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Discussion Starter #1
Just got some new Michelin rp4s. After the stock tires I wanted something that would last longer. Anyways I like the tires and they wear great. But I ha e a speed wobble right around 110mph. I rebalanced the tires at a different place just to make sure the balance was true. The wobble is inconsistent not the same all the time and bumpy roads brings it out more. Also if I'm in the throttle in 4th or 5th it's more pronounced vs slow and steady 6th gear. But the bottom line is I has a wobble where as I didn't have one before. Pressure is 32 front and 35 rear. Any advice would be greatly appreciated, ty.
 

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Front of the bike is light, you're probably light too. Don't hold the bars tight. Keep your weight forward, and maybe a steering stabilizer
 

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Mine does it too in the stock tires. And I'm still a new rider I just know to back off when it starts until I learn how to manage it. I laid my first bike down after hitting some railroad tracks at about a 40 degree and the bike went into a tank slapper (I feel the term speed wobble isn't accurate since I was only going about 35). I try to stay away from that wobble lol
 

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Hi , Use the search to fix wobble. The answers are out there


Sent from far outer space
 

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those tire pressures are too low for that speed

if you wanna be a speed demon run stock psi

i run 34 front 36 rear and not always but sometimes under hard accel my front will start wobbling
 

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Discussion Starter #8
I'll try the stock pressure and hopefully that might be the cure or help more. I'm not riding 110 everywhere also but with the wobble I find myself testing the bike more. I guess half heartedly hoping it will some how go away on its own. Thanks for the help all.
 

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It most likely has nothing to do with the new tires or the balancing--too low tire pressure, minute undulations in the road surface, cross winds, and the light and twitchy nature of this front end at 100+ mph(or a combination of these factors) have more to do with it than your tire choice. And if you're on the throttle at speed, the weight distribution to the rear is more pronounced, compressing the shock and lightening the front end. You didn't indicate whether you had a screen on it, which with some screens make it more unstable. Adjust your tire pressure and then experiment with it on a different road and see if the problem persists...
 

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I wouldn't put 42PSI in the rear. Not sure about the wobble, but I'd rather hold traction in the corners than be more stable at deadly speeds, and that's if you accept the premise of tire pressure being the cause of the wobble. You want your tires to be around 36-38psi warmed up on the street.
 

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Low tire pressure is not the issue. I run 30 front and back.

You need to tell us the set up on your bike.

Windscreen? Forks lowered? ZX10 shock?

The bike is somewhat twitchy in stock trim but the before mentioned items can make it more pronounced.

I am running a medium size windscreen and have a Penske shock that has raised up the back a bit. My bike sometimes feels like it wants to wobble but actually never has.

For me I rarely go north of 100 as the bike feels twitchy above that speed.

If I really feel the need for speed I jump on my Concours 14. It is solid at any speed.
 

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Discussion Starter #12
Everthing is stock except a yamaha cowl and I had that put on when I bought the bike. The strange thing is before the tire change I never once had a speed wobble.
 

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I had horrible wobble problems with my Ninja. I replaced the steering head bearings, checked wheel alignment, etc and nothing had a major improvement. In the end I had to raise the front end 1/2" and it was gone for good.

I would check with the string or straight edge method to makes sure the rear tire was aligned properly. I think Projectslocus may be right, from your description it sounds like the problem occurs when less weight is on the front end. If the rear tire is aligned properly I would try either lifting the rear end by adjusting the spring tension or by lowering the front end (raising the fork tubes in the triple) 1/4" and see if the change in height helps. Be very careful riding after you make a height adjustment in case you go the wrong way and make it worse.

Does anyone that installed the 2008-2010 zx10r shock experience this wobble? That shock raises the rear quite a bit, I know mine is very stable with the rear end up higher and I think it handles better with a higher rear/lower front.
 

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Da Braddah mentioned weight distribution.
Less preload on the front and more preload on the rear will shift the weight forward a bit, then again, so will dropping the forks.

You used to get tankslappers when on the gas, weight goes back and the front tyre is just skimming the Tarmac, so the bars start to slap back and forth. Mild version is a bit of a wobble.
Put some weight over the front end.
 

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Rear tire straight? Never trust the swing arm marks. Mine are way off.
 

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Discussion Starter #17
I bought a proaligner to align the tires. It was off one full turn in on the right. Took it for a spin and seemed the same. I don't know if I fully trust the proaligner but aligning motorcycle tires is a real head scratcher. I wish I would've paid attention before I had dealership change the tires because like I said it was off one full turn and the chain rides rides to the left of the sprocket, inside of the right side of the chain. Does everyones sprocket run in the middle of the chain? I'll double check the alignment again and I'll change the preload on the front and back. Thanks for the help everyone Cecil, Keef, Motomania, and DNFDOUG.
 

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I use to get a bit of wobble on occasion accelerating on uneven roads. GPR stabilizer on now and no issues since.
 

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I bought a proaligner to align the tires. It was off one full turn in on the right. Took it for a spin and seemed the same. I don't know if I fully trust the proaligner but aligning motorcycle tires is a real head scratcher. I wish I would've paid attention before I had dealership change the tires because like I said it was off one full turn and the chain rides rides to the left of the sprocket, inside of the right side of the chain. Does everyones sprocket run in the middle of the chain? I'll double check the alignment again and I'll change the preload on the front and back. Thanks for the help everyone Cecil, Keef, Motomania, and DNFDOUG.
I have a Motion Pro alignment tool that I use after I do the string method.
tire.jpg
 

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Speed wobble typically is from worn front tire, or insuficient front preload. More preload will increase rake, which makes the bike more stable...
 
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