Need Help Experiencing Handlebar Wobble.

[InfernoST]

Hi Gang
I've been experiencing handlebar wobble for quite a while now, I originally chalked it up to the OEM supplied front tire had become scalloped. I recently replaced the front and rear tires with a different set of new dunlops at about 9000 miles and am still experiencing this front end wobble everytime I take my hands off the bars, the front wheel has new tire new bearings, seals, is balanced and not bent (checked with a dial indicator) and runs true. I check the service manual and the information supplied doesn't specifically state how tight the neck bearings spanner nuts should be, I know it has to easy but when the bike is on the center stand and I put my weight on the back of the bike to raise the front wheel off of the ground with wheel facing straight ahead the bars flop to the right side rather quickly which I find very odd. I was concidering of adjusting the spanner nuts just enough to keep the bars from flopping to the right like that. My Bike info is as follows, 2020 NC750X fully manual transmission. Does anyone have any suggestions? FYI I have tried letting go of the bars with the topcase and side boxes removed, either way it's a pretty violent wobble.

 

[CamaroEric]

Quite a few people here have it including myself. Haven't found a solution yet. Sometimes a new tire helps but head bearings are probably too loose or on the loose side of spec. I just keep my hands on the bars though I know it's not a great solution.

The brake line and throttle pull a lot harder than the clutch side so it will go right. You'll have to take the handlebars off so the only variable is the head itself. The old school check for correct nut torque is that the wheel will fall to either side about halfway to the lock. So should stay in place if let go toward the center of steering.

 

[MZ5]

The NCX model has been doing that since at least model year 2012 (which is when it was introduced into the USA market). I have a 2012 that I bought new that year, and it does it. Exactly what tire I have on it has an effect on whether or how much the head shakes. So does my suspension setup, and the load and load balance on the bike. The more weight I have on the bike, especially far to the rear, the more it'll shake its head through a certain speed range on deceleration.

Search for (several) other threads here on the forum (I don't have them bookmarked so I can't just give them to you.). I don't care much about the problem; know it well, know it won't make me crash, and know how to mitigate it fairly well. Nevertheless, make sure your rear spring preload has the bike sitting at the correct static and race sag amounts. You can try raising the forks up in the triple clamps about an inch, too (or, if you like, call it lowering the triple clamps down the forks).

 

[InfernoST]

Thanks for the input guys, this Saturday I'm going to remove the top of the triple tree and make the nut tight enough so the bars dont flop to the right by themselves and see how the steering feels afterwards. A brand new bike shouldn't be doing this especially with all of the luggage removed.
I did try a search but I didnt see much related to the issue. I'll let you know how it works out.

 

[InfernoST]

This is my bikes current configuration. I'm posting this to show how the bike is with all of the luggage, maybe there is something you see that may be a possible issue.

 

[670cc]

Interesting. Well, in case “they all do it” comes up as the root cause, I’ll say I have owned 2 2012 NC700Xs with maybe seven different tire types, stock and aftermarket suspensions, over 70,000 miles of use, and all manner of loaded and unloaded weighting, and wobble/ head shake has never existed in my NC world.

Wish I could offer a solution. I don’t recall reading of any particular fix in this forum.

 

[InfernoST]

Interesting. Well, in case “they all do it” comes up as the root cause, I’ll say I have owned 2 2012 NC700Xs with maybe seven different tire types, stock and aftermarket suspensions, over 70,000 miles of use, and all manner of loaded and unloaded weighting, and wobble/ head shake has never existed in my NC world.

Wish I could offer a solution. I don’t recall reading of any particular fix in this forum.

That is very valuable information because in my eyes it should not exist, I've owned many machine used and new and this is the first bike that is exhibiting this issue and I bought this new as a left over with 2 miles on it in late 2021.

Question, when your front tire is off of the ground do you handlebars flop to any side or does it remain straight ahead? Mine flops as if there is 0 resistance.

