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[johnmowcop]

Point for discussion.

I have a friend who has a Heritage Softail Classic. I have the CVO RoadGlide Ultra.

We both ask the same question, why do these bikes go into a tank slapper if you take both hands of the bars.

Also what is the reason for the head stock design, the stem is in front of the fork legs in the yolks (or as the current description is "triple clamps". (Bit like swingarm instead of swinging arm)). As far as I know the Harley is the only bike to do this, put the fork legs behind the stem I mean not the tank slapper.

Your comments would be appreciated.

JohnT

[GregKhougaz]

Hey John,

I can't tell you about the Heritage but many Roads Glides seem to need their steering head bearings adjusted, usually tightened.  Mine did back in '09.  We called it deceleration wobble.  If you check the SERG board you'll find a couple of threads on it.  Good luck!

[North Georgia Hawg]

Point for discussion.

I have a friend who has a Heritage Softail Classic. I have the CVO RoadGlide Ultra.

We both ask the same question, why do these bikes go into a tank slapper if you take both hands of the bars.

Also what is the reason for the head stock design, the stem is in front of the fork legs in the yolks (or as the current description is "triple clamps". (Bit like swingarm instead of swinging arm)). As far as I know the Harley is the only bike to do this, put the fork legs behind the stem I mean not the tank slapper.

Your comments would be appreciated.

JohnT

Harley went to the inverted design with the forks sitting behind the steering head years and years ago on the Touring bikes... I think when the FLHT first came out with the bat wing fairing. The idea was to make it easier to turn the very heavy front end and improve handling... and it worked.

As far as RGs having the instability, I don't know. Perhaps it's because the frame mounted fairing catches the wind, and there is no stabilizing factor like a bat wing catching the wind to help prevent it. I have read a number of posts on this forum and others complaining about instability on RGs, particularly at low speeds. I've never read a post complaining of that on the bat wing bikes, nor on RKs. Kinda weird.

The Softail is a completely different bike, so I have no idea why it would have the problem, too.

Ken

[sadunbar]

Point for discussion.

I have a friend who has a Heritage Softail Classic. I have the CVO RoadGlide Ultra.

We both ask the same question, why do these bikes go into a tank slapper if you take both hands of the bars.

Also what is the reason for the head stock design, the stem is in front of the fork legs in the yolks (or as the current description is "triple clamps". (Bit like swingarm instead of swinging arm)). As far as I know the Harley is the only bike to do this, put the fork legs behind the stem I mean not the tank slapper.

Your comments would be appreciated.

JohnT

I had an '97 Heritage Softail and had an '01 SE Road Glide, and neither were unstable, whether holding the handlebars or not.  I'd question if you have mechanical issues with your bikes.  Perhaps tires, alignments, loose bearings in the swing arm or neck?  Personally I'd due a thorough inspection of your rides and look for something abnormal...

[Royalroadie]

 Take a close look at your bearing and nut in the stem.  They are probably loose.  I believe that HD went to the forks behind the steering stem for the police bikes so they could make a sharper u turn for traffic officers.

[screaminCVO]

My '13 RG on deceleration as mentioned earlier did that. They just tightened up the head bearing and all good.

[Cvostu]

I rode an 11 serg and I'll never forget what that wobble felt like. It was while decellerating.  About 35 mph.  I was so happy to bring it back. Stuart

[FLSTFI Dave]

That happened on my 09 Road Glide, coasting down with hands off bars at about 42 going down it would go into the tank slapper.  Like mine others on the forum had the Dealer adjust the neck bearing to the special spec for the RG that had just come out.  Problem fix.

My 12 CVO road glide never had it until after the 40K service.  Noticed it right away, pulled the bike back in and asked them to adjust the neck bearing to the Road Glide Specification not the Touring bike spec, again problem solved.

Have just over 4 K on the 15 CVO RG Ultra, have not noticed it yet at any speed.

[grc]

Harley uses a very imprecise method for setting and checking the steering head bearing preload on previous model year Touring bikes, called the swing test.  Back in 2009 Harley made the mistake of using the same spec for the Road Glide that is used for the batwing bikes, and that lead to a lot of very loose head bearings in Road Glides.  Think about it for a moment; the batwing rotates with the forks and adds considerable mass when performing the swing test.  The RG fairing is not connected to the forks at all, and thus the RG front end has much lower mass during the swing test.  Simple inertia explains why the RG with correctly set bearing preload will have fewer swings than an EG with the same real bearing preload.  Someone at Harley finally realized that and released new specs that showed a significant reduction in swings for an RG versus an EG after a huge number of reports of front end low speed wobbles on RG's in 2009.

Harley changed the test method for the 2014 model year and no longer uses the swing test, btw.  But of course that doesn't mean they learned how to set the front ends any better in production than they did before.  If you still have instability on a 2014 and later, have the dealer recheck the steering head bearing preload.  Remind them if they start to do an old fashioned swing test that they need to use the new method.

Jerry

[Jswerve]

Jerry what exactly is the new method?

[North Georgia Hawg]

Jerry what exactly is the new method?

I was wondering that, too. My service manual says to use the swing test, and I'm curious as to if the new '14 test - whatever it is - could be used on our older bikes.

Ken

[grc]

The "new method" is similar to the old method that's been used on the Dyna's and Softails all along, called the fall away method.  They chose to name the new method for the Touring models the "swing back method".  See the following attachments.

Jerry

[grc]

Illustration #2

Click on them to enlarge enough to read clearly.

Jerry

[GregKhougaz]

     Very scientific!    

[grc]

    Very scientific!    

    Yeah, very cutting edge, for the 1800's.  These people are bound and determined to only be dragged into the current century when they are given no other choice, kind of like the late model EFI that was made necessary by government regulation.  Without the EPA you'd still have carburetors.

I found it interesting that they mention the Trike doesn't use either method, but rather a torque measurement.   DUH!   

Jerry