Tire Imbalance(?) after Gotway Nikola Tire Change, NEED HELP

[rexdelmolvo]

I ride a 100v Nikola with about 940 miles on it. Got it used. The stock tire was wearing down, so at the recommendation of another rider I picked up the H666 tire to replace it. The tire change was a very difficult process, but after a couple of days and 2 popped inner tubes, I got it done. Put it all back together last night and took it out for my first ride on the new tire, and I'm having a weird issue. At first, I thought it was just the new tire getting broken in. Riding at slow speeds, I felt a slight sensation of shaking or bouncing up and down. It was subtle, and I could ignore it. Took the wheel up to my usual cruise speeds and it became a problem. At high speeds, the shaking/bouncing felt like sitting on top of a high power washing machine. It wasn't immediately affecting my stability, but I could not confidently get it to top speed like this. Here is a video demonstrating what I'm experiencing, I accelerated on a perfectly smooth bike trail while making a constant sound. You can hear the very rapid shake:

So now I have to diagnose why this is happening. This was my first time taking apart any of my wheels, so it's possible I did something wrong. I checked all the screws I messed with and reseated all the connectors. I did a little bit of research into similar problems, and started to focus on the tire's potential imbalance. I deflated the tire, and pumped it up to 10psi while massaging it, rode around on it trying to smooth it out and push each side equally into the rim, then proceeded to inflate it (multiple times) to 15/25/35/40 psi. I noticed at the unrideablely low psi's that the issue was mitigated a bit, but at any psi I'd actually ride on, the issue is still there. Once I pass 20mph, it becomes a major problem. I cannot discern what is causing the imbalance or how I can tackle it, and after multiple days of struggling with the tire change, I am nearly at my wit's end

At the request of my tire change guide, I took this video of each side of the tire, spinning it with a fully stationary camera. The tire is pumped to a little under 40psi in this video. The only visual imbalance that I notice is the lines of the bead of the tire are slightly visible on one side of the tire, and on the other, the tire digs under the rim deep enough that I can't see them. On my 16X's stock tire, I am able to see the lines of the bead all the way around the tire, with no variation. I feel like this could be the root of the problem but I don't know how to approach it. Here is the video:

Sorry for the low-ish quality, only have a phone camera to work with. I don't see anything other than the tire bead thing I was talking about.

Any help would be appreciated. I want my smooth riding Nik back If massaging and low psi's aren't working, is there a way to approach re-seating the tire that will specifically avoid this imbalance?

Edited October 15, 2020 by rexdelmolvo

[Tasku]

I summon thee @mrelwood a wizard of wheels! I think this is something you are master of?

@rexdelmolvo I feel you man, I got my first tyre to change coming up. (yikes!) I think I could replace it or dismantle the wheel enough to take it to shop, but I think I might have to balance it even after that..

Here is a video, if it is a balancing issue: 

 

Edited October 14, 2020 by Tasku
link to vid

[Tasku]

Another video about balancing a motorcycle wheel (oh gawd the end of this video) 

Edited October 14, 2020 by Tasku

[rexdelmolvo]

Man @Tasku, I didn't even know that this is something that could happen after a tire change. Is there a way I can re-seat the tire that avoids an imbalanced weight distribution?? I don't understand what part of seating the tire would cause this. It seems like it'll be an absolute bitch to figure out if I use those methods...

[Tasku]

@rexdelmolvo I would look this video too: 

But while these videos show there is many solution and ways to fix the matter. I would not duct tape weighs to wheel for one. 

Again I have not even changed my first one yet soo.. So for now, watch the videos. Check if you can identify the problem like in this last video, thats the best I can do for you.

And I think in a bit some master will help you out with best action to perform. With the help of these videos atleast confirm that the wheel is moving in imbalanced manner. Like in this video, in this post.

Good luck! (if your problem is as easy as this last video then it will be easy and quick fix)

Edited October 14, 2020 by Tasku

[rexdelmolvo]

12 minutes ago, Tasku said:

@rexdelmolvo I would look this video too: 

But while these videos show there is many solution and ways to fix the matter. I would not duct tape weighs to wheel for one. 

Again I have not even changed my first one yet soo.. So for now, watch the videos. Check if you can identify the problem like in this last video, thats the best I can do for you.

And I think in a bit some master will help you out with best action to perform. With the help of these videos atleast confirm that the wheel is moving in imbalanced manner. Like in this video, in this post.

