Author Topic: Speed wobble with PR2's? (Read 7176 times)

Irish-14 · « **on:** June 05, 2011, 07:49:11 PM »

Ok, some of you might remember me as the idiot that hit the huge rock and blew out my rims and tires a few short weeks ago. The shop said that everything else was ok with the bike and put two new rims and new PR2's on it. This weekend I rode to Palm Desert for a bachelor party and experienced high speed wobbles on any speed over 110mph, something I'd never felt on this bike in the past. I've had the bike at 150mph without an issue on several occasions with the original Bridgestone's that come on a 2011. Not sure what the problem could be, maybe I cracked/weakend the frame, fork issue, but I thought you guys might have an idea or two. I'm not jumping to conclusions about the PR2's, just a thought. Thanks for any input, and as always, Go Irish!

Bob · « **Reply #1 on:** June 06, 2011, 03:13:12 AM »

Did they ballance the tires? I know dumb question, but you never know!

VirginiaJim · « **Reply #2 on:** June 06, 2011, 04:22:48 AM »

Hitting a rock that damaged the wheel could have also damaged other components such as wheel bearings, axle shaft, forks, and steering head bearings/assembly. Any or all of those components could cause wobble.

S.Ga.Rider · « **Reply #3 on:** June 06, 2011, 04:39:16 AM »

I have a pr2 front and a shinko 009 and I get a wobble in the bars over 110 also. Mine didnt do it with the stock tires either. I have rebalanced both tires and adjusted the suspension with no luck. Im going to try the 023s next time to see if it is the tires.

stewart · « **Reply #4 on:** June 06, 2011, 05:56:50 AM »

I was riding the other day in a really strong wind and experienced a wobble at around 90mph, was going to investigate but then I hit 130mph the following day and solid as a rock.

I put it down to the wind.

Jeremy Mitchell · « **Reply #5 on:** June 06, 2011, 06:22:37 AM »

I have noticed that the wind has a lot to do with how the front end feels if I have my Vstream on. When I have my cut down stock shield on the wind doesn't make any difference.

jayke · « **Reply #6 on:** June 06, 2011, 06:40:24 AM »

Never had any wobble trouble with my PR2's over several sets.

But I did spin a tire on the rim once right after it was installed before the lube was dry and had to have it re-balanced. Have them re-balance the tires as a first step.

Might have them check the tightness of the steering head bearings also. Loose steering head bearings will cause a wobble too.

jjsC6 · « **Reply #7 on:** June 06, 2011, 08:34:06 AM »

Two sets of PR2s and zero wobble. The bike sees over 100 every time out

Irish-14 · « **Reply #8 on:** June 06, 2011, 08:53:51 AM »

Thanks for the suggestions, I'll call the shop today and talk to their main tech. I'll let you know what they say/plan to do. Go Irish!

vortex2 · « **Reply #9 on:** June 06, 2011, 08:58:11 AM »

It's not the tire design. It may be a balance problem.

Tom J. · « **Reply #10 on:** June 06, 2011, 09:05:22 AM »

Reminder to check the tire pressure.

lt1 · « **Reply #11 on:** June 06, 2011, 11:29:18 AM »

Yes, but mine came in at about a buck and a quarter. Heavily loaded, with GPS on a Ram bar mount on one side and a radar detector on a Ram bar mount on the other side. Removing the trunk didn't make any significant difference. I have come to the conclusion that it was the combination of the excess weight in the bags & on the bars that caused the problem.

I'm still not sure if the PR2's were a contributing factor or not. No weave w/ the oem 'stones.

The experiences were intense enough to affect mine desire for further experimentation. The first one lasted over 30 seconds - 1 mile with the bike rocking back and forth about a foot. The 2nd was about half that. Makes for an interesting day.

tthompsr · « **Reply #12 on:** June 06, 2011, 11:42:00 AM »

I had a high speed wooble that took me a while to figure out, It went away when I changed my steering head bearings over to a tapered bearing.

Dave Bogue · « **Reply #13 on:** June 06, 2011, 12:38:44 PM »

Quote from: lt1 on June 06, 2011, 11:29:18 AM

The experiences were intense enough to affect mine desire for further experimentation. The first one lasted over 30 seconds - 1 mile with the bike rocking back and forth about a foot. The 2nd was about half that. Makes for an interesting day.

You are a brave and foolhardy man to ride 30 seconds at high speed with a handling problem. I can tell you from experience that a slight weave at 120 mph can turn in to an uncontrollable wobble that will throw you and the bike down the road.

I have seen 165 mph indicated on my 2009 ( no bags, 4" cut down windscreen, no flies, AreaP full, PC3) with Pilot Road 2s and the bike was rock solid.