 

[dduelin]

Hi Gang
I've been experiencing handlebar wobble for quite a while now, I originally chalked it up to the OEM supplied front tire had become scalloped. I recently replaced the front and rear tires with a different set of new dunlops at about 9000 miles and am still experiencing this front end wobble everytime I take my hands off the bars, the front wheel has new tire new bearings, seals, is balanced and not bent (checked with a dial indicator) and runs true. I check the service manual and the information supplied doesn't specifically state how tight the neck bearings spanner nuts should be, I know it has to easy but when the bike is on the center stand and I put my weight on the back of the bike to raise the front wheel off of the ground with wheel facing straight ahead the bars flop to the right side rather quickly which I find very odd. I was concidering of adjusting the spanner nuts just enough to keep the bars from flopping to the right like that. My Bike info is as follows, 2020 NC750X fully manual transmission. Does anyone have any suggestions? FYI I have tried letting go of the bars with the topcase and side boxes removed, either way it's a pretty violent wobble.

Can't speak to the year of yours but my 2012-2015 copy of the service manual gives torque value of 17 ft/lbs on the adjuster nut to set the correct preload on the steering stem bearings. If you decide to follow this recommendation the manual states to replace the lock washer above the adjuster nut with a new lock washer. Important because after setting the torque you continue by tightening the lock nut above the adjuster nut up to 90 additional degrees and a used lock washer can affect the torque on the lock nut.

You might have done this already but something you can try before messing with the bearings is to remove the front wheel and with the bike on the center stand set the bars straight ahead and see if you can feel a slight notch or catch when you move the bars ever so slightly to one side then releasing the bars. Without the mass of the wheel it's easier to feel this notch or you might see the bars self-center themselves instead of flopping over due to a tiny dents or notches worn in the bearings.

I'm kind of like 670cc. I have had many kinds of motorcycles over the years and some of them never exhibited this slow speed deceleration wobble and others did. The cure could be a new tire(s), changing tire pressure(s) or new bearings or keeping one hand on the bars at all times. I have had three NCs and none of them showed this behavior but then I rarely take my hands off the bars to check for it.

 

[670cc]

That is very valuable information because in my eyes it should not exist, I've owned many machine used and new and this is the first bike that is exhibiting this issue and I bought this new as a left over with 2 miles on it in late 2021.

Question, when your front tire is off of the ground do you handlebars flop to any side or does it remain straight ahead? Mine flops as if there is 0 resistance.

The only time I have the front wheel raised is when changing the tire, but if I remember right it very easily flops to the side. I highly suspect my steering stem is quite loose and could use some maintenance. At 66,000 miles now, I’ve never messed with it.

I must say that taking both hands off the bars while riding is something I never do. However, even with a light grip on the bar, I feel no tendency for wobble.

 

[Ric.down]

Hi Gang
I've been experiencing handlebar wobble for quite a while now, I originally chalked it up to the OEM supplied front tire had become scalloped. I recently replaced the front and rear tires with a different set of new dunlops at about 9000 miles and am still experiencing this front end wobble everytime I take my hands off the bars, the front wheel has new tire new bearings, seals, is balanced and not bent (checked with a dial indicator) and runs true. I check the service manual and the information supplied doesn't specifically state how tight the neck bearings spanner nuts should be, I know it has to easy but when the bike is on the center stand and I put my weight on the back of the bike to raise the front wheel off of the ground with wheel facing straight ahead the bars flop to the right side rather quickly which I find very odd. I was concidering of adjusting the spanner nuts just enough to keep the bars from flopping to the right like that. My Bike info is as follows, 2020 NC750X fully manual transmission. Does anyone have any suggestions? FYI I have tried letting go of the bars with the topcase and side boxes removed, either way it's a pretty violent wobble.

Never had this on a bike - and certainly not on my NC which is as stable as you could wish for. Steering 'should' flop easily to one side or the other - but getting the bike perfectly level to test this is impossible. You mention new tyres, but have these been balanced properly? Definitely do not tighten headset bearing as this will cause binding and premature wear.