Good luck! (if your problem is as easy as this last video then it will be easy and quick fix)

This video is similar to what I've already tried. Although, my free spin does not look nearly as janky as his. I took a video and checked, it almost looks like nothing is wrong. This is such a headache...

[Tasku]

Then you should put your wheel in stand and let the wheel be free from ground. If you move the wheel half a turn, does it stay in postition or does the wheel move the heavy part down? This would help you understand that the wheel is imbalanced.

If you can repeat the last video method of evening the inner tube, even it sounds like you done it, he balances it with 1 psi, and rides it smoothly, then when the wheel looks better apply more pressure. And make checks again. Even if you would have to repeat that process it would be way easier fix than putting weight to wheel to balance it.

 

[rexdelmolvo]

3 minutes ago, Tasku said:

Then you should put your wheel in stand and let the wheel be free from ground. If you move the wheel half a turn, does it stay in postition or does the wheel move the heavy part down? This would help you understand that the wheel is imbalanced.

If you can repeat the last video method of evening the inner tube, even it sounds like you done it, he balances it with 1 psi, and rides it smoothly, then when the wheel looks better apply more pressure. And make checks again. Even if you would have to repeat that process it would be way easier fix than putting weight to wheel to balance it.

 

The wheel does stay in position. I think the motor is too rigid to let a slight imbalance move the wheel.

[Tasku]

The other way to check is to free spin the wheel and see if it is all even when it moves. The videos demonstrate it.

If you can post what type/size of wheel you put in there (it could be wrong size too) that would help.

[rexdelmolvo]

3 minutes ago, Tasku said:

The other way to check is to free spin the wheel and see if it is all even when it moves. The videos demonstrate it.

If you can post what type/size of wheel you put in there (it could be wrong size too) that would help.

It's a 16x3 Chao Yang H-666. It's definitely the right size. I'll take a video of my free spin soon, but it is much more even than that video demonstrated.

[mrelwood]

The underlying issue you have is a noticeably dented rim. That makes seating a tire more difficult than it should be.

 You are on the right track following the lines on the tire. You should try to get them as even as possible. If you’d put the wheel on its side and a bottle upright next to the tire, you’d see that the distance from the tire to the bottle changes by maybe 2mm. That’s what causes the vibration.

1) Put the wheel on its side on a table, tire hanging over the edge of the table, and deflate the tire completely.

2) Push and pull the tire so that the lines are at the same distance from the rim, as closely as possible. Check the other side as well, from the underside. (Without turning the wheel to the other side.) Don’t try to follow the dent on the rim though. 

3) Pump the tire to 0.5 bars, and repeat 2).

4) Pump the tire to 1.0 bars and check if the tire stayed in place. If not, start over.

 Prepare for having to do this a few times around. Do a lift test and let the motor spin the wheel, and you’ll notice if the situation has improved.

 If you simply can’t get the tire satisfactorily in balance, then I’d follow the video guide I made on weight balancing the tire. @Tasku kindly posted a link to the video in his first reply.

[Marty Backe]

At ~9-seconds and ~30-seconds into the video I see what looks like a slightly bent rim.

[rexdelmolvo]

Thank you @Marty Backe and @mrelwood, I was aware the rim wasn’t perfect but wasn’t sure if it would be affecting me. During the first few attempted tire changes, we nicked it a few times with one of the tools and tried to smooth it down so that it wouldn’t pop the inner tube, which was my first major problem. I don’t think anything can be done about that other than getting a whole new motor, right? Guess I gotta see if it’s possible to work around it now.

 

EDIT: I just found this thread, seems like a very similar situation to what I’m going through, only a bit more severe!

Edited October 15, 2020 by rexdelmolvo

[rexdelmolvo]

When inspecting the damage to my rim previously, I was only paying attention to the dings on the side, so much so that I didn’t notice it is bent outwards slightly around the epicenter of the marks. I wonder if pushing this back down could end this headache..?

[mrelwood]

6 hours ago, rexdelmolvo said:

I wonder if pushing this back down could end this headache..?

Proper aligning of the tire is required with straight rims as well. But it is possible that the bend is making it very difficult.

 Be careful when bending it back though. The aluminum can crack while bending. You wouldn’t need too much though, so it should work. A few people have tried, and I suggest reading about how to do it properly. I don’t remember what were the best practices, but there are a few discussions about it.

[rexdelmolvo]

6 hours ago, mrelwood said:

Proper aligning of the tire is required with straight rims as well. But it is possible that the bend is making it very difficult.

