what causes a bikes rear to swing out when jumping

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#1
sometimes, when i do a jump, the back end of my bike wants to go out to side. Could it be from not enough air in rear tire? or maybe too much?

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89 yz 125
79 bultaco pursang
 

High Lord Gomer

Poked with Sticks
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#2
Ruts or bumps on the takeoff of the jump can kick the back end out. A suspension rebounding too much can exaggerate the problem. Have you had your shock serviced lately?

I was having a problem with the back end kicking around and it was badly worn swingarm bearings that let the entire swingarm cock sideways.

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#4
I've had this problem. But it was my rear tire slipping to the side when the front just came off. Maybe i was putting to much weight on one peg or something.

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#5
When it happens to me (other than from a rut or bump on the jump face) it is because I am slightly leaning or weighting one side of the bike.


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Reeko
(Now a Red Rider)
01CR250 (Me)
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nikki

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#6
It also happens if you aren't square to the jump when you go off of the face - like if you're still kinda turning...

Or on really windy days...

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'01 YZ 125 - #32
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#7
I agree with nikki, if you are riding tight stuff (supercross/arenacross) it happens all the time, because you can still be sideways from accelerating out of the preceding corner. I have found that it works best to just pull back with your leg, and not worry to much about the landing, because once both tires hit, you will be strait again. just don't over-correct when you land or it can get ugly! ;)

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Brandon YZ 250
 
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#8
i ahve also heard that that happens if your rear axel is not strait. Make sure the chain adjust bolt is the same length on both sides. And make sure you are strait coming out of the turns also, i broke my wrist that way. It was real muddy and i didn't get out of the turn strait when i hit the jump.

-Brent

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00 CR250
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#9
I had this happen, it was from a flat tire!! That and accelerating on the face of the jump. Oh yeah, this jump was very narrow, so half the time it would kick me sideways.

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The Original Speedster
1985 XR100R
1978 XL250S