Question aobut high speed wiggle

[ralnsplder]

Today i took the bike out to about 170 and I noticed that everytime I shifted up, the bike would have some wiggle in the rearend. it would only do it for a split second. I do not use clutch when shifting and I run it up to about 11500 rpm befor shifting. Is the wiggle just caused by me burping the gas for a second then getting right back on it hard? It has never done this befor that I have noticed. any help would be appreciated. thanks.

 

[thrasherfox]

Your kidding right? you don't know what that is? you got to be kidding?

If you are not kidding then slow it down bro, you are going to kill yourself.

The best I can tell, your back tire is breaking lose, mine does it when I take it to high rpm's and shift.

I past some cars one day, I down shifted to second and nailed it, hit about 11000 rpm and slammed it into second and my back tire broke lose and fished tailed as I was passing the cars.. Didn't try to do it.. it just did it..

Must of looked kind of freaky when I did it..

Anyway, that sounds to me like what you are experiencing. if you are shifting at that high of an RPM and slamming into the next gear it is more than likely your back tire just breaking lose

 

[ralnsplder]

I don't think it is the tire breaking loose at 160 while shifting into 5th. I have ridden a lot harder at other times and not had this problem. It isn't like im in second as you said you were. I was in 4th going to 5th and it was still doing it. My bike is completely stock other then TRE. so it isn't like i have tons oh HP added to it to cause it to all of a sudden start breaking loose. I don't think a stock busa could break a tire loose in a 4th to 5th gear change doing the speed I was doing. I've been riding sportbikes for about 14 yrs and have never had this happen the way it did today. I also live in hawaii and it is about 77 degrees today. Tires should be sticking well.

 

[thrasherfox]

Today i took the bike out to about 170 and I noticed that everytime I shifted up, the bike would have some wiggle in the rearend. it would only do it for a split second. I do not use clutch when shifting and I run it up to about 11500 rpm befor shifting. Is the wiggle just caused by me burping the gas for a second then getting right back on it hard? It has never done this befor that I have noticed. any help would be appreciated. thanks.

Hmmm I don't have a clue then.... you said it wobbles huh? only shifting gears?

And sorry but if you read your initial post, all you stated pretty much was you did 170, you didn't mention what gear, what speed it was happening in. And you said EVERYTIME you shifted, so I was assuming it was happening in all gears, or more than a few gears at any rate.

The only other thing that comes to mind is check the rim, check the hub, did you have the rim off for anything? If you did maybe when it was put back on something happened.

Good luck. I am out of guesses..

 

[ralnsplder]

I only noticed it in the upper gears. No wheel hasent been off. Chain was adjusted slightly but I moved both sides back sam amount of turns and even measured it out to make sure aligned. Well hopefully someone will know what causes it, I might go out again later see if it happens again.

Thanks for the help though.

 

[jamesnismo]

it may just be a little weight change when you switch gears.... enough to upset the suspension a tad to get a little wiggle. how do you have the suspension set up? how much do you weigh? at 170 it doesn't take much to get the bike to wiggle.

 

[ralnsplder]

bike is set up stock and I weigh about 200. Didn't think suspension was a concern since I have done that speed befor without the wiggle. If the rear tire was just a hair out of allignment would this cause it to wiggle in the high rpm gear changes? I haven't removed the wheel but the chain has been adjusted.

 

[clrwtrbusa]

How many miles on your tires? Mine developed a wiggle with 2000 miles on the front tire. Part of it is the second you shift, you load your front suspension and then unload it when accelerating. Replace the stock POS steering dampner and most of it will go away

 

[Revlis]

Um you might also try relaxing a bit on your bike. I am willing to bet that your kinda pumped up at the high speeds, your kinda hammering them gears and translating that motion right into the chassis via clenched glutes thights and especially upper body. It's important to stay kinda loose and floppy while riding either in the twisties or straight at high speed.... Having a death grip on the controls can cause a weave N wiggle, so try it again and just concentrate on staying loose. Also before you go yeah.. Check your tire PSI and make certain you don't have any cupping or other odd wear going on.

 

[ralnsplder]

Thanks Rev I'll try that