I do not think the problem is the tires.

Best wishes,
Dave
Bradenton Florida
Sunday rides on the best winding and scenic roads in west central Florida

lt1 · « **Reply #14 on:** June 06, 2011, 01:42:27 PM »

Whether I am/was brave or foolhardy is irrelevant to the discussion. I was accelerating hard when the weave hit (in both instances), and easing out of the thottle intensified it. It was merely a question of prayer, relaxing on the bars, staying off the brakes, and verrrrrry gradually easing out of the throttle. If I could have gotten out of it any quicker, I would have. Believe me, I would have like the merry-go-round to have stopped so I could get off without dieing. It took very minute reductions of throttle to not exacerbate the situation. FWIW, the 2nd time was about a year after the first, not just a few minutes later. LOL

I do believe the tires played a role in the problem, but I do not believe they were "the cause". Tire stiffness is one of many factors in a high-speed weave, but it is not the only one.

Quote from: Dave Bogue on June 06, 2011, 12:38:44 PM

You are a brave and foolhardy man to ride 30 seconds at high speed with a handling problem. I can tell you from experience that a slight weave at 120 mph can turn in to an uncontrollable wobble that will throw you and the bike down the road.

I have seen 165 mph indicated on my 2009 ( no bags, 4" cut down windscreen, no flies, AreaP full, PC3) with Pilot Road 2s and the bike was rock solid.

I do not think the problem is the tires.

Best wishes,
Dave
Bradenton Florida
Sunday rides on the best winding and scenic roads in west central Florida

pb · « **Reply #15 on:** June 06, 2011, 03:18:08 PM »

Had PR2's installed at 8500 miles.
Now at 12,500+. I don not play had those speeds often.
So it was while before I noticed it.
Odd that it is 110 also. Was there after installed.
I noticed it after I rode a few K miles.
No speed demon but I do play now and then.
Wobble was not there till higher speeds (130's) on the brimstones.

Purchased while out of town one day.
Figured it was just not a good balance job.
I also notice some buzz at he 80+ range. That was not there before.

Next time I go that way, I will talk to the dealer and see what they say.
But imagine I will end up paying for balance at some point, having waited so long.
Don't you hate when work keeps you from playing. :-) Have not had the chance to go that way for months.

I have question though?
I had a corolla that had warped brake rotors.
The tires balanced fine. But at 75+ you would swear other wise.
Made me and the tire guy nuts, till I figured it out.
Did not show up until I replaced the tires.

Do the rotors on the bike have enough mass to cause this?
I checked the brake pads and rotors last night.
Both look warn of course, but nothing unusual for almost 13k pads/rotors, jumped out.
No obvious signs of warping or gouging.
Both pads and rotors appear to be warn fairly smoothly.
As best I can tell with them on the bike anyway.
They still feel smooth and even when using them also.

Paul

Irish-14 · « **Reply #16 on:** June 06, 2011, 05:44:56 PM »

Actually I had more weight in the bags than I've ever had in them before, I was packed for a three day bachelor party, never thought of that. You're also right about the abrupt decel, made it worse, almost crapped my pants. Still having it go to the shop to look at the darned thing, never want to feel that again and I fully intend to travel at hyperspeed in the future...that's why I bought a 1400cc! Go Irish!

Rawman · « **Reply #17 on:** June 07, 2011, 04:00:10 PM »

I have been 0 to 149 WOT (GPS). I have been slowly up to 149 (GPS). Never had any wobble, vibration, or any other issues, it was rock solid. I had the Givi V46, Bags on, VStream screen and it topped out at 149, me laying on the tank with feet on passenger pegs, little to no wind. Long flat straightaway (no traffic anywhere in sight) on the superslab. I need to try it with the OEM screen, no bags and no trunk.

Bradley14 · « **Reply #18 on:** June 08, 2011, 05:07:31 AM »

I recently had PR IIs installed and for the first time ever noticed a low speed wobble (40-50) with no hands on the bars. I figured it was the road or fact I had all 3 bags on and loaded. I'll try different speeds/conditions to see if I can duplicate.

JS_racer · « **Reply #19 on:** August 11, 2011, 04:07:55 PM »

for whats its worth, my last pr2's shook like heck. say 40 had a bar wobble, 80-90 vibration from the rear( fixed after replacing) 100-110 from the front. not sure if balancing again would have helped, it was bad enough to not push it. i think the set before had a vibration to them also.

023 front and rear now and its like glass. not sure what to make of that.

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Author Topic: Speed wobble with PR2's? (Read 7176 times)

Bob