 Be careful when bending it back though. The aluminum can crack while bending. You wouldn’t need too much though, so it should work. A few people have tried, and I suggest reading about how to do it properly. I don’t remember what were the best practices, but there are a few discussions about it.

We succeeded, somewhat. Used a hammer and a block of wood to deliver the impact without damaging the rim. I think tomorrow I have to do a little more work on the rims, but, the good news is that fixing the bent rim has helped tremendously. The wheel is rideable, but its not perfect. I barely feel the bumps until 22-ish mph, and I can go pretty close to top speed and still feel confident in my stability. I just road it to McDonald's lol. Very thankful it's not unusable, It's just not comfortable... So more work is to be done.

I still can't manage to get the bead line evenly visible/tucked in, now after my rim repairs I can barely see it around most of the wheel, but right around the valve it sticks out. I'm guessing that's the final imbalance. Following your suggestions/the processes from the videos, massaging the deflated wheel doesn't seem to do anything. It goes right back to the uneven line setup as soon as I add 5-10psi. Should I like... lubricate it? I'm so close to being done with this but I don't know what to try. Maybe taking the tire off completely and putting it back on, but... I'm worried about messing THAT up again. And then I'm back to square one so I'd like to avoid that if possible.

Thanks again for your help.

[mrelwood]

 

12 hours ago, rexdelmolvo said:

It goes right back to the uneven line setup as soon as I add 5-10psi.

Once I squeezed the tire with one hand and pumped with the other. If you don’t have three hands though, you could try to carefully strap/tie down the tire at the valve until you get some pressure in the tire.

[rexdelmolvo]

11 minutes ago, mrelwood said:

 

Once I squeezed the tire with one hand and pumped with the other. If you don’t have three hands though, you could try to carefully strap/tie down the tire at the valve until you get some pressure in the tire.

We tried that. I do have someone helping me, and no amount of squeezing the tire seems to change what it wants to do. After a lot of deflating, massaging, and banging out any dents in the rim, the last place there is any fluctuation is right around the valve. The harder valve part of the tube is pushing up against the bead or something.

 

The only thing I haven’t tried is inflating to absolute max pressure and seeing if it pops things into place. The tire says 45-55psi. Do you think lubricating the rim and the bead with soap and inflating it to 55psi could work? I was looking at the following thread and saw a similar recommendation, but they were using only 40psi (which I have pushed the wheel up to, that’s one of my rideable pressures) to accomplish this.

 

 

[.....]

dish soap and water, air that bitch up and look away as you do. I wouldnt be scared to hit 60-70psi on the damn thing. Leaving the tire in hot sunshine for a while can also help as it softens the tire. Have you deflated it and spun the tire on the rim to see if that makes a difference? Don't make the mistake and assume that ANY new tire is balanced. Tires come out of round and out of balance, rims the same. The trick is worrying about it AFTER mounted, as you balance them and look for runout as a single entity. In our shop there's 2 ways to go about things. 1.. follow guidlines.. or..   2. ignore that shit, take the chance and get shit done.  fwiw, osha was not a frequent visitor..

 

Edited October 16, 2020 by ShanesPlanet

[rexdelmolvo]

1 hour ago, ShanesPlanet said:

dish soap and water, air that bitch up and look away as you do. I wouldnt be scared to hit 60-70psi on the damn thing. Leaving the tire in hot sunshine for a while can also help as it softens the tire. Have you deflated it and spun the tire on the rim to see if that makes a difference? Don't make the mistake and assume that ANY new tire is balanced. Tires come out of round and out of balance, rims the same. The trick is worrying about it AFTER mounted, as you balance them and look for runout as a single entity. In our shop there's 2 ways to go about things. 1.. follow guidlines.. or..   2. ignore that shit, take the chance and get shit done.  fwiw, osha was not a frequent visitor..

 

Glad to see I'm not alone in having this issue on a new tire. I deflated my tire and tried a bunch of soapy water this time, pushing it into the rim and the bead with my fingers, and pumped it up all the way to 55psi. Wasn't ready to go higher than that. It helped, the bead is more even than it has been yet, but it's STILL not perfect. There's still an over-exposure of the bead line near the valve, and everywhere else it is almost invisible. I think I will have to do it a few more times. If after a few more repetitions I still make no progress, I am gonna take apart the wheel again and get the tire off, and start from scratch, but THIS time I will use a hell of a lot of soapy water for lubrication, and I think I will pop the tire in the oven at around a hundred degrees to warm it up like someone suggested.

