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KTM 525 EXC Valve sound

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Hey folks I was looking at a KTM 525 EXC today and I am not familiar with the rfs engine. Ive heard tappy valves before and the top end sounded quite a bit louder than tappy valves. So question to you all is how much top end noise do these bikes make on average? My LC4 wasnt very loud at all.

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they are very loud

thanks this is reassuring. it didnt sound like the cam chain it sounded like the valves..the bike has been rebuilt already once on the top end with 225 hours. Im just not used to hearing so much action on a top end. i normally ride dual sports.

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ive only had mine for a few weeks and i was really worried about the noise. i changed the cam bearings, cam chain, and checked/adjusted the valves but the noise was still there!!! also the clutch is noisy and if you have a bash plate it amplifies the sound and makes it sound way worse. from what i have read/heard most large single cylinder bikes make a fair bit of noise in the top end but the rfs engines are extra loud

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thanks this is reassuring. it didnt sound like the cam chain it sounded like the valves..the bike has been rebuilt already once on the top end with 225 hours. Im just not used to hearing so much action on a top end. i normally ride dual sports.

Thay can be tappy if they are more than .005" in clearance. Not too big a deal for low speed riding. Better to make sure they are at .005" when stretching the cable.

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They sound like a bag of hammers being thrown down the stairs. Music to my ears.

Go to KTMtalk.com and search the rfs section. Lots of discussion there.

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They sound like a bag of hammers being thrown down the stairs. Music to my ears.

Go to KTMtalk.com and search the rfs section. Lots of discussion there.

Yep, they're noisy! Scared the hell out of me the first time I rode mine...

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i have a 01 520exc. the rfs is short for "racing four stroke" and i beleive they started in 00 and went up until 08(?) not sure. then they changed to something else. so you'd definately have an rfs engine.

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