Author Topic: Shimmy in front end after front tire replacement?  (Read 13091 times)

Offline brahall

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Shimmy in front end after front tire replacement?
« on: September 28, 2007, 02:25:46 PM »
I replacement my front tire and now at 40-45mph I have a shimmy when I let go of the handle bars. I took the wheel back to the place that mounted it and they re-balanced it but it's still there. I have checked and the dampening screws for the front forks and they are adjusted equal. What else could it be.
Is there a specific order and torque for tightening the pinch bolts and axle bolts?
Any suggestions would help.
Thanks,
Brian
Bandit GSF1250S (Black)

Offline txbanditrydr

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Re: Shimmy in front end after front tire replacement?
« Reply #1 on: September 28, 2007, 03:09:53 PM »
Quote from: "brahall"
Is there a specific order and torque for tightening the pinch bolts and axle bolts?
Any suggestions would help.


Yes, there is a specific order....   you'll want to torque up the axle BEFORE the pinch bolts are tightened.  Also, the 2G Bandits have you bounce the forks up and down several times prior to tightening the axle (per the service manual).

The axle should be tightened to 72.5 ft. lbs. - I have the pinch bolt number at the house and will post it later if someone doesn't beat me to it.  (guessing around 16.5 ft lbs. based on my less than stellar memory).

Most likely though, it'll be associated with the steering head bearing tightness.  There have been reports of the new 1250's being delivered with loose heads.  If that's not the case it could be the tire itself - some front tires don't play well some rear tires.

Good luck or keep your hands on the bars.   :bandit:
'01 B600S ... sold
'05 B1200S ... Top 20 mods... #20 through #2 - All The Usual Ones, Yada, Yada  & #1... 150,000+ Miles and Counting!!!!

Offline pmackie

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Shimmy in front end after front tire replacement?
« Reply #2 on: September 28, 2007, 05:47:29 PM »
Hi Brian, as tx alluded to, some tires seem to cause a shimmy or slight wobble at certain speeds.

Usually this is a tire with a centre tread groove running radially around the tire (like the Bridgestone BT-20). Others tires that DON'T have a centre groove are less susceptable (like the Michelin Pilot Roads).

I had a shake at 38-42 mph on my B6 that went away when I made two changes:
1. Moved to a 120/70 series from a 120/60 series
2. Moved to a tire with NO centre groove. I have used Bridgestone BT-21 and Michelin Pilot Roads, and both were OK.

On my B6, both the OEM BT-56 and the BT-20 that replaced it had a shimmy.
Paul
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Offline aussiebandit

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Shimmy in front end after front tire replacement?
« Reply #3 on: September 30, 2007, 03:59:35 AM »
Quote from: "pmackie"
Hi Brian, as tx alluded to, some tires seem to cause a shimmy or slight wobble at certain speeds.

Usually this is a tire with a centre tread groove running radially around the tire (like the Bridgestone BT-20). Others tires that DON'T have a centre groove are less susceptable (like the Michelin Pilot Roads).

I had a shake at 38-42 mph on my B6 that went away when I made two changes:
1. Moved to a 120/70 series from a 120/60 series
2. Moved to a tire with NO centre groove. I have used Bridgestone BT-21 and Michelin Pilot Roads, and both were OK.

On my B6, both the OEM BT-56 and the BT-20 that replaced it had a shimmy.


I had the same 'shimmy' problem on my 02B12.  I lost count of how many times I took it back to the dealer getting them to check 'everything', then one of the parts guys suggested a new front tyre, one without a centre groove or grooves.  On his recommendation I put a Metzler M1 on the front and hey presto no front shimmy - I would suggest that if the front end didn't shimmy before the new tyre and that's the only change you've made - then I'd either put up with it, or cut your losses and get another new front tyre - one without centre grooves.
AUSSIEBANDIT (MICK)
02B12

"Nothing is foolproof to a sufficiently talented fool"

Offline brahall

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Thanks for the reply's
« Reply #4 on: September 30, 2007, 12:55:15 PM »
The tire I am using is a Dunlop Sportmax Qualifire and it has no center groove. The only other thing it could possibly be is the order/torque of tightening the bolts or a bad tire.
When tightening the bolts the only way I could possibly torque down the axle bolt before tightening the pinch bolts is to have a rather LARGE allen wrench to hold the axle from turning while tightening the primary axle bolt.

Bandit GSF1250S (Black)

Offline gunz

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Shimmy in front end after front tire replacement?
« Reply #5 on: October 06, 2007, 12:07:02 PM »
Quote from: "aussiebandit"
Quote from: "pmackie"
Hi Brian, as tx alluded to, some tires seem to cause a shimmy or slight wobble at certain speeds.

Usually this is a tire with a centre tread groove running radially around the tire (like the Bridgestone BT-20). Others tires that DON'T have a centre groove are less susceptable (like the Michelin Pilot Roads).

I had a shake at 38-42 mph on my B6 that went away when I made two changes:
1. Moved to a 120/70 series from a 120/60 series
2. Moved to a tire with NO centre groove. I have used Bridgestone BT-21 and Michelin Pilot Roads, and both were OK.

On my B6, both the OEM BT-56 and the BT-20 that replaced it had a shimmy.


I had the same 'shimmy' problem on my 02B12.  I lost count of how many times I took it back to the dealer getting them to check 'everything', then one of the parts guys suggested a new front tyre, one without a centre groove or grooves.  On his recommendation I put a Metzler M1 on the front and hey presto no front shimmy - I would suggest that if the front end didn't shimmy before the new tyre and that's the only change you've made - then I'd either put up with it, or cut your losses and get another new front tyre - one without centre grooves.


i had a like problem with my COncours. i got away from the dunlops and went to michelin adn the wobble went away also. i had dunlop sport radials, then went to dunlop sport max and finally went to michelin pilot adn that solved it. i lived with it for almost 9 month of riding and 2 sets of tires. I wont be replacing my stock dunlops with  more dunlops
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