Popular Post greentung Posted September 4, 2019 Popular Post Share Posted September 4, 2019 I modded my MCM5 to ride on Chao Yang 14x2.5" wide tire. The stock MCM5 is 14x2.125" wide. I am used to wider tires (mten3, Z10, Nikola). I was not comfortable with the stock MCM5 tire. @RoCan modded his MCM5 for the 2.5" wide tire. This tire mod require cutting away a portion of the front and back shell cover along with the outer edges of the wheel well. I took @RoCan advice and made sure I cut away enough material so there is ample clearance for the wide tire. The clearance I was shooting for was 3" from edge to edge. This means the last two bottom shell screw holes were cut off. I plan to use metal or moldable plastic tabs to hold the cover bottom edges to the shell. The plan was to do rudimentary cut, install tire, and ride test. Then clean the cuts, seal any gaps, and trim out. Currently at the ride testing phase. Initial observations: The 14x2.5" tire is actually 14.5" diameter. The recommended pressure is 35-45 psi. The tire need to be inflated at or above 33 psi. Anything less and the tire rubs against the top inner wheel well. I believe under inflation causes the tire to expand diameter wise. Whereas higher psi the tire widens (flatten). I am testing it at 43psi which is on the hard side. I feel it going over 4" curve. I plan to reduce the tire pressure in 2 psi increment to find the lowest useable pressure. I took the wheel to work. The ride quality even with hard tire pressure is fantastic. The combination of wider tire and the tire itself gives the wheel very good control. The feeling of falling over on tight turns is gone. It handles like an mten3 at low speed. At higher speed (22+ mph) it gets a little squirrelly due to high tire pressure tracking road. I believe this can be resolved by dropping the pressure below 38 psi. I am glad I did this mod. It has turned my MCM5 into a mini Nikola. Chao Yang 14x2.5" tire versus stock 14x2.125" tire. 10 Quote Link to comment Share on other sites More sharing options...
mrelwood Posted September 4, 2019 Share Posted September 4, 2019 That must be an excellent mod! No place for narrower than 2.5” tires in EUCs! 1 Quote Link to comment Share on other sites More sharing options...
RoCan Posted September 5, 2019 Share Posted September 5, 2019 Looks like you’ve gone to town. Good job! I preserved the lower screw holes so my gap is still tight, although not rubbing. I’ve been running at 35psi, I’m 210lbs. Seems to be just soft enough. Any higher is too hard for me. Sounds like I’ll need to check on this quite frequently if you’re getting rubbing below 33psi. I had only been using on asphalt but took it off road last week. If no big bumps I have to agree with @Jorge RT and @trya, a lot of fun! It just sticks to your feet and feels so light. Reminds me of driving a classic mini car, it becomes an extension of your body. Watch your speed though, easy to go faster with the extra stability and as @mrelwood explained to me, the bigger diameter means you’re going faster than the app states. Have fun on your new wheel! 2 Quote Link to comment Share on other sites More sharing options...
greentung Posted September 5, 2019 Author Share Posted September 5, 2019 Thanks @RoCan. I've gone down to 38psi and it's running ok. I am 170lbs. I wonder if all your riding has worn down the center tread enough that the rubbing issue went away. I like the wide MCM5 so much now that it has replaced my beloved mten3 as the 'fun messing around' wheel. I agree it has become an extension of my leg. I can almost just stay in one spot with it like the mten3. 3 Quote Link to comment Share on other sites More sharing options...
RoCan Posted September 5, 2019 Share Posted September 5, 2019 40 minutes ago, greentung said: Thanks @RoCan. I've gone down to 38psi and it's running ok. I am 170lbs. I wonder if all your riding has worn down the center tread enough that the rubbing issue went away. I like the wide MCM5 so much now that it has replaced my beloved mten3 as the 'fun messing around' wheel. I agree it has become an extension of my leg. I can almost just stay in one spot with it like the mten3. I’ve not ridden enough for any wear on the tyre. Is the rubbing you experienced at low psi to the interior shell when riding straight or when turning/shifting weight? Funnily enough I was going to buy an Mten3 but went for the MCM5 due to low stock in Europe. I’m unlikely to but one now. Quote Link to comment Share on other sites More sharing options...
greentung Posted September 5, 2019 Author Share Posted September 5, 2019 The tire rubbing is in the wheel well. It's the same riding straight or turning. It doesn't affect the performance of the wheel. We're talking light contact when the tire pressure is below the recommended range. I can hear it, especially when the tire picks up sand and grit. Did you use the 14x2.5" inner tube that came with the tire? Quote Link to comment Share on other sites More sharing options...
RoCan Posted September 5, 2019 Share Posted September 5, 2019 Yeah I used the inner tube that came with. I get the grit rubbing but I’ve not filed down the reveal fully yet. Maybe it won’t make a difference as you’ve filed quite a bit. Don’t notice it at high speed though. 1 Quote Link to comment Share on other sites More sharing options...
greentung Posted September 12, 2019 Author Share Posted September 12, 2019 (edited) Update: I've commuted for a week on my modded MCM5. I am satisfied the mod. Starting phase two; clean, seal, and make presentable. Some observations: The 'fake' air vents on the MCM5 actually does vent some air through the channel. The opening is not very big. But it's there at the top vent on both end. The handle post doesn't drain out of shell. Will have to make sure water doesn't get into the handle holes. Added plastic trim to holding and gripping handle easier. Painted pedals matte black and removed the silver intake tabs from the slots. It didn't really serve any function other than looks. I might put black/silver reflectors in the slots. Next is making a rubber mud flap for the rear. Edited September 14, 2019 by greentung 3 Quote Link to comment Share on other sites More sharing options...