 

[the Ferret]

I've had 31 or 32 motorcycles, some have had the shimmied at times, others haven't. If you google handlebar shimmy at 50-40 while decelerating, you'll find posts reporting it across all brands, makes and models.

handlebar shimmy at 50-40 mph while decelerating - Google Search

Back in the 80's when I worked for a Honda shop and the new Goldwing factory dressers came out, they would wobble or shimmy quite often. Honda's solution was to bolt a big lead weight to the steering stem saying people overloading their trunks was changing the weight bias. But since it happens on naked bikes too it is surmised that it could be head bearings, tire imbalance, tire pressure, bad tire, wheel bearings, weight bias transfer and a host of other reasons. No one REALLY knows, and the reason may not be the same for every bike.

I believe in your owner's manual it will tell you to never take both hands off the handlebars, which I believe is lawyer talk for, if you take your hands off the bars, and it shimmies, and you crash, it's not our fault because we specifically told you not to take your hands off the bars.

 

[MZ5]

Concerning handlebars flopping to the right:

Shouldn't we expect that behavior, since the brake disk and caliper are on the right side? I would not expect the bars to stay straight ahead with that weight imbalance at the front axle.

***EDIT:
I'd like to expand by noting that, in my view, we should not expect (nor try to use) the steering head bearings to actively resist turning of the steering head. I believe that, if the bearings were doing that, it would indicate an over-tightened condition of the steering head bolt. As I recall (please correct me if my recollection is wrong), the bearings Honda uses in the NCX's steering head are _not_ taper bearings. So, tightening them up will not slowly and gradually increase resistance as a design 'feature.' Rather, tightening them up to the point of active, felt resistance indicates they're being crushed.

 

[MZ5]

InfernoST, below are few old threads on the headshake topic. Reading through these discussions may or may not offer anything more than has been offered here.

New front tire head shake

I recently replaced both tires. I'm at around 6000 miles on the original tires and I replaced both front and back. I got Shinko 009 Ravens front and back and had them mounted and balanced by Cycle Gear. Now when I move through 35 to 45 mph the front end shakes side to side. It can be pretty...

www.nc700-forum.com

Front tire wobbling on 35 mph?

After the local bike shop changed my front tire, it started wobbling when I let go of the handlebar. But only around 35 mph. Faster or slower it doesn't or just a little bit. Is that the sign that the tire was not balanced correctly, or something else? Also, if I let go of the handlebar, to...

www.nc700-forum.com

Vibration / shaking at approx 40 mph

Hi guys, While riding today I noticed that around 40 MPH in 5th or 6th gear the handle bars / triple tree have some horrible shaking. Really noticeable when I use rear brake only. Seems to go away when around the 35 mph mark or over 45ish. I have a 2012 DCT, and this is in D mode...

www.nc700-forum.com

This last one you'll see I started. I also noted the elimination of the headshake with a change of front tire. The headshake showed up again later (that same year), as I noted in the thread immediately above these words.

Could different tires have eliminated the headshake?

This may not be in quite the right sub-forum. Sorry if it's not; move it as appropriate. At least some of us have some headshake on our NCXs. On mine, it's always manifested during deceleration, starting as I coasted down through the 40 - 35 mph area. Generally it subsided by the time I...

www.nc700-forum.com

 

[davidc83]

Hi Gang
I've been experiencing handlebar wobble for quite a while now, I originally chalked it up to the OEM supplied front tire had become scalloped. I recently replaced the front and rear tires with a different set of new dunlops at about 9000 miles and am still experiencing this front end wobble everytime I take my hands off the bars, the front wheel has new tire new bearings, seals, is balanced and not bent (checked with a dial indicator) and runs true. I check the service manual and the information supplied doesn't specifically state how tight the neck bearings spanner nuts should be, I know it has to easy but when the bike is on the center stand and I put my weight on the back of the bike to raise the front wheel off of the ground with wheel facing straight ahead the bars flop to the right side rather quickly which I find very odd. I was concidering of adjusting the spanner nuts just enough to keep the bars from flopping to the right like that. My Bike info is as follows, 2020 NC750X fully manual transmission. Does anyone have any suggestions? FYI I have tried letting go of the bars with the topcase and side boxes removed, either way it's a pretty violent wobble.

