Help me understand tyres

[alvinlwh 5894]

New to RC, especially AM parts, so the stupid questions. Trying to get some new shoes for my cars but for some reason, many sellers and manufacturers do not list their wheels/tyres sizes, or at least not in a way that I can understand. 

I am looking specifically for wheels and tyres that can fit:

TT-01

M-Chassis 

And maybe SW-01 

So I had found some that I am interested in but no idea what fitting or size they are and will very much appreciate it if someone can explain them or someone who actually had experience with them. 

They are:

Medial Pro Trace 2.8 Tyres Mounted On Addict 2.85 Black Wheels NT

HPI Mk 10 V2 Wheel Matt Chrome 4.5mm Offset

Ansmann Touring Car Wheel & Tyre Set 26mm Wide 12mm Hex Pre-Glued (this one I know it will probably fit the TT) 

Next question is about Tamiya original M-chassis wheels and tyres. Are the wheels all of the same size and all M-chassis tyres will fit? What is this "60D" that I sometimes see?

Finally, what are foam inserts for? 

[Frog Jumper 3658]

Most buggy and truck tires and wheels are listed by inner diameter and outer diameter, respectively, ie a "2.2" wheel is 2.2" in diameter while the "2.2" tire has a hole in it that is 2.2" is diameter.  Same goes for 2.8, etc.

26mm wheels are tires are smaller and meant for on-road applications.  In those cases, the "26mm" refers to the depth of the wheel, ie front to back thickness.  Diameter is standardized to 1.55" but there are variations.  Most 26mm tires also list the outer diameter so you can see if it fits under your body.

 

[Willy iine 18805]

I forgot most of the info, but I can answer that m-chassis wheels and tires come in different sizes so be sure to check the inner and outer diameters.  

Foam inserts are basically simulated air pressure.   It you want high psi like response, you would use firmer inserts.

When I raced sedans back in the late 90's  I use to have a whole bunch of different tire compounds and inserts for different surface applications including surface material (asphalt, concrete, etc) and temperature.  Like in the morning heat (race) I would use one set, but if the sun comes out strong in the pm, I would use different compound or inserts to match..and change motor settings too..  it was a lot of trial and error and headache and fatigue.    I enjoy driving my cars inside my house these days just by myself.. so controlled, no competetion, no need to think about all that! 

[TurnipJF 9192]

1 hour ago, alvinlwh said:

Next question is about Tamiya original M-chassis wheels and tyres. Are the wheels all of the same size and all M-chassis tyres will fit? What is this "60D" that I sometimes see?

Yes, all Tamiya M-size wheels are of the same size and offset.

(Some M-chassis cars such as the MF-01X Jimni come with standard touring car size wheels, and other manufacturer's M-class wheels and tyres may be different sizes, but let's forget those complications for now.)

In the case of Tamiya tyres, 60D and 55D refer to the outer diameter of the tyre. The inner diameter is the same in both cases, fitting Tamiya M-size wheels. 

Tamiya 60D tyres come in different hardness compounds with different names, such as S-grips and M-grips for example, as well as a kit-standard compound with no particular name, typically just referred to as a 60D radial.

[alvinlwh 5894]

Just now, TurnipJF said:

Tamiya 60D tyres come in different hardness compounds with different names, such as S-grips and M-grips for example, as well as a kit-standard compound with no particular name, typically just referred to as a 60D radial.

Oh dear.... You had just opened up another can of worms, more questions from me. S & M (no puns intended), I can understand. What about slicks and radials? Which is suitable for what? Or specifically, which will be more suitable for me? I never run on carpet, always outside on tarmac.

Sorry for all the stupid questions. 

[alvinlwh 5894]

12 minutes ago, Willy iine said:

Foam inserts are basically simulated air pressure.   It you want high psi like response, you would use firmer inserts.

So... Let me guess, usually foam for on-road and no foam for off road? That could explain why my on road set is wearing so fast, like an under inflated tyre. 

[alvinlwh 5894]

23 minutes ago, Frog Jumper said:

Most buggy and truck tires and wheels are listed by inner diameter and outer diameter, respectively, ie a "2.2" wheel is 2.2" in diameter while the "2.2" tire has a hole in it that is 2.2" is diameter.  Same goes for 2.8, etc.

Oh dear, my reply seem to have disappeared. Apologies if it somehow appeared and become a double post. 

In that case, the first example don't seem to make sense. The tyre seem to be smaller than the wheel? 

Medial Pro Trace 2.8 Tyres Mounted On Addict 2.85 Black Wheels NT

[alvinlwh 5894]

26 minutes ago, Frog Jumper said:

26mm wheels are tires are smaller and meant for on-road applications.  In those cases, the "26mm" refers to the depth of the wheel, ie front to back thickness.  Diameter is standardized to 1.55" but there are variations.  Most 26mm tires also list the outer diameter so you can see if it fits under your body.

