i've been riding a fixed gear jamis sputnik for a coupla months now and the gearing on it is very high. i havent had the money to have it lowered. but i've been riding it alot and have been going downhills even though it is very hard on account of i cant skid. i have begun to get pain in my knees fir the past 3 weeks. i know i should have the gear lowerred and that the backward pushing is damaging my knees. i just want to know if this slight pain will be permanent because i'm only 16 and dont want it to become a permanent problem for me.