Unhappy with the ride.

[Zabrow187]

Not me, my dad.

He recently purchased a 08 KTM 450 EXCR Sumo, after riding it for two weeks he told me today that he was unhappy with the way the bike rides. He likes to explore on his bikes, and not always be on the pipe. His complaint with the KTM is that the front wheel "bounces" in the low to mid RPM ranges. So if he is doing 45 in 4th gear the wheel feels as if it is, noticeably, being pushed towards the bike and causing an unpleasant ride.

He described the feeling specifically as a harmonic causing shifting through the front end

He has had the front wheel balanced, I suggested he makes sure the wheel is true. He said he is going to also check the steering head bearings to make sure they are OK.

Do you all have any suggestions? Have you ever experienced anything similar?

[fishpost19]

Have you watched him ride? Sounds a bit to me like he's lugging the bike too much, like he is a gear too high and the engine is loaded too much. Is it his first modern single cylinder? He may be used to older big bore singles which love to punt along at low revs, whereas newer 450s need to be ridden in mid to high revs. What gearing is he running? Just trying to rule out operator error, there are plenty of times where the problem is between the handlebars and the footpegs!

If not, I'd say what you've already suggested - wheel balance, check for runout/buckling, and steering head bearings.

Have you ridden the bike and experienced the problem? He may not be used to the different riding style and power curve of a single cylinder

[Skully25]

if he geared it long enough riding 45 in 4th is definately lugging it...

[HPIguy]

What kind of shape is the suspension in? When was the last time the forks were serviced? Lugging it may very well be the case, but proper suspension set up (setting the sag, and making sure everything is in good working order) makes a huge difference.

[Zabrow187]

The suspension was recently serviced, so it is in good condition. I don't know if my dad has adjusted any of the settings yet.

I have ridden the bike once and it was smooth when I rode it, but I may have been keeping it in in a higher RPM range than he does. From my experience riding with him, he does prefer to keep the revs low when the riding isn't "spirited".

This is not his first newer big bore single, but it may be his most recent big bore street single so maybe he isn't used to riding it at a higher RPM range.

[Rider52]

Hes lugging it guaranteed. Tell him whenever it does that to downshift once, its not designed to run at that low of rpm its a real bike not a pickup truck.