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-   -   Do you balance (not true) your wheels? (https://www.bikeforums.net/showthread.php?t=1247050)

yaw 02-19-22 03:40 AM

Do you balance (not true) your wheels?
 
I am wondering how many riders balance (not true) their wheels, or have purchased wheels that came balanced with counterweights to offset the heavy spot.

The Aeolus Elite 35 TLR carbon wheels that came with my bike created a noticeable rear wheel vertical wobble when spinning the pedals fast on the stand, which can also be felt when holding the bike up by the seat, and the front wheel rotated quickly with the valve dropping to the bottom when lifting the front up. I would think that this is the case with most wheels out there, some more extreme than others depending on wheel material/construction, weight/size of the valve stem, and so on. Whilst the weight of a rider will not cause the rear up and down wobble to present any real issues and any 'flywheel gains' are extremely marginal, I think the oscillation in the front when rolling fast may contribute to a risk of speed wobbles. This aside, it somehow seems right to me that a contraption that is all about two wheels spinning quickly should be a balanced and smooth system.

For those interested, the procedure is quick, cheap and simple and whilst it can be argued endlessly, the additional weight won't matter in practice, and even in fine print theory the acceleration effort is offset through momentum. The following assumes a modern rim with a wide enough inner diameter and channel so that the weights can be placed on the inside, rather than any external attachments that mess with the look and aerodynamics of the wheel.

1. Determine the heavy spot on the wheel by lifting the front wheel off the ground and experimenting with where it wants to settle at the bottom by letting it go from a few orientations.
2. Mark the exact opposite of the heavy spot at the highest point of the settled wheel.
3. Stick varying amounts of blu tack or similar to the marked spot until the wheel no longer moves away from any rotation it is set to rest in.
4. Weigh the exact amount of blu tack as accurately as you can. You may need 3.4g, you may need 17.8g, who knows.
5. Purchase a few 'golf club adhesive lead weights' (not tape but the little flexible lead slabs with an adhesive side) and rim tape.
6. Determine how many lead weights and what amount of rim tape (make sure it is enough rim tape to cover the length of the required lead weights all aligned in a row) make up your target weight.
7. Remove the wheel and take the tyre/tube off and place a lead strip inside the wheel channel (where the tube lives) exactly on the marked spot and the others, if needed, evenly each side of the central weight.
8. Cover it up with the appropriate length of rim tape, but do make sure that the weight of the rim tape is considered as part of the target weight as it is significant in this case.
9. Pop tube/tyre back on, the tyre ideally in the same orientation as before (but we already know you will keep the tyre brand over the valve anyway), and test whether the trick worked by holding at the hub to see if it stays put wherever you stop it.
10. Mount the wheel and repeat on the other one, the same weight will probably work closely enough if it is the same wheel as the front. Just confirm with the same amount of blu tack as before and vary if needed.

I needed a whopping 12.85g per wheel, or 3 of the little golf lead strips with a length of rim tape that covered the strips and then some more. I just placed the lead weights on the existing rim tape and then taped over the top of it all, these things are so flat that they can be sandwiched by the rim tape and still keep a low profile. The same weight worked on both wheels with 28mm GP5000s on the rear and 25mm on the front, so tyres seem to be even enough. Now the wheels stay wherever they are set when lifting the bike up and the bounce is gone when cranking it up. This proof of improved balance aside, it also appears that the whirr from the hub engagement points now sound more even when coasting fast. Otherwise it rides as before but with a little added confidence on fast descents - yeah it's a mostly subjective undertaking.

Thoughts?

50PlusCycling 02-19-22 05:56 AM

I balance the front wheel only. So long as the rear wheel is true, and not out-of-round, I don’t worry about balancing it. But I’ve experienced “death wobbles” on some bikes on fast descents. My method of balancing the wheel is to use the sensor magnet for my cycle computer. It can be moved from spoke to spoke, inward or outward to fine-tune the balance.

yaw 02-19-22 06:10 AM


Originally Posted by 50PlusCycling (Post 22414240)
I balance the front wheel only. So long as the rear wheel is true, and not out-of-round, I don’t worry about balancing it. But I’ve experienced “death wobbles” on some bikes on fast descents. My method of balancing the wheel is to use the sensor magnet for my cycle computer. It can be moved from spoke to spoke, inward or outward to fine-tune the balance.

