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High Speed Front Wobble/instability ?


raoufhakam

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anyone experienced this before?

the front feels a bit sloppy at high speed -above 200km/h = 120mph- was trying to see how was vfr can go and just beyond the 180 or 200 km/h the front feels like riding on soapy water at these speeds, and just up to 240 km/h (150 mph) i felt like the bike wont go further or the front end is almost gonna come apart.

any idea or input? is my forks too soft? maybe with age its just not capable or was not designed for these speeds?

compared the CBR600RR i had before my VFR, the CBR just feels planted on the road at highspeed and goes in a straight line like a dart at similar speeds. mind you it was 6 years newer, lighter and better suspension

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First, stop riding so fast as the symptoms you point out do not sound good. Second, it could be steering head bearings, possibly suspension needs maintenance if the fork oil is old. Although you are trying to compare a 5th gen to a CBR600RR I will say that I have a 2001 and I get nothing like this and I have had the suspension at it's softest setting for a while due to the excellent evenly paved roads (sarcasm) here in Britain. I think you should have your bike checked out.

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What you described could be caused by several things: low tire pressure, worn tires, bad wheel bearings, and (my personal pick) worn steering head bearings. My '99 is rock solid at any speed I've attempted, approximately 135, according to bicycle computer I have mounted max speed readout.

I'd be looking very hard for the issues before I rode very much more. It may feel okay at slower speeds but something ain't right.

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I've had mine up to an indicated 165 mph with zero issues. Something is wrong & needs to be corrected....sooner rather than later.

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In addition to checking your steering head bearings, also check your front tire for any excessive cupping or any other unusual wear patterns too, as they can cause all sorts of weird front end behavior on the bike.

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What you described could be caused by several things: low tire pressure, worn tires, bad wheel bearings, and (my personal pick) worn steering head bearings. My '99 is rock solid at any speed I've attempted, approximately 135, according to bicycle computer I have mounted max speed readout.

I'd be looking very hard for the issues before I rode very much more. It may feel okay at slower speeds but something ain't right.

Low tyre pressures, badly worn tyres or loose steering head bearings would do this. After you've checked the tyre pressures, get the front end off the ground (not during a wheelie) and grab the bottom of the fork legs and give them a good shake front-back and then side to side. While you are down there check the wheel bearings as well for freeplay. Also turn the bars fully from side to side, the action should be smooth, not notchy.

There might be a little play in the slider bushes but you should not feel a clonk through the steering head. If you do, the bearing either needs adjustment or replacement. If you tighten the bearing a little to get rid of the freeplay and the bearing gets notchy then the races are dented by the ball bearings and must be replaced. Don't over-tighten the bearings either; this makes the steering kind of sticky, and you end up over-compensating and it becomes impossible to take a smooth clean arc round a bend. Ask me how I know....

As previous posts have stated, don't try the "let's see what she'll do!!!" trick again until you've got this sorted. The steering oscillations you describe can get worse and cause a full lock-to-lock tankslapper, and that ain't no fun, kids. I survived the era of the 16" front wheel!

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I'd check the cheap and easy things first: air pressures, front tire/fork for play or looseness-just hold the tire and try to wiggle it, then try to move the forks like mentioned above (the steering head bearings). The front tire for odd wear patterns, back tire for a very squared off shape (also old hard, cracked tires), Check rear wheel/tire/swing arm for play-try to wiggle them like the front,

I've not found the cbr600's to feel any more planted than my '94, quicker no doubt but not more steady and solid feeling.

I wouldn't be going 50 on a bike that didn't feel good at 70.

Something is wrong and find it now, because later you won't have a chance.

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I had a similar issue on my '03 vfr. At anything above 90mph it would shake and vibrate badly. It also wobbled real bad if I took my hands off the bars. I wasn't sure if it was wheel bearings, or steering head bearings, or the tire. It turned out to be the front tire was badly scalloped. After putting on a new Michelin PP (thanks gr8vfr)the problem was solved. Now it feels great at triple digit speeds.

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