 

So if XXmm will be road/touring car tyres and X.X(inch) will be buggy? 

[Willy iine 18805]

2 hours ago, alvinlwh said:

So... Let me guess, usually foam for on-road and no foam for off road? That could explain why my on road set is wearing so fast, like an under inflated tyre. 

I can't generalize "on" and "off road" because there are so many different driving conditions and variables, but for me usually I do not use inserts in my monster truck tires.  My M38 runs foam inserts.   Most on road I use inserts.. but not all.  

[TurnipJF 9192]

4 hours ago, alvinlwh said:

Oh dear.... You had just opened up another can of worms, more questions from me. S & M (no puns intended), I can understand. What about slicks and radials? Which is suitable for what? Or specifically, which will be more suitable for me? I never run on carpet, always outside on tarmac.

Sorry for all the stupid questions. 

No need to apologise. Your questions aren't stupid at all.

As for recommendations, my M-05 runs well on tarmac wearing M-grips up front, S-grips at the back, blue inserts all round.

Should you ever venture indoors onto carpet though, Ride 55D foams with traction compound work superbly. 

[TurnipJF 9192]

10 minutes ago, alvinlwh said:

So... Let me guess, usually foam for on-road and no foam for off road? That could explain why my on road set is wearing so fast, like an under inflated tyre. 

I tend to use foams on everything other than monster truck tyres. Even if they are totally soft and provide little to no structural support, they help stop sand and dirt from building up in the tyre and throwing it out of balance. 

[Juggular 4964]

1 hour ago, alvinlwh said:

Medial Pro Trace 2.8 Tyres Mounted On Addict 2.85 Black Wheels NT

2.8 diameter is over 70mm.  That means the wheels themselves would be bigger than M-tires. (I overlaid the image)  

They might be close to Monster Beetle tires.  Maybe too big for TT-01, M-chassis, and especially for SW-01 chassis. 

I think I mounted 2.8 inch monster masher for my Mad Bison. But this chassis have a counter gear (at the bottom) to allow bigger tires.  

 

[alvinlwh 5894]

7 minutes ago, Juggular said:

2.8 diameter is over 70mm.  That means the wheels themselves would be bigger than M-tires. (I overlaid the image)  

This alone helped me a great deal. Now I know what the 2.8 means. However, can you explain how 2.8 tyres are mounted on 2.85 wheels? The tyres are smaller than the wheels! Or am I understanding this wrong still? Thanks! 

[Frog Jumper 3658]

2.85” vs 2.8”…

The difference is about 1.25mm. The rubber tire is slightly stretched over the wheel. This is better than the tire being slightly too big.

 

[Juggular 4964]

1 hour ago, alvinlwh said:

2.8 tyres are mounted on 2.85 wheels?

For some time, I thought 2.8 tires mean the tire's diameter being 2.8."  I now know it's the wheel's outer diameter (and tire's inner diameter).  If you thought (like I did) that 2.8 inch diameter tire cannot fit onto 2.85 inch wheel diameter, don't worry. They both mean wheel's outer diameter and tire's inner diameter. (yellow line below)

Like you have noted already, the outer diameter of the tire itself isn't listed, which is inconvenient.  

But since tire says 2.8 and the wheel says 2.85, they mean practically the same diameter. (As Frog Jumper said, 0.05 inch could be just stretched.)

 

[alvinlwh 5894]

1 hour ago, Frog Jumper said:

2.85” vs 2.8”…

The difference is about 1.25mm. The rubber tire is slightly stretched over the wheel. This is better than the tire being slightly too big.

 

 

1 hour ago, Juggular said:

For some time, I thought 2.8 tires mean the tire's diameter being 2.8."  I now know it's the wheel's outer diameter (and tire's inner diameter).  If you thought (like I did) that 2.8 inch diameter tire cannot fit onto 2.85 inch wheel diameter, don't worry. They both mean wheel's outer diameter and tire's inner diameter. (yellow line below)

 

Like you have noted already, the outer diameter of the tire itself isn't listed, which is inconvenient.  

But since tire says 2.8 and the wheel says 2.85, they mean practically the same diameter. (As Frog Jumper said, 0.05 inch could be just stretched.)

Thanks to you both, I understand a little more. Bottom line is... That set I am interested in will fit nothing I own. 😕 As pointed out, the wheel alone is bigger than the M-chassis tyres. Time to look elsewhere. 

Am I right though that the Ansmann set will fit TT and if pushed, the SW-01? 

Absolutely right about the lack of overall size though, I have a jacked up TT01 and it can (and I actually want it to) take a bigger buggy tyre. 

[TurnipJF 9192]

38 minutes ago, alvinlwh said:

Am I right though that the Ansmann set will fit TT and if pushed, the SW-01? 

Yes indeed. I use those Ansmann wheels and tyres on several of my touring chassis including my TT.