Yes the front would definitely be the priority. Pretty good if you can actually balance your wheel completely through nothing more than carefully placing the magnet - do you know how much these usually weigh?

shelbyfv 02-19-22 06:30 AM


Originally Posted by yaw (Post 22414214)
I am wondering how many riders balance (not true) their wheels, or have purchased wheels that came balanced with counterweights to offset the heavy spot.

The Aeolus Elite 35 TLR carbon wheels that came with my bike created a noticeable rear wheel vertical wobble when spinning the pedals fast on the stand, which can also be felt when holding the bike up by the seat, and the front wheel rotated quickly with the valve dropping to the bottom when lifting the front up. I would think that this is the case with most wheels out there, some more extreme than others depending on wheel material/construction, weight/size of the valve stem, and so on. Whilst the weight of a rider will not cause the rear up and down wobble to present any real issues and any 'flywheel gains' are extremely marginal, I think the oscillation in the front when rolling fast may contribute to a risk of speed wobbles. This aside, it somehow seems right to me that a contraption that is all about two wheels spinning quickly should be a balanced and smooth system.

For those interested, the procedure is quick, cheap and simple and whilst it can be argued endlessly, the additional weight won't matter in practice, and even in fine print theory the acceleration effort is offset through momentum. The following assumes a modern rim with a wide enough inner diameter and channel so that the weights can be placed on the inside, rather than any external attachments that mess with the look and aerodynamics of the wheel.

1. Determine the heavy spot on the wheel by lifting the front wheel off the ground and experimenting with where it wants to settle at the bottom by letting it go from a few orientations.
2. Mark the exact opposite of the heavy spot at the highest point of the settled wheel.
3. Stick varying amounts of blu tack or similar to the marked spot until the wheel no longer moves away from any rotation it is set to rest in.
4. Weigh the exact amount of blu tack as accurately as you can. You may need 3.4g, you may need 17.8g, who knows.
5. Purchase a few 'golf club adhesive lead weights' (not tape but the little flexible lead slabs with an adhesive side) and rim tape.
6. Determine how many lead weights and what amount of rim tape (make sure it is enough rim tape to cover the length of the required lead weights all aligned in a row) make up your target weight.
7. Remove the wheel and take the tyre/tube off and place a lead strip inside the wheel channel (where the tube lives) exactly on the marked spot and the others, if needed, evenly each side of the central weight.
8. Cover it up with the appropriate length of rim tape, but do make sure that the weight of the rim tape is considered as part of the target weight as it is significant in this case.
9. Pop tube/tyre back on, the tyre ideally in the same orientation as before (but we already know you will keep the tyre brand over the valve anyway), and test whether the trick worked by holding at the hub to see if it stays put wherever you stop it.
10. Mount the wheel and repeat on the other one, the same weight will probably work closely enough if it is the same wheel as the front. Just confirm with the same amount of blu tack as before and vary if needed.

I needed a whopping 12.85g per wheel, or 3 of the little golf lead strips with a length of rim tape that covered the strips and then some more. I just placed the lead weights on the existing rim tape and then taped over the top of it all, these things are so flat that they can be sandwiched by the rim tape and still keep a low profile. The same weight worked on both wheels with 28mm GP5000s on the rear and 25mm on the front, so tyres seem to be even enough. Now the wheels stay wherever they are set when lifting the bike up and the bounce is gone when cranking it up. This proof of improved balance aside, it also appears that the whirr from the hub engagement points now sound more even when coasting fast. Otherwise it rides as before but with a little added confidence on fast descents - yeah it's a mostly subjective undertaking.


Thoughts?

Apparently at least two....:foo:

look566 rider 02-19-22 07:36 AM

Interesting post! Never gave much thought as this issue has never come up on rides. Have never really noticed wheel rotating as you describe. Will have to check bikes and see!

