Steering Squirm ~~~~~~~~
JerryR
Posted 8/2/2004 12:10 AM (#4280)
Subject: Steering Squirm ~~~~~~~~



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Posts: 122
100
Location: Colorado Springs, CO
I posted this on one of the Gl-1800 boards and thought it may be of some interest here too.




Along the lines of Head Shake and Wobble I'll give my input about Squirm ~~~~~.

When I put our Sidecar on our early '01 Wing in late '02 I noted a Squirm on most any surface the was Gro~~~oved or other wise cut in a similar pattern from the Concrete sections along I-25 to the Prep Milling for new pavement. The front of the bike would follow every irregularity with the sidecar on and an assortment of Front tires starting with 2 ME880's fronts to a M-50 bias ply rear, and a 'Lop 204 Sportmax rear which is a radial. Note that the Hot Setup for Trikes and Sidecars is to use a Rear Tire on the Front due to the flatter profile, deeper tread & harder rubber.

Anyway the bike had the normal Headshake that some report with only 2 wheels which is much more severe than any of you Easy Riders can imagine. That was helped with the addition of a Steering Damper from a truck application which was installed with the Hack.
Sidecars always have severe problems with Headshake unless you replace the front end in total with a unit based on an automotive wheel and suspension for $$$$$ which relagates the bike to Sidecar Only.

The Squirm however was always there and at such a frequency and amplitude that the Steering Damper didn't help it. For almost 2 years I avoided those Gro~~~~oved sections of road whenever I could and found alternate routes whenever possable.

Fast forward to my addition of a set of All Balls Taperd Roller Bearings to replace the Bicycle type Ball Bearings that Honda put in the bike to make it feel "Sporty".
After replacing those old bearing which were fully lubed with the specified "Pull" the bike with Hack was much better for Headshake Controll, enough so that I removed the Steering Damper. It still has Headshake and always will with the OEM forks/tripple clamp but it is much improved.

Along with the improvement with Headshake came a total absence of SQUIRM !!!!
It's GONE

Note that when installing the Tapered Roller Bearings I set the inital Torque at 30 lbs then rode the bike for several K miles over some of the worst roads you will ever take a Wing and rechecked the Pull. The Shakedown trips included riding from Victor to H-50 on Phantom Canyon, 35 miles of total Washboard with crators, and the full length of the Rampart Range Road, another 40+ miles of Washboard & crators.

It is stable at a little over 5 lbs Pull using a Trigger Gauge which is inline with the Pull on a 1500 with similar Steering Stem Bearings.

Most will never have the pleasure of Piloting a Hack with their tendancy toward Headshake and in the case of the 1800 Squirm. If you do and need a fix or improvement remember that the folks who make Trikes kits that have similar problems at times all supply Custom Steering Stems with Tapered Bearings for a reason.

Who knows some of you Doubting Thomas's may even find that your bike that Squirms with tire wear and develops Headshake can find improvment with Tapered Bearings too.

Jerry
_________________
CO, Jerry & Sharlene with Misty, Peaches and Rusty on the Side (Car that is)
'01 Yeller + '02 Escort
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Hack'n
Posted 8/2/2004 4:19 PM (#4297 - in reply to #4280)
Subject: RE: Steering Squirm ~~~~~~~~



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Jerry R. stated;
"Sidecars always have severe problems with Headshake unless you replace the front end in total with a unit based on an automotive wheel and suspension for $$$$$ which relagates the bike to Sidecar Only."

I find that I am unaware of this universal problem. Having mounted hundreds of sidecars on almost all brands, old and new.

I'm happy they found a solution for that particular combo but an uncontrollable head shake can be caused by any number of reasons. Some of which are; Out of round or out of balance tires or wheels, bent wheels, weak or worn front suspension components, bent swing-arm, worn swing-arm bushings, The wheel bearings (which he covered), a misaligned sidecar, weak rear shocks, loose or worn head bearings, loose sidecar mounting and other stuff I can't think of right now.
A light nose wiggling tendency at some lower speed when starting off or slowing down is the nature of the beasts, but for severe shake, usually there are other problems not necessarily associated with the front end rake and trail. Auto radials or other flat tread tires will have a tendency to follow rain grooves and pavement seams.
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JerryR
Posted 8/2/2004 6:26 PM (#4303 - in reply to #4280)
Subject: RE: Steering Squirm ~~~~~~~~



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Posts: 122
100
Location: Colorado Springs, CO
To get my comment into perspective you would have had to be on the 1800 boards where they are gauging the Head Shake problem by removing both hands from the bars while decelerating on the 2 wheel bikes. One test that has been recomended over there is to take both hands off the bars while in cruse at 40 MPH then use one fist to rap one grip hard and induce a Wobble. Hopefully all who try that test will be able to recover quick enough to prevent a tank slapper. Most if not all 1800's will go into a severe head shake with any bump and sometime without with both hands off the bars while dropping through the Wobble Zone of 40 to 30 MPH or so.

From my past several decades of Hack Rigs they all have a tendency to go into Very Severe Head Shake under those conditions with both hands off the bars. Not a good thing to do. I have ridden quite a few rigs put together by long term experts and I can't think of one that I would ride without hands as some of the 1800 folks insist the 2 wheelers should be capable of.
Other than those conditions that the 2 wheel 1800 riders are gauging the 1800's Wobble Problems I don't think that there is a a problem with most sidecar setups.
I did find that with the Tapered Bearings the tendency to Shake it's head with the OEM Tripple Tree on is minimized to the point that I removed my Steering Damper and am comfortable that way as long as at least one hand is on the bars at all times. Of cource the same should be done even with a Streeing Damper on the bike.

Jerry
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Hack'n
Posted 8/3/2004 3:48 PM (#4309 - in reply to #4303)
Subject: RE: Steering Squirm ~~~~~~~~



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Jerry,
That is another realm; hands off and slap the bars. Sounds like Japanese roulette. I always recommend hands on operation with any hacks.
I'm wondering how the Runes will react with their unusual front end geometry when hacked. Heard any noise regarding that?

Lonnie
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