Johan Bornman Posted January 5, 2008 Share The Fulcrum Racing Speed Carbon Fibre wheels comes with all black spokes except it has two silver spokes. These spokes are opposite the valve hole and are thicker than the rest to ensure that the wheels are balanced properly. The siver spokes are just there as a reminder that the are heavier (thicker). On normal alloy wheels metal is removed by CNC machining to ensure they are balanced. This cannot be done with Carbon Fibre. The silver spokes is the indicator of a process called "Dynamic Balancing" according to Paul Butler of Fulcrum. I normally situate magnets for speedo pickups opposite the valve hole just in case. Ja, and the tooth fairy has two large wings for forward propulsion and two smaller ones for lateral movement. On fast-moving vehicles wheels are balanced after the tyres are fitted since tyres and tubes have a bigger balance aberation that wheels and hubs on their own. On slower vehicles like bicycles, wheelbarrows and pizza cutters, there is no need to balance a wheel. Fulcrum is silly trying to balance their wheels since they're not solving an existing problem but rather just looking for a marketing edge. However, I have no doubt that you'll argue with me and therefore I challenge you to explain to us how an unbalanced wheel presents on a unsuspended vehicle like a road bicycle. That's all I ask of you. Putting two thicker spokes on a wheel is a very, very bad idea. Thicker spokes have huge longevity problems. Also, I find it quite amusing that the two thicker spokes just so happen to be the right weight to compensate for the imbalance. Why not sometimes three or even four? there is after all no consistency in the rim extrusion process. Anyone who has ever adjusted a hub's cones the right way will know that a wheel's heavy section is not necessary the valve stem area but could be anywhere. On four of our six bikes this is elsewhere than at the stem hole. What is alloy? Oh I see, you think alloy means aluminium. Well, brass, tin, bronze and indeed steel, are all alloys. tsk tsk tsk. Further, metal is never removed by CNC machine for balancing, metal is removed by a dumb lathe to remove the welding ridge and the anodising on the braking surface. There is no balancing function here. Perhaps you should visit a rim factory one day and have a look. Also, next time you have a trashs rim, cut it into exactly 100mm sections and weight them all. You'll find a huge discrepancy. Sidewall machining or not. Dynamic balancing? That's a nice big word for those marketing pamphlets. All that means is that something was balanced whilst in was spinning, as they do on car wheels, fans, propshafts and just about everything else. The only time you do a static balance is on something like a model airplane propellor you balance in a little jig you make in your garage. Parthian shot: balancing wheels on a bicycle is hocus pocus. Link to comment Share on other sites More sharing options...
Guest Big H Posted January 6, 2008 Share What is alloy? Oh I see' date=' you think alloy means aluminium. Well, brass, tin, bronze and indeed steel, are all alloys. tsk tsk tsk. Oh no !!!!!! he is not only a "expert" on wheels he is a metallurgist as well!!!!!!! Further, metal is never removed by CNC machine for balancing, metal is removed by a dumb lathe to remove the welding ridge and the anodising on the braking surface. There is no balancing function here. Perhaps you should visit a rim factory one day and have a look. Also, next time you have a trashs rim, cut it into exactly 100mm sections and weight them all. You'll find a huge discrepancy. Sidewall machining or not. Dynamic balancing? That's a nice big word for those marketing pamphlets. All that means is that something was balanced whilst in was spinning, as they do on car wheels, fans, propshafts and just about everything else. The only time you do a static balance is on something like a model airplane propellor you balance in a little jig you make in your garage. Parthian shot: balancing wheels on a bicycle is hocus pocus. [/quote'] Ah my friends..... we have mr J Boreman (self taught wheelbuilder) vs the ESTABLISHED LARGE FIRMS WHO DESIGN MANUFACTURE AND SUCCESSFULLY SELL THEIR PRODUCTS WORLD WIDE The Dynamic Balancing and the information in my posting came from this. Mr Boreman is now even doubting an esteemed cycling magazine such as Procycling as well as the established company, Fulcrum Wheels. Why does this man protest so much??????!!!!!! Ekke wonner maar net!!!!!! Link to comment Share on other sites More sharing options...
Edition 507 Posted January 8, 2008 Share Ah, Mister Boreman, you are normally technically correct, show tremendous insight and are very knowledgeable on the topic of bikes, and I normally agree with your view point wholeheartedly. However, I take exception to your comment that wheel balancing is hocus pocus and just marketing bullsh1t. I have a pair of <?:namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" />Easton carbon wheels. Beautifully balanced sans a tubular, but put a tubby on with a valve extension and it is no longer beautifully balanced and vibrates like a tumble dryer with a brick in it. To top it all I have pimped my wheels with skull valve caps weighing in at a whopping 4 grams each, which admittedly aggravates the problem. I posted a topic on the tech shack forum a while back for wheel balancing advice, and like yourself, the majority of hubbers thought I was being daft. I laugh in the face of their ignorance. I have now balanced my wheels with a motor cycle lead weights which I grooved and crimped to a spoke at the opposite end of my valve. For most bicycle riders this would not ever be a problem as their fun rider capabilities rarely allow them to see speeds of over 30 kph, but for the rest of us who are ?real? cyclists , well balanced wheels are not just marketing hype. <?:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />Pictures can follow on request. Link to comment Share on other sites More sharing options...