All 3 of my bikes (different makes/models), the front wheel flops to the right when I get it off the floor. I wouldn't be looking into this as part of your wobble. Numerous bikes have a wobble at slow speeds when you take hands off the bars(manufacturers state don't do that)....my Nc700x has a slight wobble at 40mph but goes away at slower or higher speeds. My C50 boulard does not have one at all, my klx250sf has a slight one at 25mph....I don't worry about either cause I know they have it and don't remove both hands from bars at same time. Neither bike has a wobble if I have at least 1 hand on the bars.

 

[InfernoST]

Can't speak to the year of yours but my 2012-2015 copy of the service manual gives torque value of 17 ft/lbs on the adjuster nut to set the correct preload on the steering stem bearings. If you decide to follow this recommendation the manual states to replace the lock washer above the adjuster nut with a new lock washer. Important because after setting the torque you continue by tightening the lock nut above the adjuster nut up to 90 additional degrees and a used lock washer can affect the torque on the lock nut.

You might have done this already but something you can try before messing with the bearings is to remove the front wheel and with the bike on the center stand set the bars straight ahead and see if you can feel a slight notch or catch when you move the bars ever so slightly to one side then releasing the bars. Without the mass of the wheel it's easier to feel this notch or you might see the bars self-center themselves instead of flopping over due to a tiny dents or notches worn in the bearings.

I'm kind of like 670cc. I have had many kinds of motorcycles over the years and some of them never exhibited this slow speed deceleration wobble and others did. The cure could be a new tire(s), changing tire pressure(s) or new bearings or keeping one hand on the bars at all times. I have had three NCs and none of them showed this behavior but then I rarely take my hands off the bars to check for it.

It is in my service manual found it further back in section 17-29 which outlines everything, this was my fault, sorry about that. All that mentioned has already been done which leads me to the neck. After realizing analyzing what's going on as my bars flops to the right rather quickly led me to this conclusion: To steer left you push left (Counter Steering)to go left which momentarily turns the bars to the right then goes goes left as long the pressure is applied, now my bikes bars flop to the right and if I apply that logic it makes perfect sense, the bars flop right initiating counter steering with no pressure the bars go left momentarily then tries to right itself to only have the bars to go right again repeating the sequence at a faster rate every cycle creating the wobble. I think tightening the neck will be the answer to this problem. If you don't agree with my analysis please sound off.

 

[potter0o]

It is in my service manual found it further back in section 17-29 which outlines everything, this was my fault, sorry about that. All that mentioned has already been done which leads me to the neck. After realizing analyzing what's going on as my bars flops to the right rather quickly led me to this conclusion: To steer left you push left (Counter Steering)to go left which momentarily turns the bars to the right then goes goes left as long the pressure is applied, now my bikes bars flop to the right and if I apply that logic it makes perfect sense, the bars flop right initiating counter steering with no pressure the bars go left momentarily then tries to right itself to only have the bars to go right again repeating the sequence at a faster rate every cycle creating the wobble. I think tightening the neck will be the answer to this problem. If you don't agree with my analysis please sound off.

With my limited experience I can only give my free internet opinion . It sounds like you have tried a number of things. Checking things out and confirming torque values seems like a good idea. Just make sure you have the washer like post 8 shares. Good luck and hope you find the source.

 

[670cc]

It is in my service manual found it further back in section 17-29 which outlines everything, this was my fault, sorry about that. All that mentioned has already been done which leads me to the neck. After realizing analyzing what's going on as my bars flops to the right rather quickly led me to this conclusion: To steer left you push left (Counter Steering)to go left which momentarily turns the bars to the right then goes goes left as long the pressure is applied, now my bikes bars flop to the right and if I apply that logic it makes perfect sense, the bars flop right initiating counter steering with no pressure the bars go left momentarily then tries to right itself to only have the bars to go right again repeating the sequence at a faster rate every cycle creating the wobble. I think tightening the neck will be the answer to this problem. If you don't agree with my analysis please sound off.

