Smoother Posted October 30, 2016 Share Posted October 30, 2016 Title says it all. New unit. Tire was about 12psi out of box. Pumped it up to 65 psi as per tire max. Rode indoors for 20 minutes. Took outdoors a few days later, tire felt squishy. Gauge read 45psi. so, is it normal for a brand new tire to lose about a third of its pressure in two days? is there a common problem with inner tubes or valves on these units? Link to comment Share on other sites More sharing options...
Cloud Posted October 30, 2016 Share Posted October 30, 2016 This is a constant problem with mine too. However it happens after while. Here is the thing. The higher psi you pump it to the more you will be losing over time. Also, when you connected the gauge both when you pumped to 65 and when you check it later, did some air come out? Even if a little air comes out when you disconnect the pump it can lower the pressure a lot and you woukd be thinking its still high. So maybe its not so bad. No, two days is too fast. You may need to replace the tube. It should hold for at least a week. so the first thing you do is pump it to about 50, dont pump to 65. How much do you weigh? Try to disconnect the pump quickly so air doesnt come out when disconnecting, Try it, if you are still losing a lot of air, you will need to get a replacement tube and replace it. Its not worth patching the tube as you have to do a lot of work to get it out, so doesnt make sense to do a cheap patch after spending time to get the motor out. I have to do the same on mine as mine lowers after 3 days now. Link to comment Share on other sites More sharing options...
Smoother Posted October 30, 2016 Author Share Posted October 30, 2016 Yes I'm aware that the smaller the volume of are in a tire the more , as a percentage leaks out while trying to remove the pump. I did try to do it as quickly as possible and no, I don't believe I lost it removing the pump hose it it wasn't squishy immediately afterwards, but it was 2 days later oh well a new tube it is. thanks for confirming that. Link to comment Share on other sites More sharing options...
Greg Spalding Posted October 30, 2016 Share Posted October 30, 2016 my ninebot miniPRO loses 20 psi every week when it sits around but holds pressure well during a 12-mile ride Link to comment Share on other sites More sharing options...
Cloud Posted October 30, 2016 Share Posted October 30, 2016 1 hour ago, Smoother said: Yes I'm aware that the smaller the volume of are in a tire the more , as a percentage leaks out while trying to remove the pump. I did try to do it as quickly as possible and no, I don't believe I lost it removing the pump hose it it wasn't squishy immediately afterwards, but it was 2 days later oh well a new tube it is. thanks for confirming that. I am not saying its going to be squishy after removing the pump, but it may lose 5-7 psi instantly right there if the air comes out even for a split second. I am just saying it will affect your count. Just pumo it again to about 50-55 psi and see what happens in a couple of days before going thru the trouble of changing the tube. Now, where are you going to get the tube? It is i portant to get the tube not onky with the curved/ angled/ bent valve but also the valve has to be bent in the plane of the tube ( not perpendicular to it). Most tubes with bent valves that are for sale are for the bikes and the valve sticks out perpendicular to the plane of the tube - this will not fit. So make sure you see the picture of the tube before buying. There will be nothing in the description to tell you which way it curves. Link to comment Share on other sites More sharing options...
Greg Spalding Posted October 30, 2016 Share Posted October 30, 2016 4 minutes ago, Cloud said: I am not saying its going to be squishy after removing the pump, but it may lose 5-7 psi instantly right there if the air comes out even for a split second. I am just saying it will affect your count. Just pumo it again to about 50-55 psi and see what happens in a couple of days before going thru the trouble of changing the tube. The 10 1/2 inch tires on the miniPRO are so small that you will remove at least 10 psi just connecting it to the pump. There is no reason to ever check your pressure on that unit unless you're planning on adding air. Link to comment Share on other sites More sharing options...
Smoother Posted November 1, 2016 Author Share Posted November 1, 2016 I'm about 85kg (187lbs) if you divide 187lbs ( my weight) by 65psi ( max tire pressure stated on sidewall) you get 2.88 inches. So if I'm doing my physics right (and I'm no rocket surgeon) that means at 65 psi 2.88 square inches of tire have to be in contact with the road to support my weight. If I reduce the pressure to 50 psi (187/50) I need 3.74 square inches of contact. on a tiny, thin, 14" tire, that's a big ask; as in running around with a big flat spot on the bottom. If I was on a bicycle the load would be shared by two tires; not such a big ask, per tire. So im thinking that I should be pumping it up 5 psi over max to allow for air loss on disconnect, check it with a gauge ( which will result in a little more air loss) and hopefully It'll be rightish. No? Am I missing something here? I know we don't usually pump road vehicle tires up to their max, but I do know that we should pump them up more if they are to carry an extra load; a load that will force them, at normal pressure, to squash down in order to obtain the correct pressure to contact patch ratio. I consider a mildly fat full grown male on one tire from a child's bike, to be a an "extra load" . I've watched quite a few vids of people jumping off kerbs, etc, some detailed and in slow motion. You can really see the tire deflect under the extra load created by the combined weight of rider and machine accelerated vertically by gravity. I would not like to do that on a squishy tire (pop!) ks 14 is in transit right now. Hasn't been pumped up or ridden since Saturday. I'll measure the pressure when I next see it and see if it comes close to the 65psi I put in the other day ( - leakage when Hose was removed). Good advice about valve orientation, @Cloud thanks. I might have missed that nuance. Link to comment Share on other sites More sharing options...