Brakkies Sport Fotos Posted January 8, 2008 Share hello carbonboy, dont fall into the trap by thinking funriders cannot see 30km/h. If thats what you think, than maybe just stick to your weights on spokes and leave the funrider out of your "findings" popeye2008-01-08 08:19:44 Link to comment Share on other sites More sharing options...
Johan Bornman Posted January 8, 2008 Share Snip snip snipppp To top it all I have pimped my wheels with skull valve caps weighing in at a whopping 4 grams each' date=' which admittedly aggravates the problem. I posted a topic on the tech shack forum a while back for wheel balancing advice, and like yourself, the majority of hubbers thought I was being daft. I laugh in the face of their ignorance. I have now balanced my wheels with a motor cycle lead weights which I grooved and crimped to a spoke at the opposite end of my valve. For most bicycle riders this would not ever be a problem as their fun rider capabilities rarely allow them to see speeds of over 30 kph, but for the rest of us who are ?real? cyclists , well balanced wheels are not just marketing hype. <?:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />Pictures can follow on request.[/quote'] Ah, but Mr CarrionBoy, perhaps you missed a point or two. We really need a FAQ on this site, I'm now repeating something I explained long ago and it keeps on coming up. I'm in a permanent state of deja-vu. I said (or I hope I communicated it), that balancing a wheel before putting on the tyres and tubes is a futile exercise. You jut confirmed that as well. I also challenged whassisname to explain to us what an unbalanced wheel on a bicycle feels like but he chose not to answer. You just stepped into the trap that everyone else does and described the sensation of an unbalanced wheel as a "vibration", a sensation you no doubt associate with an unblanced wheel in a car where indeed, either the steering or the seat of your pants vibrate. Personally I prefer the latter, but that's neither here nor there. What it actually feels like on a lightweight unsuspended vehicle (and a suspended MTB is essentially an unsuspended vehicle if you consider the ration of the weight fo the wheel vs the weight of the bike), is not a vibration but a fore-aft pulsation. Pulsation because of the low frequency and fore-aft because the little bit of imbalance and low speed is not enough to compress the tyre and make the rig bounce up and down. Try it - put a rubber superball weighing 80grams in one of your MTB tyres and you'll definitely see that it is a) not a vibration and b) not up and down, but fore and aft. Tyres with super long stems, pimped wheels with skull and cross-bone valvecaps, golf balls inside tyres and other anomolies do produce that sensation and as you pointed out, a little fly-fishing weight does the trick. However, it is present in only the extreme scenario, it doesn't present as people think it does (vibration is cause by other things, not imbalance) and, it is just not an issue in 99.99% of cases. This notion of dynamically "pre-balancing" your wheels with thicker spokes is hocus pokus. As I said, if you regularly adjust hub bearings the right way, you'll be so frustrated with the relatively little imbalance of bike wheels that you'd wish they were worse so you can adjust the hubs quicker. Link to comment Share on other sites More sharing options...
Windbreaker Posted January 8, 2008 Share ... I also challenged whassisname to explain to us what an unbalanced wheel on a bicycle feels like but he chose not to answer. ... That's cause it's easier to play the man rather than the ball ...Windbreaker2008-01-08 10:31:41 Link to comment Share on other sites More sharing options...
Guest Big H Posted January 8, 2008 Share Baie geluk met jou verjaarsdag Windbreaker!!!!!!!and Mr Boredom real wheels have cartidge or ceramic bearings. Link to comment Share on other sites More sharing options...
Guest Big H Posted January 8, 2008 Share ... I also challenged whassisname to explain to us what an unbalanced wheel on a bicycle feels like but he chose not to answer. ... That's cause it's easier to play the man rather than the ball ... I had a chat with whassisname and he said that he does not have that problem as he is a flyfisher and have leetle weights on all his spokes making his wheels perfectly balanced...... this however makes the bike frightfully heavy!!!!! Link to comment Share on other sites More sharing options...
Guest Big H Posted January 8, 2008 Share Baie geluk met jou verjaarsdag Windbreaker!!!!!!!and Mr Boredom real wheels have cartidge or ceramic bearings. My goodness this is going to be intersting..... another seven page reply on the virtues of ceramic and cartridge bearings!!!!!!!! teee heeee!!!!!! Link to comment Share on other sites More sharing options...