Were the wheels checked with tires and tubes installed? I could see the presta valve be part of issue. Not familiar with Aeolus Elite 35 TLR wheels outside if web search. Wonder if they have manufacturing process that creates heavy spots.

woodcraft 02-19-22 11:18 AM

I have, as I share the speed wobble concern.

Sheet lead, used for building flashing, cut with scissors, form to rim, tape in place. When satisfied, glue w/ spray adhesive or contact cement & cover with electrical tape. These are tubular wheels, so not messing with the rim bed.

In previous BF discussions, the idea has been largely scoffed at.

smashndash 02-19-22 11:41 AM

Right. On BF, you're largely going to get scoffed at for thinking about stuff like this. This forum is mainly populated by curmudgeons who don't care much for the finer aspects of cycling. This is despite the fact that many deep wheels come with counterweights stock and some pro teams balance their wheels too (don't quote me on that).

That being said, I haven't balanced my wheels, and don't really feel the need to. I very, very rarely go over 45mph and I don't feel unstable under that speed. Even at 50mph, I've never had anything close to speed wobble.

rm -rf 02-19-22 11:52 AM

It's pretty noticeable when spinning on the bike stand. Not noticeable on the road.

I did feel a slight vibration on a newly paved, glass smooth road, downhill over 30 mph. Even then, a really subtle effect.

Speed wobble
The wheel balance is an up-and-down force, not a side-to-side force. I think any speed wobble contribution would be swamped by other speed wobble sources, like stiff arms and hands and fork+frame resonances.

at 30 mph, the bike covers 44 feet per second. That's at least 7 revolutions per second for the wheel. Faster than a typical speed wobble, I think. And if it doesn't match up with the bike+rider resonance frequency, it won't worsen a wobble.

tomato coupe 02-19-22 11:53 AM

Do you balance (not true) your wheels?

No.

Iride01 02-19-22 12:48 PM

No.

Never have I ever felt anything remotely out of balance on my bike wheels. There just isn't enough mass to a typical road bike wheel at the outer circumference to make that a factor for the entire weight of the bike and rider.

The last time I ever felt something that seemed like a bicycle wheel being out of balance, it turned out to be a tire that wasn't seated properly to the witness lines.

Jack Tone 02-19-22 01:36 PM

Why not just remount the tire 180 degrees from where it is and try it. I personally wouldn't put anything in the rim channel of a tube tire.

sdmc530 02-19-22 01:59 PM

Park Tool's Calvin did a video on this topic, I will have to see if I can find it. It was really interesting but if I remember it correctly in his opinion it was a waist of time and effort.

They did some experiments and showed why they thought it wasn't worth the effort at all. I will post it if I can find it, but it was a really good watch.

sdmc530 02-19-22 02:14 PM

Found it;




Groasters 02-19-22 02:29 PM

If ever I find myself with enough spare time on my hands to balance my bike wheels, I'd choose to do a thousand things other than balance my bike wheels.

As someone has quoted, at 7 revolutions per second at 30+mph, with the tiny amount of mass/momentum of a lightweight bike wheel/tyre combination, with a big heavy human keeping the whole setup stable, compared to a heavy car wheel/tyre rotating at say 60mph, it adds up to approximately nothing.

It reminds me of folks that try to realign their cassette because they notice a slight wobble while freewheeling when the bike is in the work stand. A similarly fruitless use of precious time. Life's too short.

epnnf 02-19-22 04:49 PM

I balance whenever I replace brake pads. But I use little spoke lights that are very lightweight. I doubt if its making any difference.

shelbyfv 02-19-22 05:36 PM


Originally Posted by sdmc530 (Post 22414663)

Thanks.:thumb:

Sy Reene 02-19-22 05:54 PM

I found that without my tube valve cap, the wheel is unbalanced. Put back on, it's balanced.

yaw 02-19-22 06:13 PM


Originally Posted by woodcraft (Post 22414512)
I have, as I share the speed wobble concern.


Sheet lead, used for building flashing, cut with scissors, form to rim, tape in place. When satisfied, glue w/ spray adhesive or contact cement & cover with electrical tape. These are tubular wheels, so not messing with the rim bed.