Rywokast Posted September 12, 2019 Share Posted September 12, 2019 On 9/4/2019 at 11:05 AM, mrelwood said: That must be an excellent mod! No place for narrower than 2.5” tires in EUCs! I prefer 2.125.. more stability is not more desirable to me Quote Link to comment Share on other sites More sharing options...
Popular Post greentung Posted September 26, 2019 Author Popular Post Share Posted September 26, 2019 I had some left over wood wrap from my Nikola+ mod project. So, I wrapped the MCM5. Vinyl wrap on the MCM5 doesn't block the LEDs like the Nikola. However, the semi fake air vents posed problems for my newbie wrapping skills. The wrap was not as cleaned as I'd like. But from a distance it looks fine. I have temporary foam padding for the MCM5 circle bulge cutout. Will replace it with thinner foam padding so that it will be flush with the rest of the leg pad. 9 Quote Link to comment Share on other sites More sharing options...
RoombaRider Posted January 2, 2020 Share Posted January 2, 2020 (edited) I did the upgrade as well. Took some photos to show the process. Improvement is pretty much across the board. Better cushioning, grip, obstacle jumping, and even tight turns (higher pedal clearance) Note: (Among other things) i had to bend the valve stem in order to fit, since the original is turned 90º. Link to where I got the tire from: 2.5" Tire - Amazon Edited January 2, 2020 by RoombaRider 3 Quote Link to comment Share on other sites More sharing options...
alcatraz Posted January 3, 2020 Share Posted January 3, 2020 I'm hesitating to get an MCM5 instead of my V8 because of ride quality, ability to grip the wheel and pedal height. What do you think of the pedal height with the tire mod. Is the turning circle small now? I hear it was a problem. What about going down curbs? Or up? Does the shell rub a lot still? Quote Link to comment Share on other sites More sharing options...
houseofjob Posted January 3, 2020 Share Posted January 3, 2020 (edited) 9 hours ago, RoombaRider said: Note: (Among other things) i had to bend the valve stem in order to fit, since the original is turned 90º. woah, woah, woah, ..... please explain how you did this, as I have a whole stash of 14" inner tubes with valves going the wrong way that I would love to correct to the proper 0º, thanks in advance! Edited January 3, 2020 by houseofjob 2 Quote Link to comment Share on other sites More sharing options...
RoombaRider Posted January 3, 2020 Share Posted January 3, 2020 17 hours ago, houseofjob said: woah, woah, woah, ..... please explain how you did this, as I have a whole stash of 14" inner tubes with valves going the wrong way that I would love to correct to the proper 0º, thanks in advance! I wish i had a clever solution for ya, but i just hit it with a plastic hammer while it was already loaded into the rim. The tube will crease and bend but the shape doesn't really matter, so long as it doesn't leak. I tried holding the valve stem with a vice while bending, but it didn't work any better than the mallet. Can't heat it up with a torch either as that will melt the connection to the rubber. 1 Quote Link to comment Share on other sites More sharing options...
RoombaRider Posted January 3, 2020 Share Posted January 3, 2020 18 hours ago, alcatraz said: I'm hesitating to get an MCM5 instead of my V8 because of ride quality, ability to grip the wheel and pedal height. What do you think of the pedal height with the tire mod. Is the turning circle small now? I hear it was a problem. What about going down curbs? Or up? Does the shell rub a lot still? I won't comment on MCM5 vs. other wheels, since there's a lot of personal preference in there (MCM5 isn't necessarily my favorite, but it has its advantages). Pedal height is higher, maybe 1/2-3/4" or so. I don't know if it was really a problem before, but tight turns are easier with no pedal draggy now. Trimming back the shell is the first step towards going up curbs. I don't know why the plastic covers so much of the wheel, but it is excessive and it will just break on its own if you don't preemptively trim it anyway. The new tire requires some simple and easy trimming to the inside as well. After trimming and new tire, there is a big increase in tire exposure and going up ~5-6" square curbs is possible without hitting the shell. I can get up obstacles as high as 9" or so if there's a little slope to it. I ride MTB trails, so obstacle jumping is one of my main concerns. Quote Link to comment Share on other sites More sharing options...
RoCan Posted January 8, 2020 Share Posted January 8, 2020 Anyone know a seller in Europe of: 14 x 2.5 angled valve inner tube for MCM5? Thanks Quote Link to comment Share on other sites More sharing options...
Delmeekc Posted February 9, 2020 Share Posted February 9, 2020 Can you share the ISO tyre size please xx/254 and also the measured width with some verniers inflated above the 33psi please, could you measaure the outer tread and also in one of the gaps between the side treads. Thanks. Quote Link to comment Share on other sites More sharing options...
jaiong Posted August 14, 2020 Share Posted August 14, 2020 Can u share a schematic or sketch of the plastic cut on the shell, required for the mod? Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.