Edition 507 Posted January 9, 2008 Share Ah, Mr JouHaan BoringMan (hey I didn?t start this, but lets see how creative we can get).<?:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /> I agree that it is a futile exercise balancing a wheel before putting on tubbies, valve extensions and pimped valve caps, but I disagree with your statements ?balancing wheels on a bicycle is hocus pocus? and ?On slower vehicles like bicycles, wheelbarrows and pizza cutters, there is no need to balance a wheel?. You also seem to contradict yourself with your reference to fly fishing weights and constant cone and hub bearing adjustments in later posts. Your assumption as to the type of vibration occurring on my wheels was also rather presumptuous. My wheels were balanced on a bike stand and the vibration was not due to maladjusted cones, simply because my hubs have cartridge bearings. These seem to be something you are not familiar with as your reference to cones and fiddling with hub bearings alludes to this fact. Also, whether the vibration is fore and aft or up and down, it still needs balancing, and whether you use motor bike wheel balancing lead, fly fishing equipment or a simple cycle computer magnet to achieve this, is irrelevant. Big H, you mention ceramic bearings, funny you should bring this up as I have retro-fitted Ceramicspeed ceramic bearings to my freewheel and hubs, along with a FSA Ceramic BB and Enduro ceramic jockey wheel bearings (pictures can follow on request). Now, without trying to start another hot debate, there is a proven and measurable benefit by going ceramic, however, just like riding a super light R60,000 bike while being a good few kilos overweight, I doubt I will ever notice it. Link to comment Share on other sites More sharing options...
SwissVan Posted January 9, 2008 Share Balancing bicycle wheels? Why would anyone want to do that?? Must be bored???Cause otherwise it would be a waste of time????What are the side effects of an "out of balance" bicycle wheel while being ridden????? How many pro race bikes (or mtb bikes while we're there...) do you see with "balanced wheels" Surely if there was any negative effect due to out of balance wheels these guys who spend most of their day riding would be pedantic about it?????? <?:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /> Link to comment Share on other sites More sharing options...
Guest Big H Posted January 9, 2008 Share Swiss, neither can I understand why you should balance something mundane as bicycle wheels. This whole post erupted as I expected it would after I quoted from and "innocent" article I read in a magazine. I have never really worried about this. I however knew that an essay of several pages on the topic would follow where the abilities of everybody including myself and the established builders and designers would be questioned.......... as the records show I was right, as always, in my assumption. I have started a programme on site of balancing wheelbarrow wheels, our steel wheel rollers, graders, excavator and bulldozers(the tracks are extremely difficult to balance properly) and front end loaders. Facinating!!!!!!! Teeee heeee!!!!!!Big H2008-01-09 21:59:12 Link to comment Share on other sites More sharing options...
Johan Bornman Posted January 9, 2008 Share Ah' date=' Mr JouHaan BoringMan (hey I didn?t start this, but lets see how creative we can get).<?:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /> Snip snip snip... You also seem to contradict yourself with your reference to fly fishing weights and constant cone and hub bearing adjustments in later posts. Your assumption as to the type of vibration occurring on my wheels was also rather presumptuous. My wheels were balanced on a bike stand and the vibration was not due to maladjusted cones, simply because my hubs have cartridge bearings. These seem to be something you are not familiar with as your reference to cones and fiddling with hub bearings alludes to this fact. [/quote'] You read me wrong. I had hoped not to have to go into a lengthy explanation since home mechanics should know this but here goes....When you adjust your hub bearings (this has now nothing to do with wheel balancing), the last step of the process is to put the wheel in the bike, clamp it and see if the QR's compression isn't exceeding minimum bearing play. You do this by checking that the wheel still stops at the heaviest point each time. Remember, the QR compresses the bearings and if they were right on the bench, they're almost certainly too tight on the bike. If the wheel was perfectly balanced, you can't check the bearing this way. However, most wheels aren't balanced and you can. Also' date=' whether the vibration is fore and aft or up and down, it still needs balancing, and whether you use motor bike wheel balancing lead, fly fishing equipment or a simple cycle computer magnet to achieve this, is irrelevant. [/quote'] My point lies in the semantics. If you experience a vibration, it is not a wheel balancing problem but something else. If you experience a fore-aft pulse, then you can start to fiddle with wheel balancing, but as I say, this is very, very rare. A bicycle wheel is large (2m plus circumference) and it turns slowly, therefore an imbalance doesn't vibrate as it does in a car. Link to comment Share on other sites More sharing options...
Tumbleweed Posted January 9, 2008 Share this won't add anything to the debate, and i'm not going to be nasty to anyone, but the wrencher at my lbs once laced a set of wheels by using black spokes for the drive spokes and silver for the rest. looked really odd Link to comment Share on other sites More sharing options...
Windbreaker Posted January 9, 2008 Share CarbonBoy, I did a Google on Bicycle wheel balancing and found nothing which overtly supports your experience - that balancing a bicycle wheel the way you describe has a profound impact. Here is the best info that I have found. I haven't been able to digest it all yet - work time. If I'm not mistaken Jobst Brandt is a world leading expert on bicycle wheels. Or at least he makes his money from it. If there were significant benefits associated with bicycle wheel balancing then I guess that he would be at the forefront of perfecting the "art". http://yarchive.net/bike/wheel_balancing.html Link to comment Share on other sites More sharing options...
Guest Big H Posted January 9, 2008 Share this won't add anything to the debate' date=' and i'm not going to be nasty to anyone, but the wrencher at my lbs once laced a set of wheels by using black spokes for the drive spokes and silver for the rest. looked really odd[/quote'] Was this a case of "undynamic imbalance" .......mmmmmmmm!!!!!!!????? Link to comment Share on other sites More sharing options...
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