Re: eight inch wheels

The difference is more extreme than you find in auto wheel sizes, but for all those folks who love their boats like they love their babies, I can remember going for a bike ride in the city with my little girl on her little bike and she was doing great until we went over a badly made ramp through the corner curb on a street. My wheels were 26" and I didn't even really notice it, but her's were 14" and she got bounced good enough that her feet came off the pedals and she went down. We were going very slow and no problems for her, but lessons learned for both of us, and bigger is better.

Cheers, Brian


--- Inbolger@yahoogroups.com, "Jon n Wanda" <windyjon@...> wrote:
>
> I find this thread to be degenerating to the point of being like Gorila Glue VS Epoxy both will work but one is better and in the case of glues epoxy is cheaper. For a heavy old Dorset day cabin I once had the trailer had 12" wheels I changed to 14s it trailered better. My Lightning trailer had 14s and the new one will to with a droped axle. The lightning is #720. Why I will tell you. No mater what road you are on there will always be something be it a pothile exspantion joint bed frame retread what ever. The bigger tire is always better when you have no choice. If you look at the boat you have as a through away boat use what ever size you want. It is your investment to burn when you want.
>
> Jon
>
> --- Inbolger@yahoogroups.com, Pierce Nichols <rocketgeek@> wrote:
> >
> > 1) I said heat dissipation, not bearing temperature. These are significantly
> > different things and their relationship is complex.
> > 2) Palmgren's formula states that drag torque for lubricated rolling element
> > bearings is proportional to the 2/3 power of wheel speed, which implies that
> > the heat generation is proportional to the 5/3 power of wheel speed (since
> > power is equal to force times velocity). See
> >http://books.google.com/books?id=0XYE2p0QyFwC&pg=PA193&lpg=PA193&dq=bearing+heat+dissipation+speed&source=bl&ots=-F_ZEL48_n&sig=WOOiLsjYTe9FjyNP3TiW-c0r5to&hl=en&ei=6TLASv-SNo_itgPm4aAc&sa=X&oi=book_result&ct=result&resnum=7#v=onepage&q=bearing%20heat%20dissipation%20speed&f=false
> > .
> >
> > -p
> >
> > On Sun, Sep 27, 2009 at 8:23 PM, John Bell <yonderman@> wrote:
> >
> > >
> > >
> > > Your argument seems to assume bearing temperature is 1-to-1 with rpm. 50%
> > > faster does not mean 50% more heat. This is another one of those famous
> > > internet thought experiments. Show me some real data that says this is true.
> > > I've got tons of empirical data derived from personal experience that says
> > > your hypothesis is wrong.
> > >
> > > The easiest way to get bearings to overheat is to over-torque the axle nut
> > > and run them without grease.
> > >
> > > On Sun, Sep 27, 2009 at 11:10 PM, Pierce Nichols <rocketgeek@>wrote:
> > >
>
I find this thread to be degenerating to the point of being like Gorila Glue VS Epoxy both will work but one is better and in the case of glues epoxy is cheaper. For a heavy old Dorset day cabin I once had the trailer had 12" wheels I changed to 14s it trailered better. My Lightning trailer had 14s and the new one will to with a droped axle. The lightning is #720. Why I will tell you. No mater what road you are on there will always be something be it a pothile exspantion joint bed frame retread what ever. The bigger tire is always better when you have no choice. If you look at the boat you have as a through away boat use what ever size you want. It is your investment to burn when you want.

Jon

--- Inbolger@yahoogroups.com, Pierce Nichols <rocketgeek@...> wrote:
>
> 1) I said heat dissipation, not bearing temperature. These are significantly
> different things and their relationship is complex.
> 2) Palmgren's formula states that drag torque for lubricated rolling element
> bearings is proportional to the 2/3 power of wheel speed, which implies that
> the heat generation is proportional to the 5/3 power of wheel speed (since
> power is equal to force times velocity). See
>http://books.google.com/books?id=0XYE2p0QyFwC&pg=PA193&lpg=PA193&dq=bearing+heat+dissipation+speed&source=bl&ots=-F_ZEL48_n&sig=WOOiLsjYTe9FjyNP3TiW-c0r5to&hl=en&ei=6TLASv-SNo_itgPm4aAc&sa=X&oi=book_result&ct=result&resnum=7#v=onepage&q=bearing%20heat%20dissipation%20speed&f=false
> .
>
> -p
>
> On Sun, Sep 27, 2009 at 8:23 PM, John Bell <yonderman@...> wrote:
>
> >
> >
> > Your argument seems to assume bearing temperature is 1-to-1 with rpm. 50%
> > faster does not mean 50% more heat. This is another one of those famous
> > internet thought experiments. Show me some real data that says this is true.
> > I've got tons of empirical data derived from personal experience that says
> > your hypothesis is wrong.
> >
> > The easiest way to get bearings to overheat is to over-torque the axle nut
> > and run them without grease.
> >
> > On Sun, Sep 27, 2009 at 11:10 PM, Pierce Nichols <rocketgeek@...>wrote:
> >
1) I said heat dissipation, not bearing temperature. These are significantly different things and their relationship is complex.
2) Palmgren's formula states that drag torque for lubricated rolling element bearings is proportional to the 2/3 power of wheel speed, which implies that the heat generation is proportional to the 5/3 power of wheel speed (since power is equal to force times velocity). Seehttp://books.google.com/books?id=0XYE2p0QyFwC&pg=PA193&lpg=PA193&dq=bearing+heat+dissipation+speed&source=bl&ots=-F_ZEL48_n&sig=WOOiLsjYTe9FjyNP3TiW-c0r5to&hl=en&ei=6TLASv-SNo_itgPm4aAc&sa=X&oi=book_result&ct=result&resnum=7#v=onepage&q=bearing%20heat%20dissipation%20speed&f=false.