Cloud Posted November 1, 2016 Share Posted November 1, 2016 4 hours ago, Smoother said: I'm about 85kg (187lbs) if you divide 187lbs ( my weight) by 65psi ( max tire pressure stated on sidewall) you get 2.88 inches. So if I'm doing my physics right (and I'm no rocket surgeon) that means at 65 psi 2.88 square inches of tire have to be in contact with the road to support my weight. If I reduce the pressure to 50 psi (187/50) I need 3.74 square inches of contact. on a tiny, thin, 14" tire, that's a big ask; as in running around with a big flat spot on the bottom. If I was on a bicycle the load would be shared by two tires; not such a big ask, per tire. So im thinking that I should be pumping it up 5 psi over max to allow for air loss on disconnect, check it with a gauge ( which will result in a little more air loss) and hopefully It'll be rightish. No? Am I missing something here? I know we don't usually pump road vehicle tires up to their max, but I do know that we should pump them up more if they are to carry an extra load; a load that will force them, at normal pressure, to squash down in order to obtain the correct pressure to contact patch ratio. I consider a mildly fat full grown male on one tire from a child's bike, to be a an "extra load" . I've watched quite a few vids of people jumping off kerbs, etc, some detailed and in slow motion. You can really see the tire deflect under the extra load created by the combined weight of rider and machine accelerated vertically by gravity. I would not like to do that on a squishy tire (pop!) ks 14 is in transit right now. Hasn't been pumped up or ridden since Saturday. I'll measure the pressure when I next see it and see if it comes close to the 65psi I put in the other day ( - leakage when Hose was removed). Good advice about valve orientation, @Cloud thanks. I might have missed that nuance. Whether your physics are right or wrong, you are going about it the wrong way. Dont concern yourself with the area of contact. Instead use emperical data from other riders. I am 100kg and ive ridden about 6-7000 km on ks14. I can tell you that with 85kg, 50-55 should be high enough pressure. Just see how it feels to ride. If you have a good control of the wheel at this pressure and it doesnt sway from side to side, then its the right pressure for you. You can pump to a few more psi to compensate for the loss when you are connecting a gauge, if you want. i dont recommend jumping off curbs at any pressure for a number of reasons. I am not sure if this is what you are looking to do. yes the valve orientation thing is very real. I know because i made the same mistake and bought the wrong ones, twice. later on, i can look up where i got the correct ones, and can post the link if you want. Link to comment Share on other sites More sharing options...
Smoother Posted November 1, 2016 Author Share Posted November 1, 2016 Ok I'll set my target at 55 and see how she rolls. 6-7000km ! Jeez. You really don't like paying bus fare ? link to tube supplier might be nice, might even be worth the postage. Things over here always seem to be 50% higher than there, EUC's excluded. Link to comment Share on other sites More sharing options...
Cloud Posted November 2, 2016 Share Posted November 2, 2016 4 hours ago, Smoother said: Ok I'll set my target at 55 and see how she rolls. 6-7000km ! Jeez. You really don't like paying bus fare ? link to tube supplier might be nice, might even be worth the postage. Things over here always seem to be 50% higher than there, EUC's excluded. Yes , i basically dont walk anymore, except in the office. here is the link to the amazon page https://www.amazon.com/gp/product/B013SHOZ52/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1 it says currently unavailable, but maybe you can find similar products. Note the valve orientation in the photo, this is the corretc orientation also, you can contact one of our distributors - @Jason McNeil - he should have this accessory in stock at his website Link to comment Share on other sites More sharing options...
YaocH Posted November 2, 2016 Share Posted November 2, 2016 19 hours ago, Cloud said: I am 100kg and ive ridden about 6-7000 km on ks14 Have you noticed a significant loss in capacity of the battery after having done so much mileage? Any specific part of the unicycle failed or required replacement? Link to comment Share on other sites More sharing options...
