MCM5 v2 3-inch tire?

[litewave]

Note: I started to create a new topic but decided to bump this thread since it is so full of great contributions.

I have been loving my eWheels-upgraded MCM5v2 for nearly four months. It's a homely-looking barbie-esque suitcase that only a dorky alien could love, but man, it is one zippy little wheel. I bought this wheel as well as a Bridgestone Hoop 2.75" tire at the same time based on the @Denny Paul@Surfling@EMAand @houseofjob awesome hacks.

I have finally broken enough plastic on the shell (inner flanges and cooling fan, mostly) and no longer have any qualms about cutting into it and installing the larger tire. I'm hesitating, however, because I simply love the 14" as-is. I know my local area very well and most all the roads and paved trails are smooth as silk, and the 14" is just so nimble. Is the larger tire really enough of an upgrade to make me never look back, or do I need two of these?

 

Edited May 6, 2022 by litewave

[Denny Paul]

My opinion is that the 3” tire is a straight-up upgrade. It’s not necessary to appreciate the Mcm5, but it’s an improvement on an already great wheel.

Enough of one? Really subjective. Only you could be the judge of that for yourself. If your roads are really that perfect around you, maybe it doesn’t make much of a difference.

But if you have the time, why not? Even if I had perfect roads, the fatter tire is something I like. I still wouldn’t change it back.

[EMA]

14 hours ago, litewave said:

I have finally broken enough plastic on the shell (inner flanges and cooling fan, mostly) and no longer have any qualms about cutting into it and installing the larger tire. I'm hesitating, however, because I simply love the 14" as-is. I know my local area very well and most all the roads and paved trails are smooth as silk, and the 14" is just so nimble. Is the larger tire really enough of an upgrade to make me never look back, or do I need two of these?

the 3'' tire upgrade change the geometry a bit in a way that you can like or not:

• it become higher from the ground, impossible to scrape pedals, even offroading
• became the most agile wheel ever to me (after mten3 of course), but you need to be more precise at speed
• could wobble, 2.5'' never do it
• 2.5'' carve a bit easier, 3'' stay more up at speed
• it's way more comfortable for sure, but if you ride smooth surface...
   

original 2.5'' wheel reminds me a slower smaller tesla
modded with 3'' tire seems a godlike mten3

Edited May 6, 2022 by EMA

[JMartin]

With all this tire changing and no one converted to tubeless? I've looked at the rim profile on my MCM5v2, and realize drilling the stem hole will be a challenge. (It was a breeze on my son's mten3.) My first flat and I'll try to convert.

Jay

[Surfling]

The MCM5 valve hole is in groove. It could be challenging making the tubeless valve air-tight in a curved area. Good luck and post any results pls.

[Camenbert]

I have my second flat, once a year, and I'm tempted by a tubeless conversion. Only the outside of the valve hole need to be flat so it's air-tight. Also increasing the hole from 8.3mm to 11.3mm would give the freedom to change the angle of the valve in order to use one of these :

Unfortunately I am not a machinist and I dont trust my skill with a drill to do it. But maybe someone would try ?

Otherwise the Bridgestone 2.75 require of course mods on a MCM5 V1, but what about V2 shell ? I otherwise like the Michelin S83 3.0-10, it look rather narrow but tall. And still tubeless.

[JMartin]

I am thinking the stem will need to be angled. Something like this:  

[JMartin]

I spoke with a machinist friend about enlarging the stem hole in the V-shaped MCM5v2 so as to go tubeless. He said one could do it from the outside with a Dremel, but you run a high risk of making the hole egg-shaped. It would be better if we could get a straight shot at it with a drill from the backside.

If you have a good set of drill bits it would be good to increase the hole diameter 1/32" at a time. Otherwise go 1/16". Drill should be medium speed, around 300 rpm. Use gentle pressure and some oil.

When I did my son's wheel I had someone else running a shop-vac to catch the metal filings which kept the mess to a minimum.

Jay

 

[Camenbert]

17 hours ago, JMartin said:

I am thinking the stem will need to be angled. Something like this:  

Indeed this look better suited, I only could find straight and 90° ones so far. I already upgrade my MCM5 v2 from 2.125 to 2.5 last year, will wait a bit more to change for a proper tubeless one.

13 hours ago, JMartin said:

I spoke with a machinist friend about enlarging the stem hole in the V-shaped MCM5v2 so as to go tubeless. He said one could do it from the outside with a Dremel, but you run a high risk of making the hole egg-shaped. It would be better if we could get a straight shot at it with a drill from the backside.

If you have a good set of drill bits it would be good to increase the hole diameter 1/32" at a time. Otherwise go 1/16". Drill should be medium speed, around 300 rpm. Use gentle pressure and some oil.

When I did my son's wheel I had someone else running a shop-vac to catch the metal filings which kept the mess to a minimum.

Jay

 

The idea behind increasing the hole size is to change the angle of the stem in order to use a straight one, I'm not sure it's require with the one you found (may you post a link? found as BikeMaster Chrome Valve Stems 45° 12114).

I mounted a no-name 3.00-10inch Honda scooter tube that was 3 time heavier than original one and it was holding much better the air (just adding air every few months instead of weeks if not days), but the 90° side-way stem was touching the shell. I had to twist it as I inflate the tire so it wont.

I just order Michelin off-road reinforced tube, 2mm tick (Michelin CAI 155574 or in US Michelin 85074 Inner Tube 2.50/2.75-10 - TR-4), maybe that will work a bit longer...

