The LC4 engine is notorious for rattling and jerking back and forth due to poor low-end flywheel inertia and I've had a couple of wee moments where the bike just dies during pull away, sometimes resulting in a drop when you're in technical terrain.
Although having the default BST carb serviced and dyno tuned helped a bit towards improving this slightly this still happened often enough adding unnecessary effort and required energy for outrides.
Between the various mods available for these bikes I came across the heavier flywheel mod here:
http://www.altmann.haan.de/ktm_lc4_flywheel/
Had a buddy manufacture one for me and fitted it over the weekend, what a difference!
It sucks now having to kickstart every time but improved linear power output and halfing the vibrations definitely make it worth the sacrifice. The initial (short) test run was absolutely awesome, while around 25km/h I geared up to 4th and instead of a jerky rattling engine there was enough inertia to keep it going smoothly and still accelerate.
Can't wait to take it out for a proper offroad session to test it out.
So I'm curious, has any other 640 owners tried the altmann mod and what your experience/opinion is?
Although having the default BST carb serviced and dyno tuned helped a bit towards improving this slightly this still happened often enough adding unnecessary effort and required energy for outrides.
Between the various mods available for these bikes I came across the heavier flywheel mod here:
http://www.altmann.haan.de/ktm_lc4_flywheel/
Had a buddy manufacture one for me and fitted it over the weekend, what a difference!
It sucks now having to kickstart every time but improved linear power output and halfing the vibrations definitely make it worth the sacrifice. The initial (short) test run was absolutely awesome, while around 25km/h I geared up to 4th and instead of a jerky rattling engine there was enough inertia to keep it going smoothly and still accelerate.
Can't wait to take it out for a proper offroad session to test it out.
So I'm curious, has any other 640 owners tried the altmann mod and what your experience/opinion is?
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