Cloud Posted November 3, 2016 Share Posted November 3, 2016 20 hours ago, YaocH said: Have you noticed a significant loss in capacity of the battery after having done so much mileage? Any specific part of the unicycle failed or required replacement? The mileage was distributed mainly over 2 ks14c units. There is a lot that hapoened over this distance, i could probably write a book on all the replacements i had to make. Some were related to the high mikeage and some were not. Some were due to my own mistake. long story short, yes there was some decrease in battery performance. What will likely need replacement due to the high mileage is the main axle, especiialy fir heavier riders. The pedal posts will need to be tightened up several times. Tube and tire of course. Other parts could potentially hold up over distance. Battery performance will decrease Link to comment Share on other sites More sharing options...
Hunka Hunka Burning Love Posted November 3, 2016 Share Posted November 3, 2016 Do you think using some Loctite Blue on the pedal bolts might prevent them from working loose? http://www.boltscience.com/pages/vibloose.htm Link to comment Share on other sites More sharing options...
who_the Posted November 3, 2016 Share Posted November 3, 2016 2 hours ago, Cloud said: What will likely need replacement due to the high mileage is the main axle, especiialy fir heavier riders. The pedal posts will need to be tightened up several times. Tube and tire of course. Other parts could potentially hold up over distance. Battery performance will decrease Awesome guidance for scheduled maintenance. I'm (only) around 1,600km after 6 months on my KS-14C and haven't had to do any of this, so I consider myself fortunate. And I will prepare to do it sometime (soon) in the future. Link to comment Share on other sites More sharing options...
Smoother Posted November 3, 2016 Author Share Posted November 3, 2016 On 30 October 2016 at 10:32 PM, Greg Spalding said: my ninebot miniPRO loses 20 psi every week when it sits around but holds pressure well during a 12-mile ride I'm impressed that a miniPRO will go that far on a charge. When I owned Segways, they were hard pressed to go 12 miles. I didn't think of the miniPRO as a serious mileage machine. I'll think again. Link to comment Share on other sites More sharing options...
Greg Spalding Posted November 3, 2016 Share Posted November 3, 2016 18 minutes ago, Smoother said: I'm impressed that a miniPRO will go that far on a charge. When I owned Segways, they were hard pressed to go 12 miles. I didn't think of the miniPRO as a serious mileage machine. I'll think again. At 42 psi and with my almost 90 kg of "riding" weight... I more than pleased with that range I know they are made fun of around here, but as I've said before, the only reason why I found this forum and became interested in EUCs in the first place was because a friend... A very dear friend gave me a miniPRO as a birthday present. There is a Saturday morning market in the city, not far away where there are hundreds of people milling about, and several other outdoor activities in a 10 x 10 block area. That is just the perfect kind of environment to enjoy on the miniPRO because it does a better job meandering through such a crowd because of the ability to stop and turn and weight without having to get on and off like one would on an EUC. Technology is a wonderful thing and becoming more amazing on a daily basis. I'm happy I found this place and all the wonderful people here... And I await 34 more hours to elapse until my MSuper and MCM 4 arrive. Link to comment Share on other sites More sharing options...
Smoother Posted November 3, 2016 Author Share Posted November 3, 2016 "A very dear friend gave me a miniPRO as a birthday present." does your friend need any more friends? I can make room for one more ? But seriously, your point about stopping, waiting, etc around people, is well made. I think my next wheel might just have to be two wheels. MiniPRO's aren't expensive, and with the optional handle, do most things a giant, heavy Segway can do, small tires not withstanding. Link to comment Share on other sites More sharing options...
Cloud Posted November 3, 2016 Share Posted November 3, 2016 7 hours ago, who_the said: Awesome guidance for scheduled maintenance. I'm (only) around 1,600km after 6 months on my KS-14C and haven't had to do any of this, so I consider myself fortunate. And I will prepare to do it sometime (soon) in the future. Look up this thread, i posted a much longer list of suggested maintenance of the wheel which is very much applicable to ks14c Link to comment Share on other sites More sharing options...
Smoother Posted November 19, 2016 Author Share Posted November 19, 2016 UPDATE. Pressure holding steady. Must have escaped when I removed the pump hose. Factory inner tube, all good. End of message. Link to comment Share on other sites More sharing options...
Greg Spalding Posted November 19, 2016 Share Posted November 19, 2016 12 minutes ago, Smoother said: UPDATE. Pressure holding steady. Must have escaped when I removed the pump hose. Factory inner tube, all good. End of message. glad thanks for the update Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.