there is a 2510 filter which works well. If one is worried about the fitment, I guess you could always LOOK in the online K&N catalogue and check all the dimensions. The 2510 is on a 20 degree angle like the 1770, but the filter is tapered. They both have a long flange on them which can be shortened by approx 40mm to lower the top of the filter below the line of the tank. They are also( and this seems important) cheaper than 4040. I have achieved 250hp with 1770's so I don't think most will be held back by them or the 2510 for that matter. If you wish to retain the bearclaw then Hanso is correct, the ramair works quite well.