Magic Pie III puncture proof tyres

[Shane]

Hi!
I am about to buy puncture proof tyres for my Magic Pie III trike. It is a KMX trike that I've made electric by fitting a Magic Pie III rear wheel.

2 front wheels
16" wheel diameter  = 305mm 
inside wheel width (wall to wall) about 20mm

1 back wheel
Magic Pie 20" cast wheel diameter  = 1265mm 
Magic Pie inside wheel width (wall to wall)= 31mm (I saw MagicMonkey had given this size on another post)

At the moment I have Schwalbe tyres a 20x2,0 Schwalbe Big Apple tyre on the rear
and 16x2,0 Schwalbe Big Apple tyres at front
http://www.kmxkarts.se/models.php?model=2

The Magic pie III inside wheel width is rather large.

I could not find any tyres here that fit the back wheel:
https://www.smartadack.se/produkt/cykeldack/ Tips?

I asked this company as well:
http://www.greentyre.com/about.php

[Bikemad]

Hi Shane,

The 20" cast rim is probably better suited for use with 16" moped or motorcycle tyres which centre themselves correctly on the rim, unlike 20" bicycle tyres which do not always seat themselves properly in the rim and are often not concentric with the axle.

Moped and motorcycle tyres typically use the inside of the tyre as the diameter measurement, whereas bicycle tyres sizes relate to the outside diameter of the tyre.

A 2.25x16 motorcycle tyre will have a larger outer diameter (and will also be wider) than your 20x2,0 Schwalbe Big Apple tyre.

Being pneumatic, they are obviously not 100% puncture proof, but a moped or motorcycle tyre can usually withstand a lot more load and abuse than a typical bicycle tyre.

Unfortunately, due to Photobucket's ridiculous change in their terms and conditions, all the lovely pictures in MonkeyMagic's post that previously demonstrated the difference in tyre sizes are no longer visible.

Alan
 

Hey chaps

This will apply to anyone with a cast, or smaller GM wheel. However, there are MANY options available for a heap of wheel options and different vehicle types.

I have continued my hunt.... And by word of mouth from a local supplier here - recommended contacting SAVA tires. He passed me a website and told me to write back to him with my size preference.

The local supplier told me to look for the INSIDE diameter, not the overall diameter - as I could find a much better fit.
GM 20" Casted wheel = 16" Inside diameter. Searching for this size has generated many more options.

So if you live in Europe, bonus!! And you are probably laughing at my post wondering why I had never heard of them before.

Anyway it is really difficult to find different tire options in Australia, so I assumed other people could have the same problem elsewhere.
Here's their site in Europe, and they have WW presence.

http://www.savatech.eu/tyres

I've been recommended these for my cast 20" wheels:
2 1/2 -16    42 J    TL/TT REINF.    
2 3/4 -16    46 J    TL/TT REINF.    

16" inside diamter, 2.5inch for front, 2.75inch for the rear. They look super sporty but not sure what they will be like in the wet. I take it easy anyway and prefer the 'slicker' look

http://www.savatech.eu/tyres/moped/sport.html

Cheers MM

[Shane]

Thank you Alan as always, for your well-informed and comprehensive answer.

Greentyre answered yesterday:

"Hi Shane
 
Thank you for your e-mail.
 
We do have 16” (Tornado) and 20” (Blizzard/Polyair) tyres in our current range which we can offer depending upon your internal rim fitting but I believe the tread width is narrower than you currently have.
 
It looks like you require more specific tyres with a wider tread for your trike and I’m afraid that is not something we currently offer in our range.
 
We could look at a tooling, but as you require only 3 tyres then this would be a very expensive option for you.
 
If I can be of any further assistance please do not hesitate to contact me.
 
Many thanks
Sue"

Here are the puncture proof tyres from UK greentyre: http://www.greentyre.com/bicycle-tyres.php

The 16" Tornado tyres are 16 x 1.75 with and internal rim size of 23 - 25

The 20" Blizzard tyres are 20 x 1.75 or 20 x 2.125 with internal rim sizes of 23 - 25 and 27 - 28 respectively.

This picture posted before, is helpful. the "inner rim width" is as in the picture below:


I am still waiting for a reply from China https://www.goldenmotor.com/ about the size of the Magic Pie III internal rim, UK Kmx karts for an exact size of the internal rims for the 16" wheels. I am a European living in Sweden and also still waiting for the Swedish tyre firm https://www.smartadack.se/produkt/cykeldack/ to answer.

Does anyone have an opinion on fitting the above mentioned 16” (Tornado) and 20” (Blizzard/Polyair) tyres?

best
Shane

[Shane]

KMX answered:

"The internal rim diameter for the front wheels of the KMX Typhoon are 18mm."

 


but it seems a Swedish company  https://www.smartadack.se/produkt/cykeldack/ could get 16 inch, 16-18 mm internal rim size tyres. Just a case of waiting for golden motor to answer now. KMX cannot mean anything other than "inner rim width" when they say "internal rim diameter".