One thing I'm curious about: when I stuck my fingers into the bead/rim, it obviously was a little tight, and as I worked the soapy water in around the tire, I noticed that when I got close to the valve, the tightness increased exponentially. Hurt my fingers too bad to work the soap water all the way in. This is also where I am experiencing the bead bulge. I imagine there would be some difference there from the rest of the tube because of the spot where the valve comes out from the tube, but should it be that high pressure? Is it possible that the valve stem area is improperly placed inside the rim/tire? If I'm right, this could be the true culprit.

I gotta get this right. I took it out again after this last adjustment, and while I could just ignore the hop, there's a voice in my head yelling "IT COULD BE SMOOTHER" at me. The voice must be appeased.

[mrelwood]

4 hours ago, rexdelmolvo said:

Is it possible that the valve stem area is improperly placed inside the rim/tire?

It is. Another, perhaps more probable cause would be the tight measures of the 16”x3” rim. I think it was the 16X that has the valve hole placed in a way that pushes the bead of the outer tire outwards. Perhaps your new tire is slightly chunkier than the original, and reveals the same issue with the valve placement.

 One thing to try might be to push the (deflated) valve stem in a bit, so that the stem reaches between the tire beads. That way as you fill the tire, the outer tire would hopefully lock in place before the inner tube pushes the valve stem out, pushing the tire beads outwards as well.

Dang, I hope I was able to explain that in a way that could be understood...

[.....]

The tube is much bulkier around the valve area. Some tubes worse than others. It being a bitch in that area to seat and get even with the rest is normal and a total pain in the ass. Some tubes are worse than others and as mrelwood put it. Some tires are tighter fit in that area. Hell, with QC being so shoddy, sometimes you run into that issue and sometimes not, with the exact same tube sizes and brands. 'heavy duty' tubes tend to be even worse if fitment is already an issue. Be ready for the soap water to dry VERY fast on a warm tire. Be liberal with it and quick about it.

Edited October 17, 2020 by ShanesPlanet

[rexdelmolvo]

1 minute ago, mrelwood said:

It is. Another, perhaps more probable cause would be the tight measures of the 16”x3” rim. I think it was the 16X that has the valve hole placed in a way that pushes the bead of the outer tire outwards. Perhaps your new tire is slightly chunkier than the original, and reveals the same issue with the valve placement.

 One thing to try might be to push the (deflated) valve stem in a bit, so that the stem reaches between the tire beads. That way as you fill the tire, the outer tire would hopefully lock in place before the inner tube pushes the valve stem out, pushing the tire beads outwards as well.

Dang, I hope I was able to explain that in a way that could be understood...

Mostly, haha. I will try to mess with that a bit tomorrow, I've retired for the night.

9 minutes ago, ShanesPlanet said:

The tube is much bulkier around the valve area. Some tubes worse than others. It being a bitch in that area to seat and get even with the rest is normal and a total pain in the ass. Some tubes are worse than others and as mrelwood put it. Some tires are tighter fit in that area. Hell, with QC being so shoddy, sometimes you run into that issue and sometimes not, with the exact same tube sizes and brands. 'heavy duty' tubes tend to be even worse if fitment is already an issue. Be ready for the soap water to dry VERY fast on a warm tire. Be liberal with it and quick about it.

Oh, you KNOW I will be soaping that thing like my life depends on it. I don't know why I wasn't using any in the first place, frankly. Got the tip a few times and ignored it. And boy am I paying for it now hahaha

Wish me luck tomorrow!

[rexdelmolvo]

Did a little inspection of the valve stem area. Now I’m certain this is the core issue, but I have no idea what do about it...

The valve stem & hole are positioned in such a way that it’s blocking the bead from going all the way in like it needs to. There is a little bit of space behind the valve stem that it could maybe occupy if I could manage to angle the stem into the valve hole differently, but I had a hard time getting the valve stem in as it is. I don’t know how much differently I could do it. Also, ALL of my air pumping instruments require the stem to be lifted a bit in order to pump as they’re too thick to fit in the valley of the rim (including my extenders!), so I wonder if the manipulation of the valve stem could be affecting the seating process. By lifting it I usually am pushing it a bit inwards, I think.

After messing with the valve, I just attempted soapy reseat #2, and the bead line looks the best it has but it’s still not perfect. About to take it for a test run.

EDIT: It looked good, it does NOT feel good. I’m getting so sick of this... 

Edited October 17, 2020 by rexdelmolvo

[.....]

time to try another brand of tube?