gain. Or at least knowing that removing it won't mess up the stock fuelling.
But it would be nice to know if the stock restrictor plate can be removed as a small DIY mod for a small HP gain. Or at least knowing that removing it won't mess up the stock fuelling.
True! I noticed you posted up on that thread too. Didn't a member here just pop out the rivets to remove that plate on the oem filter instead of cut it?!? At least with the BMC, it's interchangeable.
I think once you get a full system, PCIII and a filter like the BMC you can have it custom mapped to accomodate the more air flow.
I popped the rivets and removed mine. As I said before it almost felt flatter though I suspected it might have just cleaned up some delivery. Well not one to trust common sense we took to the track and did roll ons, mine with addition removed and my team mate with the thing still in place. Otherwise identical setup with Leo exhaust and no fuel mapping. Mine was quicker and was consistantly pulling a gap through the rev range for two runs.
We then pitted and removed the plate from the other bike and did the run again and there was nothing in it, bikes pulled exactly the same.
Verdict, there are definitely gains in taking it out, even if the bike does feel flatter with it out. What its there for? Who knows. Mate of mine spoke to a Yamaha Techy in Qatar and this chap said you may lose some mid range with it gone though I found the mid range was probably better and hence you lose the in rush of power which makes the bike feel very fast. There will be bigger gains with mapping sorted out too, our bikes are throwing huge flames out the exhaust on downshifts, always a sign of a bike running quite lean.
I popped the rivets and removed mine. As I said before it almost felt flatter though I suspected it might have just cleaned up some delivery. Well not one to trust common sense we took to the track and did roll ons, mine with addition removed and my team mate with the thing still in place. Otherwise identical setup with Leo exhaust and no fuel mapping. Mine was quicker and was consistantly pulling a gap through the rev range for two runs.
We then pitted and removed the plate from the other bike and did the run again and there was nothing in it, bikes pulled exactly the same.
Verdict, there are definitely gains in taking it out, even if the bike does feel flatter with it out. What its there for? Who knows. Mate of mine spoke to a Yamaha Techy in Qatar and this chap said you may lose some mid range with it gone though I found the mid range was probably better and hence you lose the in rush of power which makes the bike feel very fast. There will be bigger gains with mapping sorted out too, our bikes are throwing huge flames out the exhaust on downshifts, always a sign of a bike running quite lean.
Thanks for the info. It would be nice to have dyno proven results. I think I might try this mod later after I've gotten used to the fuelling on the stock bike.
Btw, if your bike is spitting flames, it means its running rich.
Yes, richness is a common misconception but it's not. When a bike spits flames you'll cure the problem by going richer, hence a lean condition. Pretty easy to justify this because a race pipe causes flames with the same fuel being put in by the ECU. If this was caused by a rich condition that would mean a lower air fuel ratio and hence less air for the same fuel. You make more power by getting more air in to the engine so if a race pipe causes a rich condition then its simply not working.
I suppose people think too much fuel when they see fire because fuel burns but remember it's the oxygen thats actually burning when mixed at 14.7:1 ratio with fuel. The 13.2:1 ratio that we all tune for is not the optimal ratio for power but this has been emperically found to be the ratio at which with the mixing found in the engine you'll get the highest concentration of air molecules combined at that magical 14.7:1 stochiometric ratio with fuel and hence the greatest power output. Now as I understand it lean conditions lead to more oxygen coming out the exhaust and its this oxygen combined with engine byproducts that causes the flames on roll off.
i did mine this weekend and took it up to the mountains and it felt alot better low end still feels lousy but did feel flatter and i am happy with the results
Linear Mode