[GM Canada]

I did measure the rim widths back in 2010. Maybe this thread will help.

https://goldenmotor.com/SMF/index.php?topic=2308.msg12477#msg12477

Gary

[Shane]

I did measure the rim widths back in 2010. Maybe this thread will help.

https://goldenmotor.com/SMF/index.php?topic=2308.msg12477#msg12477

Gary

cool, that would still mean I could get could get 16 inch, 16-18 mm internal rim size tyres from Sweden https://www.smartadack.se/produkt/cykeldack/ .

And as the inner rim width seems to be 1.5 inches or 38.1 mm I am a little puzzled. It does not seem that large. Did you measure the "inner rim width" of a 20 inch cast as shown in the picture below?:

[Shane]

Hmm, I see now
is not the inner rim width.

[Shane]

Hmm, I see now
is not the inner rim width.

eyeballing it. I get 8/10 of an inch + 4/10 inch = 2.032cm+1.016cm=3.48cm=1.37inches

Still way too wide for any of the puncture proof tyres I've found so far 

a reduction in that measurement by 6 mm seems a little too much to hope for but I'll have to wait and see what golden motor say about their official "inner rim diameter"

[Bikemad]

eyeballing it. I get 8/10 of an inch + 4/10 inch = 2.032cm+1.016cm=3.48cm=1.37inches

Still way too wide for any of the puncture proof tyres I've found so far 

a reduction in that measurement by 6 mm seems a little too much to hope for, I'll see what golden motor say about their official "inner rim diameter"

If you had a set of solar powered digital calipers you wouldn't need to "eyeball" it, you could simply measure the rim using the internal jaws to determine the exact internal measurement (assuming it was light enough to enable it to work).

My digital calipers are battery powered, but I have to remove the battery when I've finished using them or the battery seems to go flat over time even though they are turned off. 

Alan
 

[Shane]

eyeballing it. I get 8/10 of an inch + 4/10 inch = 2.032cm+1.016cm=3.48cm=1.37inches

Still way too wide for any of the puncture proof tyres I've found so far 

a reduction in that measurement by 6 mm seems a little too much to hope for, I'll see what golden motor say about their official "inner rim diameter"

If you had a set of solar powered digital calipers you wouldn't need to "eyeball" it, you could simply measure the rim using the internal jaws to determine the exact internal measurement (assuming it was light enough to enable it to work).

My digital calipers are battery powered, but I have to remove the battery when I've finished using them or the battery seems to go flat over time even though they are turned off. 

Alan

I'm waiting to get my own battery powered calipers in the post from China but the thing is I'd like to avoid having to take the tyre off. Does the picture you posted of a caliper measuring 25.4 mm represent a 20" Magic Pie cast wheel? If it does a polyair from green tyre would probably fit. 

[Bikemad]

No, unfortunately it doesn't, I was just trying to illustrate how to measure the internal gap. 

I did find another UK supplier of airless tyres, tannus.co.uk who may have suitable tyres for your front 16" rims, but I couldn't see any prices, which presumably means they will be very expensive.
As the saying goes, "If you have to ask the price, then you probably can't afford it!"

Check out the available sizes here.

Alan
 

[Shane]

No, unfortunately it doesn't, I was just trying to illustrate how to measure the internal gap. 

I did find another UK supplier of airless tyres, tannus.co.uk who may have suitable tyres for your front 16" rims, but I couldn't see any prices, which presumably means they will be very expensive.
As the saying goes, "If you have to ask the price, then you probably can't afford it!"

Check out the available sizes here.

Alan

wow, Thanks. The min velo 16" tyres seem like they may fit.
and the 20"   2.0   (51-406)   -   50   675   32-34mm means it is possible they may have one for the Magic Pie that fits (y)

[Bikemad]

Unfortunately the Tannus tyres are not suitable for the 20"cast rim even if they were available in the correct rim width and diameter, as there is nothing on the inside of the cast rim for the tyre retaining pins to locate into.

Check out their installation video for more details.

I would simply use a 16" motorcycle/scooter tyre on the rear which should be a lot more resistant to punctures than a bicycle tyre and it will also fit the rim better too. 

Alan
 

[Shane]

Hi Alan, thanks. Good to know.
Various other sources on the Internet are not super positive about solids either. E.g.
https://www.youtube.com/watch?v=Yca1g1eooqo

I'll definately give 16" motorcycle/scooter tyre on the rear some thought but sticking with Schwalbe pneumatics might be a good bet as well. After all that investigation, I have heard they are actually pretty puncture resistant for conventional tyres. I guess my time might right now be better spent insulating my e-bike against the cold and the wet.

best
Shane

[Shane]

By the way I wrote to golden motor in China:

Date: 2017-11-28 21:57
Subject: inner rim width of 20" Magic Pie cast wheel
Hi!
 do you know the internal rim size of a 20" cast bicycle Magic Pie wheel?
This picture posted on the internet, is helpful. the "inner rim width" is as in the picture below:


I would like to find puncture proof tyres but need to know the inner rim width of all my tyres.

best
Shane

and got this reply:

Dear Shane,

Have a nice day!

Usually, the size of 20" is 1.75-1.95CM or 1.95-2.125CM.

Best Regards!