TNRC51 Posted July 16, 2014 Share Posted July 16, 2014 Over the weekend I discovered a quirk of my VFR. On an empty stretch of road I was coasting down and decided to stretch my back for a second. On my other bike I can sit up with my hands off the bars with no issues or drama at all. On the VFR it immediately started shaking its head. As soon as i touched the grip with either hand it stopped. Mind you i did not let it get carried away. Im thinking it could be a tire issue. Anyone else noticed this with their 6th gen?. Link to comment Share on other sites More sharing options...
Member Contributer Switchblade Posted July 16, 2014 Member Contributer Share Posted July 16, 2014 Mine doesn't !!! ride with no hands a bunch ... Link to comment Share on other sites More sharing options...
Member Contributer MaxSwell Posted July 16, 2014 Member Contributer Share Posted July 16, 2014 I've experienced the same thing on a couple of bikes. Both times it was steeringhead bearings. The recommendation is to replace them with tapered roller bearings. All Balls is the usual product. Once on a bike with only 28K miles on it, the other at 70k. To check, have the bike on the centerstand and weight the back of the bike so the front wheel is off the ground. (Someone leaning on the back of the seat works; or get your really big dog to sit back there.) With your hands on the bars, turn the wheel slowly back and forth; you are looking for a "notch" or detent near the straight-ahead position. Another possibility is an unbalanced or otherwise improperly behaving tire? Good luck. Link to comment Share on other sites More sharing options...
Member Contributer Cogswell Posted July 16, 2014 Member Contributer Share Posted July 16, 2014 I have as well, though from a different source than MaxSwell. At about 1,000 miles my Pilot Road 3's developed a scalloping of the tread and the head shaking began. It usually occurred at about 35 to 40 mph while slowing to a stop. As the tires wore and the scalloping got worse, so did the shaking. After I switched to my Road 2's the shake disappeared and after 7,500 miles with them never returned. Probably after I accumulate enough miles the S.H. bearings will give trouble - I'm just not there yet. Link to comment Share on other sites More sharing options...
Member Contributer Ultimatevfr Posted July 16, 2014 Member Contributer Share Posted July 16, 2014 I have 30,000 on my 07', I let go a lot as well to rest my hands. No problems at all, have new Q3 's on. Link to comment Share on other sites More sharing options...
Member Contributer BusyLittleShop Posted July 16, 2014 Member Contributer Share Posted July 16, 2014 Technically speaking its called a deceleration shimmy and it's normal...some bikes may shimmy decelerating through the 45 mph range... keepingyour hands on the bars should arrest most of the front end shimmy...some bikes shimmy more than others and it's no big deal with yourhands on the bars in the critical speed range... your bike should beimmune at speeds above 45 mph...Deceleration shimmy is chiefly the product of non OEM or a worntires... it ain't the product of tire cupping... but low pressure orloose steering head bearings defeat the tire's corrective efforts...because every bike has this instability... it is held in check bydamping forces created mainly by the tire's self-correctingtendencies... Link to comment Share on other sites More sharing options...
Member Contributer Ultimatevfr Posted July 16, 2014 Member Contributer Share Posted July 16, 2014 Technically speaking its called a deceleration shimmy and it's normal... some bikes may shimmy decelerating through the 45 mph range... keeping your hands on the bars should arrest most of the front end shimmy... some bikes shimmy more than others and it's no big deal with your hands on the bars in the critical speed range... your bike should be immune at speeds above 45 mph... Deceleration shimmy is chiefly the product of non OEM or a worn tires... it ain't the product of tire cupping... but low pressure or loose steering head bearings defeat the tire's corrective efforts... because every bike has this instability... it is held in check by damping forces created mainly by the tire's self-correcting tendencies... Uh ,yeah what he said..............;) Link to comment Share on other sites More sharing options...
marriedman Posted July 16, 2014 Share Posted July 16, 2014 On my 5th gen, I had a wobble on decel that was fixed with tapered bearings. I am now having wobble on my 6th gen. This time though, I believe it is from the tires being scalloped. It is very noticeable just by looking at them. There is plenty of tread left, but I got roughly 7 or 8 thousand miles out of these PR2's. Link to comment Share on other sites More sharing options...
Member Contributer BusyLittleShop Posted July 17, 2014 Member Contributer Share Posted July 17, 2014 On my 5th gen, I had a wobble on decel that was fixed with tapered bearings. I am now having wobble on my 6th gen. This time though, I believe it is from the tires being scalloped. It is very noticeable just by looking at them. There is plenty of tread left, but I got roughly 7 or 8 thousand miles out of these PR2's. Scalloping is a natural wear pattern on motorcycle tires and it will always follow the tread pattern. It is not a contributor to the normal deceleration shimmy. It merely shows that your tire is indeed gripping the road when you make turns (thank you for that Mr. Tire!). This scalloping develops within the side wear bands of a leaned motorcycle because of the extreme forces that come in to play when the bike is leaned in a turn. The leading edge of the tread does not flex much as it grips the road and the rubber is scuffed off the tire in that area causing a depression. As the tire rotates, the pressure moves to the trailing edge of the tread pattern where the tread flexes more causing less scuffing so less material is ground off the tire. The more complex the tread pattern, the more complex the cupping pattern will be. The softer the compound of the tire, the sooner this cupping will develop. Low tire pressure will exacerbate this wear pattern and you will lose many serviceable miles by running low. Improper balance has nothing to do with cupping on a motorcycle tire. Improper balance will merely cause your bike to vibrate within certain specific speed ranges. Link to comment Share on other sites More sharing options...
spud786 Posted July 17, 2014 Share Posted July 17, 2014 The bearings are not the source, its the tire. If you have an issue with a particular tire, it will be worse with loose bearings verses snug bearings. So bearings can mask the issue to some degree or make it show up worse. I run ppower fronts straight as an arrow, no hands at any speed, post 100,000 mile on stock bearings. Link to comment Share on other sites More sharing options...
zRoYz Posted July 17, 2014 Share Posted July 17, 2014 I have owned many bikes & deceleration shimmy can happen but the only times my bikes have had front end wobbles with no hands on bars is due to the tyre, certain tyres even when balanced just tend to do it & it's not a characteristic of one particular tyre. You can use the same tyre brand for years with zero problems & then one tyre will just cause the problem, yes there can be other reasons like steering head bearings, wheel bearings, tyre not balanced, warped brake rotor, binding brake calliper, etc but every time I have experienced the problem a tyre change fixed the problem. You don't have to change tyres just keep your hands on the bars, the only time you may have a larger problem is if you experience wobble with your hands on the bars. Every ride I have both hands off the bars for short periods of time mainly just to stretch out & again have never experienced deceleration shimmy myself. Not every tyre is perfect even in motogp low volume produced tyres with massive quality control so the mass produced tyres you have to expect a few to act strangely. Link to comment Share on other sites More sharing options...
HighwayStar2009 Posted July 18, 2014 Share Posted July 18, 2014 Tires are the culprit. On my first tire change at about 4500mi., wobble on decel from 54mph to 40mph with no hands. One hand stops it but it's annoying. Will see if it stops with the 3rd front tire. Link to comment Share on other sites More sharing options...
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