MCM5 tire issue

[Xthrax]

I had a big crash today. The unit not me. I was able to step off in time. The tire ran out of pressure while I was almost at full speed. This happened to me once before a few months ago. 2 days ago I replaced the innertube and it kept a stable 40 PSI. Now the tube is shot again and I need to disassemble the whole thing and get a new replacement.

I dont understand why this is happening. Do I need to get a new tire and tube?

[Tawpie]

I'd certainly do a close inspection of the tire and tube, same as you would do with a bike tire... there might be something sharp in the tire body that eventually pokes a hole in your tube. Tubes can be repaired if you do a good job. Also verify that nothing is wrong with the valve. The standard "inflate the tube and dunk it in soapy water, watch for bubbles" procedure is very effective to find leaks in tubes. Tires, you pretty much have to carefully feel the inside for projections and inspect the outside for signs of things that may have poked into the tire.

It won't save you forever, but I run an anti-puncture fluid called Ride-On in my tire to try to heal small punctures on the fly. It's similar stuff to Slime, and there's lots of other cousins. Might be worth a try. But if my tire looses pressure for no good reason, it gets inspected carefully.

Excellent that you weren't hurt! ATGATT.

Edited March 15, 2021 by Tawpie

[alcatraz]

When you take the tube off, make a note of its position in the tire and on the rim. Then inflate it and locate the leak, and check rim/tire in that location. Maybe you need to grind some sharp edges or improve your installation skills, or get some remaining sharp fibers out.

[Xthrax]

I think I will just try replacing the tire and the inner tube. I am dont patching and slimeing. To me its a waste of time. I have had slime (anit-puncture) fluid fail on me. Plus they are not that expensive. If it fails again, I am getting another wheel.

[Scottie888]

Unless its bald or there's a major cut/gouge, likely you don't need a new tire. However its likely you need to either patch the leak or replace the inner tube. Surprise of all surprises, EUC tires are very similar to type & quality of cheap bike tires which fwiw, are also very prone to flats. Except its much easier to do a tube repair/replacement on the bike for obvious reasons. Most serious cyclists carry a patch kit &or spare tube + tools with them as EDC.

Slime &or other such aren't dummy proof. Its just something extra so we can sleep better or for that 1in10 chance where it really does save your ass from carry 40-60lbs worth of boat anchor home.

Since you're gonna do a replacement, might I suggest you look into offroad or better yet, a dual sport knobby for the type of riding you're doing. 

[Xthrax]

13 minutes ago, Scottie888 said:

Since you're gonna do a replacement, might I suggest you look into offroad or better yet, a dual sport knobby for the type of riding you're doing. 

I dont do a lot of offroading but the roads where I live are not in good shape so that might be a good idea anyway thanks for the tip.

[Xthrax]

This is something I need. Didn't even think about till now. I'll make sure to have a small hand/foot pump with me at all times.

https://www.amazon.com/FOBO-Pressure-Monitoring-Systems-Silver/dp/B07Q21RNNB/?tag=td-motorcycle-tpms-pcr-20&th=1&psc=1

[Xthrax]

New and improved. Now I just need to wait for my tire pressure sensor to arrive and I should not be caught off guard like before.

[Scottie888]

36 minutes ago, Xthrax said:

New and improved. Now I just need to wait for my tire pressure sensor to arrive and I should not be caught off guard like before.

Is that for the Mten3?? Looks too narrow to be 3"

[Xthrax]

MCM5 v1 but now better wheel for low maintenance roads

[Xthrax]

Ok it deflated again and I have not even mounted it. I put a new tire, new tube, and used slime fluid. It still deflates.

Pretty much ready to junk this guy now.  I still want an electric unicycle but I think I got sold a lemon.

[yuweng]

Dirt bike tyre is a completely new beast, i've busted 4 tubes continuously until i watch these & learned how to use the proper tools & not to pinch the tube while installing it back 

[.....]

10 hours ago, Xthrax said:

Ok it deflated again and I have not even mounted it. I put a new tire, new tube, and used slime fluid. It still deflates.

Pretty much ready to junk this guy now.  I still want an electric unicycle but I think I got sold a lemon.

Probably cant fault the hardware. It COULD be a tube or tire or rim issue, but most of the time its installer error/foreign material/pinch. I've pinched many in my day. You need to check the rim for burrs. Check the tire for the same. Look to see if you notice the tube is cut/pinch  or like a hole. I hate hearing this, but I've been down that road before. After you air up the next try with a new tube, let it sit without putting the rim back in the euc, and spray the rim bead and valve with dish soap/water. If you see bubbles after 10 minutes, you have another leak. Bubbles at first, may be the air between the tube and tire, so ignore that.

