New front tire head shake

[Floowid]

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 slight, but if I remove my hands it is very obvious and probably pretty dangerous. I notice there is a lot of weight, more than I would think is usual, and it is opposite the valve stem. I've tried various pressures from 32 to 40 pounds and it seems to make no difference. The first time I called Cycle Gear they told me to give it a couple weeks to "break in." I did that but if anything it seems worse. It is just bad enough that I don't feel completely comfortable riding and its not fun. I called them again and I think they are trying to brush me off. I don't want this to be a Cycle Gear bash, I'm more wondering if anyone else has had this problem, if there is something else I should check, any suggestions?

 

[the Ferret]

Its a pretty common problem, however if it wasnt there before I'd say its the tire or the tires balance.

Oh and the manufacturers will tell you never to take both hands off the bars

 

[670cc]

I would first inspect the tire. Raise the front so the wheel can be spun freely. Rotate the tire and check for runout, laterally and radially. See if the tire carcass seems twisted. Look at the tire bead all the way around both sides and see if it appears seated evenly.

If you want to verify the wheel balance, it’s pretty easy to do with a balance stand, as you might buy at Harbor Freight.

If you were able to demonstrate runout in the tire, you could go back to Cycle Gear, show them, and demand a replacement tire. If you are able to demonstrate imbalance, you can just rebalance it yourself with the balance stand, or ask Cycle Gear to rebalance the wheel.

Did Cycle Gear remove and reinstall the wheels? Make sure the axle spacers are correctly installed in the right places. Verify axle torque. Also, it wouldn’t likely cause head short as we, but be sure the rear brake caliper mount bracket slot is over the pin on the inside right swingarm. .

I have had six different front tires on my NC, including a Shinko Raven, all (except the factory original) I mounted and balanced myself. I have never had head shake on the motorcycle. Perhaps you got a bad tire or bad installation work.

 

[MZ5]

670cc has good advice. Our experiences are very different, however. I have never had a tire that completely and always _stops_ the headshake. Some have been worse than others, and load and load balance on the bike make a huge difference. Nevertheless, the NCX as a model of motorcycle tends to shake its head a bit. As you see, not all individual bikes do it.

Check as Greg suggests, and keep some pressure on Cycle Gear if the bike definitely never shook before AND you haven’t changed loading or suspension setup at all.

 

[CamaroEric]

Mine is absolutely horrid with head shake since I put 009's on also. Tire and wheel are dead true and perfectly balanced, I theorized that it has something to do with the center groove.

But I've managed to live with it for some 12000 miles and tend not to ride with both ands off the bars. My winter plan this year is to rebuild the front end anyway and see if that helps.

 

[670cc]

One possible cause of headshake, based mainly on my experience on a prior motorcycle model, is loading down the rear of a softly sprung bike. The change in weight bias and steering geometry can make the front end behave like a wobbly shopping cart wheel. I run an Ohlins rear shock/spring on my NC and it doesn’t sink down when loaded like the stock shock did. Whatever the reason, there’s no headshake on my NC, with Ravens or any other tire.

 

[dduelin]

I’ve had bikes prone to head shake and familiar with it but none of my NCs have had it occur yet.

As part of a tire promotion Cycle Gear mounted the current front Michelin Road 5 on the RT. I took the wheel in and let them mount the new tire. When I picked up the wheel there were two parallel strips of 1/4 oz weights about 6 or 8”long. I forget now the exact amount but it was 4 or 6 oz of weight. I said no way a MC tire ever takes that much weight but the guy said that’s what it took and shrugged his shoulders. I didn’t argue but when I left I went to my friend’s house that usually mounts my tires. We stripped the weights off and rebalanced the wheel with .5 oz of weight. I would press Cycle Gear to take another look at it and especially since it did not do it beforehand.

 

[the Ferret]

One possible cause of headshake, based mainly on my experience on a prior motorcycle model, is loading down the rear of a softly sprung bike. The change in weight bias and steering geometry can make the front end behave like a wobbly shopping cart wheel. I run an Ohlins rear shock/spring on my NC and it doesn’t sink down when loaded like the stock shock did. Whatever the reason, there’s no headshake on my NC, with Ravens or any other tire.