The built in caster of the front steering should tend to cancel that oscillation automatically, if the caster is ideal. As I understand it, the caster on a two wheeler comes about because the tire contact patch falls behind where the pivot line of the steering stem meets the road. This is the rake and trail stuff often mentioned in chassis specs.

What you suggest by “tightening the neck” serves to add a friction damper to the steering system. I would think if your bike’s chassis geometry is correct, a damper is not needed, but then you have the wobble problem, so it is what it is.

 

[7ncx]

It's not unusual for the steering to flop one side with the front wheel off the ground since the weight of the wheel/suspension will be on the top steering head bearing - the lower bearing supports the weight normally. Have you tried changing the fork oil? Unusual the wheel bearings replaced with low mileage. Check alignment of the rear wheel/chain and fork aligment too. Any binding in the forks? Easier to check the steering head bearings with the forks removed when changing the fork oil. Too tight/notchy steering bearings will definately cause a speed wobble and other handling issues. When installing the front wheel, tighten the front axle and make sure the left fork leg slides freely on the axle, then work the front suspension up/down then tighten the axle pinch bolt on the left fork leg all before installing the front fender. I too have a 2012 with about 30,000+ miles and while I had a few speed wobbles when new on rough road when the forks bottomed, changing the fork oil eliminated the problem. Most new bikes come with overly soft suspension. Never had any speed wobbles since then and am on the fifth or sixth set of tires and the bike tracks straight and used regularly on twisty roads. If I start to notice any slight oscillations now it is beacause the tires are worn out.

 

[InfernoST]

Concerning handlebars flopping to the right:

Shouldn't we expect that behavior, since the brake disk and caliper are on the right side? I would not expect the bars to stay straight ahead with that weight imbalance at the front axle.

***EDIT:
I'd like to expand by noting that, in my view, we should not expect (nor try to use) the steering head bearings to actively resist turning of the steering head. I believe that, if the bearings were doing that, it would indicate an over-tightened condition of the steering head bolt. As I recall (please correct me if my recollection is wrong), the bearings Honda uses in the NCX's steering head are _not_ taper bearings. So, tightening them up will not slowly and gradually increase resistance as a design 'feature.' Rather, tightening them up to the point of active, felt resistance indicates they're being crushed.

One post here indicated they are not tapered bearing like I had on previous machines which the manufacturer outlined tightening to 70 ft lbs to complete the bearing seating process then back of 180 degrees then re=adjust the until it takes 1 to 2lbs of pressure to move the bars. The problem with the NC which which someone posted is this bike doesn't use radial tapered bearings so if you tighten them too much you hose the bearing so tightening them is useless. Its either balance the the the bars using weights so the they slam to the right on their own or install a steering damper.

 

[InfernoST]

I've had 31 or 32 motorcycles, some have had the shimmied at times, others haven't. If you google handlebar shimmy at 50-40 while decelerating, you'll find posts reporting it across all brands, makes and models.

handlebar shimmy at 50-40 mph while decelerating - Google Search

Back in the 80's when I worked for a Honda shop and the new Goldwing factory dressers came out, they would wobble or shimmy quite often. Honda's solution was to bolt a big lead weight to the steering stem saying people overloading their trunks was changing the weight bias. But since it happens on naked bikes too it is surmised that it could be head bearings, tire imbalance, tire pressure, bad tire, wheel bearings, weight bias transfer and a host of other reasons. No one REALLY knows, and the reason may not be the same for every bike.

I believe in your owner's manual it will tell you to never take both hands off the handlebars, which I believe is lawyer talk for, if you take your hands off the bars, and it shimmies, and you crash, it's not our fault because we specifically told you not to take your hands off the bars.

That is a given but only did it see if the bars would wobble and sure enough they did, this should not be present on a brand new machine this is why I'm looking for the cause. thanks for your input but that answer is clearly obvious now if you had cruise control and need to quickly shake your hands then what? I know don't take your hands off of the bars.