 

Edited July 3, 2022 by Camenbert

[OneLeg]

I installed a Chao Yang tire on my MCM and as it is far more bouncy and soft the 2.15" tire way thicker now, like 2.7"  at 35 PSI... who knows what happens if I pump it to 42 PSI... You lose manouverability, have larger turning circles... the MCM was already great on 40-50km rides...

I don't see the value I got installing the chao yang tires on a 14" wheel like you do on a GT16....

I would stick the the original CST, harder but more nimble.

 

[JMartin]

On 7/3/2022 at 7:26 AM, Camenbert said:

...The idea behind increasing the hole size is to change the angle of the stem in order to use a straight one, I'm not sure it's require...

One has to increase the hole size for tubeless, typically to 13/32" or a little less. This is probably a better example where you can see the wide rubber base that fits in the enlarged hole. I used a TR412 on my son's MTEN3. But with the "V" rim on the MCM5 v2, I think we will need one with an angle.

Jay

 

[Camenbert]

I just repair my flat. So obviously oversize tube is a bad idea. This scooter/motorcycle tube was good rubber (and 1/4 the price of "euc tube" !!) but had a hole in the fold as 3.0/3.5-10 in a 2.5" tyre.

About going tubeless, when you see where is the hole, about where the tyre seat, I have doubt.
And if the stem fit, there is no guarantee you can go around installing a tick heavy tubeless tyre.

Here are some picture of the Michelin 2.5 reinforced tube for off road install. As it have a staight stem, you have to remove some aluminium from the black painted side disc, use the provided washer on the stem, maybe add one more, and use the extension as seen to be able to inflate.

Edited July 12, 2022 by Camenbert

[Camenbert]

[Camenbert]

It barely touch the inside shell, so a second washer or removing a bit more material (I could do more indeed) is require. I will just use a hammer to flatten the corner. 1mm is enough in my case.

To make the groove, I use a file then the biggest drills i had, pushing side-way. And yes the extension valve should be on the other side as it rotate forward.

I hope to never repair a flat again as this Michelin tube looks bullet proof.

Edited July 12, 2022 by Camenbert

[thendless]

I noticed this 3.2 inch tire on aliexpress: US $18.91 14%OFF | CTS 14 inch Vacuum Tubeless Tire 3.00-10 / 14x3.2 fits Electric vehicle Electric Scooters e-Bike 14x3.2 300-10 Explosion-proof

https://a.aliexpress.com/_mrpNLPQ

 

For those that have installed a 3 inch, you think this will be too tight?

[houseofjob]

On 9/13/2022 at 4:46 PM, thendless said:

I noticed this 3.2 inch tire on aliexpress: US $18.91 14%OFF | CTS 14 inch Vacuum Tubeless Tire 3.00-10 / 14x3.2 fits Electric vehicle Electric Scooters e-Bike 14x3.2 300-10 Explosion-proof

https://a.aliexpress.com/_mrpNLPQ

For those that have installed a 3 inch, you think this will be too tight?

"-10" this means 10 inch rim, and MTen3 is 6.5 inch rim. You need to match the rim diameter bare minimum.

Edited September 14, 2022 by houseofjob

[EMA]

9 hours ago, houseofjob said:

"-10" this means 10 inch rim, and MTen3 is 6.5 inch rim. You need to match the rim diameter bare minimum.

you are too obsessed with MTEN4 right now ,  this is mcm5 topic

 

[EMA]

14 hours ago, thendless said:

I noticed this 3.2 inch tire on aliexpress: US $18.91 14%OFF | CTS 14 inch Vacuum Tubeless Tire 3.00-10 / 14x3.2 fits Electric vehicle Electric Scooters e-Bike 14x3.2 300-10 Explosion-proof

https://a.aliexpress.com/_mrpNLPQ

 

For those that have installed a 3 inch, you think this will be too tight?

should fit but you need a lot of shell cut

[thendless]

3 hours ago, EMA said:

should fit but you need a lot of shell cut

Ya i measured the 80mm width. It seems like I would have to cut a lot of the shell width wise to make it fit. I'm a little worried that the diameter would also be too large and would rub on the upper parts of the shell. I think ill just have to settle for the 14x3.0 

[EMA]

13 minutes ago, thendless said:

Ya i measured the 80mm width. It seems like I would have to cut a lot of the shell width wise to make it fit. I'm a little worried that the diameter would also be too large and would rub on the upper parts of the shell. I think ill just have to settle for the 14x3.0 

i've the stock tire in the 3" size and love it. it's already huge and need lot of work, you really don't need something bigger

CST-1810 2.75-10  (or 14x3.0)

Edited September 14, 2022 by EMA

[houseofjob]

8 hours ago, thendless said:

Ya i measured the 80mm width. It seems like I would have to cut a lot of the shell width wise to make it fit. I'm a little worried that the diameter would also be too large and would rub on the upper parts of the shell. I think ill just have to settle for the 14x3.0 

My bad, @EMA is right, my head was stuck in MTen4 Tire world, then I made a bad turn off the MTen4 highway switching threads 

 

Your CST "14 x 3.2" tire while fitting the MCM5 rim, yeah, all your shell clearance concerns are valid.

First, there's no way to tell the real size of that CST from the listing, because I've found CN tires often lie about non-rim dimensions (rounding to the next whole number just like EUC companies round battery sizes to whole numbers), as I found out in my first post in this thread.

Though there's no way to tell for sure unless you buy this tire and try to fit it, my guess is you're gonna get undershell rub, because that sidewall looks a bit taller/thicker, especially since it's a tubeless, than the sidewall for the CYT "14 x 3" I used.  

FWIW, I was never able to fit a true 3" into my MCM5, simply due to the fact that the 3" wides tend to be 15 going on 16" outer diameter.