In the early 80's I was working for a Honda dealer and the new Goldwings were fine until people started putting on trunks and loading them up with weight. Then the bikes developed headshake or wobble. Honda finally came out with this giant lead weight to affix to the frame headstock behind the fairing, and limiting weight on luggage rack and trunk to cure it.

 

[762x54]

I call BS on "wait two weeks for it to break in". If there is a colored dot on the tire it should be positioned at the valve stem. The local Cycle Gear balances tires
by the static method which is highly dependent on the skill of the technician. I would take the complete bike to a dealer who employees factory certified techs
and has a computer balancer and have them inspect and rebalance the tire. If they find something amiss be sure to save the receipt for the work they do and
try to get Cycle Gear to reimburse you.

 

[670cc]

I call BS on "wait two weeks for it to break in". If there is a colored dot on the tire it should be positioned at the valve stem. The local Cycle Gear balances tires
by the static method which is highly dependent on the skill of the technician. I would take the complete bike to a dealer who employees factory certified techs
and has a computer balancer and have them inspect and rebalance the tire. If they find something amiss be sure to save the receipt for the work they do and
try to get Cycle Gear to reimburse you.

I agree with you except for the part about locating the tire dot at the valve stem. The tire dot should actually be located at the heaviest spot on the rim, which in my own testing of 4 different NC wheels and 4 different Goldwing wheels, is very likely NOT at the valve stem. I put my bare wheels (with valve stem and cap installed) on a balance stand and found that on 7 out of 8 different wheels, the heavy spot is not at the valve stem, rather it’s often 90 degrees or more away. I permanently punch mark the heavy spot of the rim for future tire mountings.

What a shop should do is check and mark the actual heavy spot of the rim and put the tire dot there. If they don’t, they may as well ignore the dot and throw the tire on at any random place.

This is one reason I prefer mounting my own tires, since shops usually don’t do it right.

 

[Saturday Morning]

@Floowid, I'll chime and add that I've had this exact same experience before with a new front tire purchased and balanced at Cycle Gear. I took the tire back, they rebalanced it and the problem was solved.

Here is the bedtime story version with details: I've bought (7) new tires from CG and overall been a happy camper. They have a store close to work and the gentlemen that mounts and balances tires there has been doing it for years. However, on the set before my current tires I noticed a wobble in the front tire on deacceleration through certain speeds. I double checked the mounting and static balance as best I could, I removed and reinstalled the wheel just to be safe but there was no change or improvement. I called the store and told them about the issue and that I would be bringing the tire back in. The gentleman in the store invited me to the back to observe and dismounted the tire completely from the rim. We each inspected it closely looking for any damage or deformation but found nothing wrong. He remounted the tire and rebalanced it (They do use a computerized balancing machine and I observed the entire process) - I took the tire back home to reinstall with the understanding that if It continued to wobble, I would bring it back and we would make a warranty claim with the mfr. The tire rode just fine after the reinstallation with no detectable wobble. I called the store the next day to let him know that the tire was riding great now and thanked him for the extra time to dismount, inspect, remount and rebalance the tire. Moral of the story is don't over analize it too much, stuff happens, sometimes things don't go smoothly. Work with them and let them have a chance to make it right.

Good Luck,
-Saturday

 

[TacomaJD]

One possible cause of headshake, based mainly on my experience on a prior motorcycle model, is loading down the rear of a softly sprung bike. The change in weight bias and steering geometry can make the front end behave like a wobbly shopping cart wheel. I run an Ohlins rear shock/spring on my NC and it doesn’t sink down when loaded like the stock shock did. Whatever the reason, there’s no headshake on my NC, with Ravens or any other tire.

I'm leaning towards geometry being a big culprit. Both my NC's have rear shock at max preload so rear sits higher than stock, and between stock tires on my 2016, and then a mix of Michelin Road 5's, Road 4's, and Dunlop Q3+ on both the 2013 and the 2016, I've never had the first bit of head shake on either bike. Doesn't matter if I'm running 60 or 20, I can let go of the bars at anytime and it runs true with zero shake. But who knows?

 

[MZ5]

Geometry unquestionably matters a lot, which is part of why load and load balance matters.
Compared with when the bike was new, I increased preload on the factory shock in order to get sag right. That helped.
On my months-long trip to a temporary work location one summer, when I had the bike fully laden with all my things for the duration, the headshake was much more pronounced.
Later on, I raised the fork tubes in the triple clamp a bit. That wasn’t because of headshake, but that also reduced the effect.

