Engine Noise

[Mike Horton]

My 73 Jackpiner (black motor)has a new engine noise that doesn't sound quite right. At idle in neutral or just off idle when riding it sounds like the motor is crushing rocks in the crankcase area. Also when idling in neutral if you pull in the clutch the noise for the most part goes away. I know KTM's motors tend to have some engine noise (my 200 EXC has  similar sounds), but this just started after almost a year of riding. By the way, the motor is running great and trans and clutch are working perfectly.  Anyone have any ideas ?

Thanks Mike

[tmc3c]

Mike,My 250 was making some awful sounds this past week but I think mine is fuel related "water in gas" I assume.Have you been running the same fuel?Are you getting any shavings when you drain the gear box?



Thomas Carmichael


1970 125 Six Day
1976 250 Hare Scrambler

[hrbay]

Hey Mike, I would check the flywheel and backing for tightness, and possibly the clutch for broken springs, b4 going deeper. Sounds like a crank line play that is eliminated by clutch pull.

GC

[Rain Man]

hhm a rock crusher 175 !!      does the noise get louder the longer you ride it? or does it always stay the same ..  Sounds like your clutch plates could be rattling against the clutch basket. but then again the coolong fins on the cylinder do get kinda loud.
 The clutch does make a distinct noise. when engaged and disengaged.

  never the less, these big finned motors do shake rattle and roll

Raymond
 Down East Pentons

[Rain Man]

After thinking and reading about this for awhile, it also could be a lean mixture ( why would it change all of a sudden ? ) and the timing off.  Thats some of the symtons.  Also look at the plug, and see what it indicates!  Mine are usually covered in oil from riding so slow [8D]

Raymond
 Down East Pentons

[Dobber]

Mike I also have a 73 jakcpiner (Black motor) Another thing that might come into play is the splines on the main shaft & the one the clutch is on. I have seen the splines get worn & the gears on the shaft will have a lot of back lash that will make the noise you desribed. This is unlikely but worth a look. I agree it is probably the clutch discs or the basket. hope this helps.

Shaun (Dobber)

73 Jackpiner