klx300 dual sport (2020+) and klx250s camshafts are the same. klx300r (2020+) camshafts are different. Also klx300r camshafts are the same as ninja z250sl (250cc engine, see attached diagram) which produce 28hp@9700 & 22.5Nm@8200. Sprockets on klx300r and z250sl also same. And these are different (different part numbers) from kls250s and klx300 dual sport. Did anyone figured our if sprockets are actually different (different cam timing?)?

 

According to Keng Engine gears are same!

 

For those who follows:

1. All klx250 (including klx250s, klx250r, klx250E, klx250D, klx250A) have same camshafts. These are also same with 2021+ klx300 dual sport and old (prior to 2007) klx300R. All these have part numbers which cross match. You can find more details in this thread. I've checked service manuals for klx250r, klx250e, klx250d, klx300 and modern klx250(s) EFI. These cams have same duration timing and lift:
   1. Exhaust BBDC 61° - ATDC 19°, , duration 260°
   2. Inlet BTDC 22° - ABDC 62° , duration 264°
   3. Intake Lift 36.246 ∼ 36.354 mm, Exhaust lift 36.246 ∼ 36.354
   4. So exhaust LCA 111° BTDC, intake LCA 110° ATDC and LSA = (111 + 110) / 2 = 110.5°
2. New 2020+ KLX300R camshafts and/or cam gears are different from above. 2020+ klx300R camshafts and gears are identical to Ninja Z250SL (same part numbers). I could not find klx300r service manual, but I found z250sl service manual. Which states following timing and lift:
   1. Exhaust BBDC 63° - ATDC 21°, duration 264°
   2. Inlet BTDC 20° - ABDC 64° , duration 264°
   3. Intake Lift 35.743 ~ 35.857 mm, Exhaust lift 35.743 ~ 35.857
   4. So exhaust LCA 111° BTDC, intake LCA 112° ATDC and LSA = (111 + 112) / 2 = 111.5°

Lower lift is especially surprising. Wider LSA make sense for z250sl which makes top power at 9700rpm, but not so much for klx300r which should have bottom torque.
Also since timings vary very slightly from klx250 I would suspect cam gears are same as klx250, but only camshafts are slightly different.

 

This is fascinating information. Thanks for compiling it.

For reference, I dyno tested my 2021 KLX300SM

HP 25.0 @ 9,100 RPM
TQ 16.5 @ 7,600 RPM

This was bone stock with a slip on exhaust as the only mod.

 

Camshafts article with all the KLX300R(2020+) and KLX250/300 specs - https://planetklx2.netlify.app/docs/engine/camshafts/
@RaceGass you've been correct - Keng cams are not KLX300R cams. Their base (how they are attached to timing gear) is the same as in KLX250 and different from KLX300R.

And detailed video comparison:

 

Thanks for clearing up the cam manufacturer question. The cam gears being different helps make the decision to go with Kengs cams an easy one, price wise also.

 

Update - 2020+ klx300, 2020+ klx300R and z250sl cams are the same (the only difference is KACR in klx300. why??) -