Thats a badass looking tire you got there! I'd get 2 more tubes and keep trying. Unfotunately, you would run into similar issues on antoher euc, if the installer is the problem. Its a good practice to inflate a tube a little then air it out. Then a little more. and so on. You need to insure it hasnt twisted and the valve lines up. Also remember to check the core. You wouldnt want to mistake it and ruin a tube over a core being loose. I personally dont use slime as it makes a mess, but thats probably of nill consequence.

 

Edited March 18, 2021 by ShanesPlanet

[Xthrax]

On 3/18/2021 at 4:29 AM, ShanesPlanet said:

Thats a badass looking tire you got there! I'd get 2 more tubes and keep trying. Unfotunately, you would run into similar issues on antoher euc, if the installer is the problem. Its a good practice to inflate a tube a little then air it out. Then a little more. and so on. You need to insure it hasnt twisted and the valve lines up. Also remember to check the core. You wouldnt want to mistake it and ruin a tube over a core being loose. I personally dont use slime as it makes a mess, but thats probably of nill consequence.

 

Thanks for the words of encouragement. I think I was just really frustrated at how much trouble I have had with this wheel. I went to the store got two more tubes and, tested one and replaced the tube. The previous just broke for no reason. manufacturing imperfection. The new tire is holding now. I am not going to ride it until I get the tire pressure sensors next week.

[.....]

Tire pressure sensor? Are you referring to a simple tire gauge? YOu can always air it up and feel it by hand. Surely you've done that as a kid with bicycles. Firm but not too firm. You know, like a young womans.....   doh. I mean, like a basketball. Glad to hear you got it a little further. I totally get how frustrating tubes can be. I have ruined my fair share and purchased many that were unfit to be sold to begin with. After MANY MANY years, i finally refuse to try replace tires without proper tire irons. OMFG th money I've wasted in damaged tubes and aggravation, while trying to save $30 on proper tools. Always buy at least TWO tubes, anytime you have less than two and get a flat. Wasting $10 on a tube you never use, is much better than ruining the only one you got and wasting a single sunny day of riding over it!

Edited March 20, 2021 by ShanesPlanet

[Xthrax]

1 hour ago, ShanesPlanet said:

Tire pressure sensor? Are you referring to a simple tire gauge? YOu can always air it up and feel it by hand. Surely you've done that as a kid with bicycles. Firm but not too firm. You know, like a young womans.....   doh. I mean, like a basketball. Glad to hear you got it a little further. I totally get how frustrating tubes can be. I have ruined my fair share and purchased many that were unfit to be sold to begin with. After MANY MANY years, i finally refuse to try replace tires without proper tire irons. OMFG th money I've wasted in damaged tubes and aggravation, while trying to save $30 on proper tools. Always buy at least TWO tubes, anytime you have less than two and get a flat. Wasting $10 on a tube you never use, is much better than ruining the only one you got and wasting a single sunny day of riding over it!

I ordered these. https://www.amazon.com/FOBO-Pressure-Monitoring-Systems-Silver/dp/B07Q21RNNB/?tag=td-motorcycle-tpms-pcr-20&th=1&psc=1

In 2 cases I had my tire be prefect when I start a ride and go flat suddenly without running anything over. Its almost caused my serious injury, again. So I will use one of those sensor to get a warning if tire is going flat fast.

[alcatraz]

Sure you're not pinch flatting? When bottoming out even for an instant you pinch the tube between tire and rim.

Some tubes can't take being pinched even once. Ride a low enough pressure and you can pinch flat on a flat road.

Try riding a higher pressure. Some pressure gauges are way off. Just because someone says X psi doesn't mean you should ignore common sense and trust your gauges.

Personally I don't trust my gauges enough to compare values. I just remember that pump Y needs to show value Z psi. If I switch pumps I need to figure out the value that meter shows for the pressure I like.

Pinch flats look like snake bites in an underwater leak test, and they're always on the side of the tube. They're easy to spot that way.

Edited March 22, 2021 by alcatraz

[Xthrax]

On 3/22/2021 at 7:05 AM, alcatraz said:

Sure you're not pinch flatting? When bottoming out even for an instant you pinch the tube between tire and rim.

Some tubes can't take being pinched even once. Ride a low enough pressure and you can pinch flat on a flat road.