I never had tubulars but putting it on externally would be a bit of a barrier for me. Your solution sounds rather permanent too, did you manage to keep it low profile and tidy looking, no aero concerns?



Originally Posted by smashndash (Post 22414538)
Right. On BF, you're largely going to get scoffed at for thinking about stuff like this. This forum is mainly populated by curmudgeons who don't care much for the finer aspects of cycling. This is despite the fact that many deep wheels come with counterweights stock and some pro teams balance their wheels too (don't quote me on that).


That being said, I haven't balanced my wheels, and don't really feel the need to. I very, very rarely go over 45mph and I don't feel unstable under that speed. Even at 50mph, I've never had anything close to speed wobble.


I haven't purchased enough wheels in my time to know how common the counterweights are, but I know a local wheel maker includes an internal counterweight in their upgraded line of wheels. Then I realised how bouncy mine were and the solution seemed simple enough to just do preventatively. I do some climbs with long fast descents and I just preferred to cut down on any such risk with the little effort it took to do this. But I have not felt an outright need based on a ride experience on the current setup either.



Originally Posted by Jack Tone (Post 22414634)
Why not just remount the tire 180 degrees from where it is and try it. I personally wouldn't put anything in the rim channel of a tube tire.


The tyre does not seem to matter enough in this case, it's all about the wheel. You won't balance out that 60mm valve stem by relying on tiny rubber weight variations along a tyre. On carbon I guess it will always be the valve, on aluminium it could be some join line/welds also. When I checked the wheel balance before putting the tyre back on, it was exactly the same as with the tyre mounted.


As far as having something sitting in the channel, it's low profile and held in place/smoothened out by rim tape so it can't cut the tube, so the tube will just sit around it and hold it into place under pressure.



Originally Posted by sdmc530 (Post 22414650)
Park Tool's Calvin did a video on this topic, I will have to see if I can find it. It was really interesting but if I remember it correctly in his opinion it was a waist of time and effort.


They did some experiments and showed why they thought it wasn't worth the effort at all. I will post it if I can find it, but it was a really good watch.


Thanks, will have a look! I did this surgery at the same time as a tyre swap so the additional effort was really minimal.



Originally Posted by Groasters (Post 22414680)
If ever I find myself with enough spare time on my hands to balance my bike wheels, I'd choose to do a thousand things other than balance my bike wheels.


(...) A similarly fruitless use of precious time. Life's too short.


You must be very busy because ordering the supplies online takes a minute, determining the required weight another minute, and you don't even have to take the whole tyre/tube off to place the goodies in the right spot. Alternatively, just wait for a tyre swap and then it's probably another minute per wheel to put the weights in and tape them up. You make it sound like it takes hours when it's really a matter of minutes.

yaw 02-19-22 06:41 PM


Originally Posted by Sy Reene (Post 22414853)
I found that without my tube valve cap, the wheel is unbalanced. Put back on, it's balanced.

I suggest you experiment with different valve cap brands to further dial it in!

woodcraft 02-19-22 07:26 PM

Looks OK IMO.
https://cimg7.ibsrv.net/gimg/bikefor...f1dacc50c.jpeg

Seattle Forrest 02-19-22 09:21 PM

Never done it. I had a bike that got speed wobbles at fairly low speeds. Never experienced it on my current bike with either wheel set. I have a pair of Enve SES wheels that wind up with the same spot at the bottom when I hang the bike; they know a lot more about this than I do and don't consider it important, I'm ok with that.

​​​​​

Random11 02-19-22 09:35 PM

I've never even thought about it. Now I have to go check my wheels to see if they are out of balance.

sdmc530 02-19-22 09:41 PM


Originally Posted by Random11 (Post 22415046)
I've never even thought about it. Now I have to go check my wheels to see if they are out of balance.

please don't

big john 02-19-22 10:24 PM

I didn't know it was a thing and I'm as old as dirt.

tempocyclist 02-19-22 10:48 PM

I can definitely "notice" the out-of-balance when spinning a wheel in the workshop (either freely or wheel still on the bike) but I've never noticed it while out riding.

Wheel balancing is one of those things I think about from time to time, but have never bothered to experiment with. Maybe one day.



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