The headshake is essentially always on deceleration, and most always in a certain speed range centered around 35mph-ish, let’s say, for all of us whose bikes shake their heads.

Under the right conditions, I could get Wiley to shake enough to bang the bars against the stops. It wasn’t tough to stop it, though, and it wasn’t going to crash. Happened with every brand and model of tire I had on the bike, to some degree. I don’t run the factory shock any more, and combined with everything else it’s been quite a while since I’ve noticed anything more than the tiniest hint of shake.

I still think a re-try with the front tire should reduce or eliminate the condition OP has experienced, but it _may_ not.

Proper suspension setup is very important on a motorcycle; FAR more important than most any car (or motorcycle?) driver today would ever imagine.

 

[Havok]

I have a 2020 NC 750 Dct with original Dunlop tires 4k miles and there is zero head shake. My opinion something is not right.

 

[Bskicrash1]

I’m saying this just because it hasn’t been stated yet. The NC fork has a captive fork bolt for fork alignment. If the front axle and fork isn’t aligned and then the pinch bolt is torqued, the front end Can, but not always, develop a shake. I would loosen up the pinch bolt, hold the front brake firmly, bounce the front end several times, never taking pressure off the front brake, then tighten the pinch bolt, this will allow the forks to align properly. This has in the past, fixed my wobble and front end pull when on the front brake hard.

 

[CamaroEric]

I loosened all the lower fork bolts last night, bounced, torqued the axle to 55lb-ft, and retightened all the little bolts. It gave a partial reduction in low speed head shake but overall the shake frequency and magnitude is higher at higher speeds... likely in relation to the added rotational energy of the front wheel.

If time permits this weekend, I will check/grease the bearings and perform the procedure again and also include the triple tree clamps.

 

[showkey]

My VFR1200x had hands off decel head shake with the last replaced tire. Prior tire had no shake.
I knew it was the new tire. This was DIY tire install. I did not try to get the tire replaced by the manufacturer.
This time was a very specific decel speed 30-33 mph decel was where the shake occurred. Above that speed no shake. Below the shake diminished as the speed dropped. While that speed sensitivity is not uncommon this was more abrupt.

I was in the motorcycle industry for many years. I understand and have seen the problem many times.
But……..I completed all the standard fixes or adjustments including:

reseat tire bead
removed tire and reinstall
move tire on the rim
redo the balance multiple time
realign the forks
Check the steering head bearing

Used the tire for 4000 miles with no change. It still had the shake.

While the tire was not worn out. Replaced the tire……new tire no hands off head shake.

There are many prior posts on this forum, other forums for many models and many manufactures, many articles that addresses the hands off head shake Phenomenon.

Think many bikes have the hands off shake……that is never seen, found or experienced as it takes hand off the bars and decel to get the shake started.

 

[showkey]

Please do NOT confuse high speed wobble and or weave with hands off the bars decel shake.

That info does not belong in this thread or topic.

 

[MZ5]

The video shows a condition unrelated to anything the NCX does, regardless whether a bad tire or something about the motorcycle causes it.

 

[Floowid]

Winter and some personal health issues have kept me off the bike for a while, but last week I pulled it out from under all the crap in the garage and got to troubleshooting. I tried checking the alignment of the rear tire, I checked the sag and rear spring preload. I took the tire off several times and reseated the bearings and spacers. Did the thing with the captured axle bolt and the bouncing on the front brake. The last time I did this I tightened the axle more than I would normally, bounced my brains out, and tightened the capture bolt down too tight as well. It's the best it has been but still there up through 40-45mph a little but definitely back down from 50-40. Small side to side wobble. It probably wouldn't kill me at this point, but man I have tried everything and none of it mattered with the old tire...

So I just ordered a new Michelin Road 5 front tire and I am going to try that. If that is it, I'll be happy to lose out on one $96 front tire and a lesson in being frugal. If not, I have $300 dollars worth of new front tires and a problem still to chase down.

I'm not too sad to see the Shinko go for one local problem it exacerbates. We have the bulk of our freeways made of concrete, with lines (for grip?) running miles and miles, and none of them straight. The center groove on the Shinko just loves to pick a line and follow it. The couple times I have dared take it on the freeway with this tire I have disliked the inclination to follow the ever-present concrete freeway lines.