Try riding a higher pressure. Some pressure gauges are way off. Just because someone says X psi doesn't mean you should ignore common sense and trust your gauges.

Personally I don't trust my gauges enough to compare values. I just remember that pump Y needs to show value Z psi. If I switch pumps I need to figure out the value that meter shows for the pressure I like.

Pinch flats look like snake bites in an underwater leak test, and they're always on the side of the tube. They're easy to spot that way.

I keep my tire inflated at 40psi, and I feel it with my hand. I dont think that was the case. I dont go over many bumps, the biggest issues on the imperfect roads I ride on is warped cement. You ride on what you think is a flat surface until one side of the road has slumped over time and you have to rebalance and find the flat part.

The last flat I got, it deflated before I was even able to ride it.

[Camenbert]

These BTWIN tyres are made for kid bicycle, sold $15 by decathlon.
I cant find the datasheet, but on Schwalbe for this rim size, the max load is 60 KG (or 40 KG is the wheel is 20) !

I guess just this explain your random issues.

14" bicycle tire = 10" motocross tire = 254mm rim
If you want all terrain tire, I would look for a 10" motocross tire and stay away of the kids one !!

What year is your MCM5 ?
The smallest size i see is 2.5", OK for latest 2020 V2 enlarged model but not the V1 "narrow" body-shell (database : https://www.pneus.fr/pneus/moto/motocross/10/202?rows=50 - maybe the Chinese have other sizes)

Good news, these 2.5" are "33J" meaning good for 115 KG/100KpH (might be a nightmare to mount)

 

[Xthrax]

1 hour ago, Camenbert said:

These BTWIN tyres are made for kid bicycle, sold $15 by decathlon.
I cant find the datasheet, but on Schwalbe for this rim size, the max load is 60 KG (or 40 KG is the wheel is 20) !

I guess just this explain your random issues.

14" bicycle tire = 10" motocross tire = 254mm rim
If you want all terrain tire, I would look for a 10" motocross tire and stay away of the kids one !!

What year is your MCM5 ?
The smallest size i see is 2.5", OK for latest 2020 V2 enlarged model but not the V1 "narrow" body-shell (database : https://www.pneus.fr/pneus/moto/motocross/10/202?rows=50 - maybe the Chinese have other sizes)

Good news, these 2.5" are "33J" meaning good for 115 KG/100KpH (might be a nightmare to mount)

 

It probably is made for kids but I also had the same issues with the original gotway tire. I only switched because I was fed-up with burning through inner tubes and wanted eliminate the tire as the potential problem.

No idea how hold the MCM5 but I think it might be 1st generation because I have seen two newer  versions of the board I use to have.

I have not enjoyed mounting these wheels. I have had to take them to car/motorcycle shops and paid them to mount it with special tools. And evetime I have to pull the wheel out the overall quality of the wheel goes down. Screws dont hold as tight when you have had to crew them into place many times.

[alcatraz]

Is the tube valve mounted so it exits against the travel direction? That way you protect the valve. Also try using a valve cap.

If it isn't a puncture it can only be the valve. 

[Ben Kim]

the tube went flat on my mcm5v2 a few weeks ago, not from any road hazards but because the valve stem detached from the tube. Honestly I think it was long coming because this new tube is holding a solid 40 psi, whereas my old tube lost air around 1-2 psi per week. 

[Xthrax]

I invested in some tire pressure sensors because I had a point where it went flat while in motion. I had to step off and let it crash.

So now I am constantly checking the pressure and the temperature every stop

[Camenbert]

On 4/24/2021 at 5:29 PM, Xthrax said:

I invested in some tire pressure sensors ...

Interesting, how does this work, you had to convert to tubeless first, right ?
Is this tire pressure sensor part of the tubeless valve ? How does it fit on MCM5 rim ?

When my tube is crap i would do the same - however the CST 1813 have no mention of tubeless, will it work...

Edited April 29, 2021 by Camenbert

[Xthrax]

6 hours ago, Camenbert said:

Interesting, how does this work, you had to convert to tubeless first, right ?
Is this tire pressure sensor part of the tubeless valve ? How does it fit on MCM5 rim ?

When my tube is crap i would do the same - however the CST 1813 have no mention of tubeless, will it work...

I use a tube, the TPS actually fits on as a cap to the tube. It small enough to not scrape the inside of the MCM5 hull. So you fit is on as a cap and then link your phone via the app to the sensor. You can set an audible warning when the pressure is low. Its a little on the expensive side but less expensive then crashing from a fast deflate while in motion then a emergency room visit.