Bike has super aggressive shakes during idle
 

Hi everyone, I just got my new Hawk 250 to start today and whenever I start it and let it idle it shakes and vibrates. A lot. I'm new to motorcycles and dirt bikes in general so I'm not sure if this is normal or not. If it is an issue and I'm not just being nervous how should I go about fixing this? If you can, please explain it as simply as possible, my knowledge on the subject isn't very great



Thanks,
GoldenBoy

I'm not saying there's nothing wrong with your motor -- I'd have to be there to see it for myself -- but it well may be there's nothing wrong with it. A single-cylinder engine is by its nature unbalanced, and although various mechanical features and contrivances serve to reduce vibration in some motors, usually they are going to shake at idle and buzz at speed. On the other hand, something like a 6-cylinder Honda Gold Wing can idle so smoothly you almost have to touch it to make sure it's running. There's a reason single-cylinder engines are often called "thumpers".

Its got a little bit of time before the field I'm practicing on is open so I'm just gonna assume its just my nerves getting to me
Hopefully I don't crash

Update: didn't crash after first ride, and I figured out why the engine kept going nuts. My bike acts as if I'm tugging on the throttle even when I'm not, I think I tightened something on the carb to much. Gonna adjust it and try again

I'm sure its just normal idle or perhaps a slight adjustment needed.. or hmm.. maybe you got "Harley mode" enabled ;)

If it was in Harley mode, it would've leaked a puddle of oil then quit.

I got it started again after some adjustments and nothing changed, ended up crashing this time. The bike is acting like the throttle is being pulled but its not, its going near full speed whenever its in first gear, is there any way to change that? I don't know about anyone else but I'd rather not go flying off into the distance from 0-12 in 1.3 seconds


Thanks again

Is the choke on?

Yes, full choke. I've tried it at all three choke settings and it does the same thing regardless, I think something at the throttle itself isn't right. I could definitely be wrong though

Possible problem is that all slack has ben taken out of the throttle cable. Ensure that there is a little wiggle room.

Sounds like you have the idle set way too high. If the idle speed screw does nothing than more than like likely there is not enough slack in the throttle cable or carb slide is in backwards.

The throttle slide might be in backwards

Okay guys, I finally figured it out

I had bought a third party carb to replace the sock one which I heard was junk. On the third party carb there was a little needle that was stopping the slide from going all the way down. It took me a pretty long time to notice this despite it being a really important detail. It still doesn't run perfectly but at least its better, thanks again everyone for all the help!

Not sure if this will help you or not but my father's hawk with 10 miles on it, had this issue and I discovered that there was not enough slack on my throttle cable and whenever I turned left it overstressed the cable. The throttle cable was actually coming out of the carb at about a 15 degree angle.

I was able to add more slack by shifting the cable to the front side of the cluster, closer to the key. The cable now comes straight out of the carb and the throttle is smooth as butter.

The idle is sporadic, smooth one minute and shaky the next. My father ordered a new carb but it won't be here for about 2 weeks. I assume that will be the resolve we are looking for.

Goldenboy are you able to upload a video to youtube of your engine idling after warm up?

Goldenboy are you able to upload a video to youtube of your engine idling after warm up?[/QUOTE]

I'll get one tomorrow at around 3:30 pm MST when the field I practice in is free again

I have no idea what happened with the quote thing but its not important right now

one of your motor mount bolts fell out.