So I have a 2003 Kawasaki ninja 250 that doesn't ride smoothly. It has 8000 miles on it and was salvaged when I got it. A few months ago I had a slight crash on it. It got laid down on the chain side but seemed to not have much damage aside from bent clutch lever and pedal plus some road rash. About a month ago I noticed it seems to bounce as I ride. It's a rhythmic cycle of 3 quick bounces and a pause that speeds up as the bike speeds up, which makes me think it has to be something that's rotating, does that seem like a correct assumption? I lubed the chain thinking it could be a tight spot, then balanced my tires thinking that could be the problem. The tires definitely needed to be balanced and helped some but it's still noticeably there. Before I balanced the tires it was nearly equally noticeable at any speed but now it's much more noticeable at 45 mph rather than higher speeds. It's somewhat more noticeable at slower speeds than higher speeds. I'm thinking the next things I can try are replacing the chain and/or sprockets. A mechanic told me I need to replace them together is this true? I thought I would replace the chain only and see if that's the problem. I felt it for tight spots but there wasn't anything obvious to me. Does anyone have any other ideas of what it could be or what I might try? I'm also wondering if one or both of my wheels got bent in the crash but I find it odd that I didn't notice the bounce until a month or so after my accident. Granted I had to take some time off due to my torn acl but still.. Is there a cheap, easy way to check for a bent wheel? Any other suggestions? Thanks to the troopers who made it through this whole post and for any help or advice!!!
well the fact that your bike has 8,000 miles makes me think it needs valve adjustment if it's never had one. I'd been having a "bouncing" type of thing happen when I was riding. Mine was more at around 60mph. Adjusting the valves isn't too difficult, but it takes quite a while if you do it yourself. I just did mine this past Wednesday and it's been running great since. My bike has 16,000 miles and I bought it with 10,000. I don't think the previous owner had ever adjusted them.
it could be the tires also, but my first guess is the valves. You'll feel like the bike's jerking forward and backward when you're riding.
How old are the tires? If older than 5 years old or show signs of age (cracking, dryness), you might need to replace them.
Is the motion up and down or an oscillation (side-side) in the handlebars?
Have you checked the forks to make sure they function properly?
Is the front axle slightly bent at all?
The motion is up and down, not side to side or a backward and forward surging motion. I can't see anything wrong w the forks, it doesn't pull to one side at all. I don't know how to check the axel for damage. The tires are pretty much brand new but they're shilco brand and needed quite a bit of weight to balance them. A mechanic I talked to said the tires might not actually be round which could also cause this problem..
....The tires are pretty much brand new but they're shilco brand and needed quite a bit of weight to balance them. A mechanic I talked to said the tires might not actually be round which could also cause this problem..
I think you mean Shinko. It is possible for the tire to be out of round as well as being balanced wrong. Too much weight can effect balance as well.
Easy to check. Put the bike on the center stand, have someone hold the back of the bike down, Put a small block under the front wheel (one that barely touches) and rotate the wheel until it touches the block or stops.
Yeah your right I meant shinko. And I looked at the wheels while spinning them and the back tire is obviously not round. The front is close but not quite round either. So I figure that's got to be it. I'm pretty small so I don't think too much weight would be the problem. So I guess I'll just run those until I can afford some new tires and get a better brand this time. I hate to waste these when I just got them even though they suck. But I wonder how dangerous it is to be bouncing down the road lol. Maybe I should just bite the bullet and buy some new tires, but if I get new tires and find out thats not the whole problem it's gonna drive me nuts!! Lol