-p

On Sun, Sep 27, 2009 at 8:23 PM, John Bell<yonderman@...>wrote:


Your argument seems to assume bearing temperature is 1-to-1 with rpm. 50% faster does not mean 50% more heat. This is another one of those famous internet thought experiments. Show me some real data that says this is true. I've got tons of empirical data derived from personal experience that says your hypothesis is wrong.

The easiest way to get bearings to overheat is to over-torque the axle nut and run them without grease.

On Sun, Sep 27, 2009 at 11:10 PM, Pierce Nichols<rocketgeek@...>wrote:

Cars tend to have much larger wheels... even my little Honda Fit has 14" rims; I don't think there are any regular production cars with smaller wheels than that. I don't have enough data or experience to really evaluated Dick's assertions, but they're not obviously bogus. At a given speed, the 8" wheel is spinning 50% faster than an equivalent 12" wheel, and therefore generating at least 50% more heat in the bearings. If you're using your bearings &c within their rated limits, you should be fine, of course.

-p



On Sun, Sep 27, 2009 at 7:55 PM, John Bell<yonderman@...>wrote:


I towed a trailer home from San Angelo that had terrible tires. It's the sun that destroys tires out there.

Your argument sounds specious to me. Unless your car tires are melting away faster too, this is bologna.

Chuck???

On Sun, Sep 27, 2009 at 10:34 PM, dickpensil<dickpensil@...>wrote:

You guys really covered the details pertaining to wheel size. One thing you didn't mention is that temperature is a huge factor. In the summer the black top can really get hot here in Abilene. The temperature can get into the mid to hight 100's so you can imagine what the roadway temperature is. With that little wheel spinning so fast and the combined heat from friction, air temperature plus the road temperature it doen't take long to really heat up.

I would suggest the largest wheel you can get in high temperature regions. There isn't a decent lake close to here so not only do we have the above facters to deal with but they need to survive long hauls in really adverse conditons. Small wheels don't survive here too well.

Dick









Another option (or additional step) is to use as good a grease in the bearings
that you can get. Synthetic greases withstand high temps better.

----- Original Message -----
From: "dickpensil" <dickpensil@...>
Sent: Sunday, September 27, 2009 7:34 PM


> You guys really covered the details pertaining to wheel size. One thing you
> didn't mention is that temperature is a huge factor. In the summer the black
> top can really get hot here in Abilene. The temperature can get into the mid
> to hight 100's so you can imagine what the roadway temperature is. With that
> little wheel spinning so fast and the combined heat from friction, air
> temperature plus the road temperature it doen't take long to really heat up.
>
> I would suggest the largest wheel you can get in high temperature regions.
> There isn't a decent lake close to here so not only do we have the above
> facters to deal with but they need to survive long hauls in really adverse
> conditons. Small wheels don't survive here too well.
Your argument seems to assume bearing temperature is 1-to-1 with rpm. 50% faster does not mean 50% more heat. This is another one of those famous internet thought experiments. Show me some real data that says this is true. I've got tons of empirical data derived from personal experience that says your hypothesis is wrong.

The easiest way to get bearings to overheat is to over-torque the axle nut and run them without grease.

On Sun, Sep 27, 2009 at 11:10 PM, Pierce Nichols<rocketgeek@...>wrote:

Cars tend to have much larger wheels... even my little Honda Fit has 14" rims; I don't think there are any regular production cars with smaller wheels than that. I don't have enough data or experience to really evaluated Dick's assertions, but they're not obviously bogus. At a given speed, the 8" wheel is spinning 50% faster than an equivalent 12" wheel, and therefore generating at least 50% more heat in the bearings. If you're using your bearings &c within their rated limits, you should be fine, of course.

-p



On Sun, Sep 27, 2009 at 7:55 PM, John Bell<yonderman@...>wrote:


I towed a trailer home from San Angelo that had terrible tires. It's the sun that destroys tires out there.

Your argument sounds specious to me. Unless your car tires are melting away faster too, this is bologna.

Chuck???

On Sun, Sep 27, 2009 at 10:34 PM, dickpensil<dickpensil@...>wrote:

You guys really covered the details pertaining to wheel size. One thing you didn't mention is that temperature is a huge factor. In the summer the black top can really get hot here in Abilene. The temperature can get into the mid to hight 100's so you can imagine what the roadway temperature is. With that little wheel spinning so fast and the combined heat from friction, air temperature plus the road temperature it doen't take long to really heat up.

I would suggest the largest wheel you can get in high temperature regions. There isn't a decent lake close to here so not only do we have the above facters to deal with but they need to survive long hauls in really adverse conditons. Small wheels don't survive here too well.

Dick






Cars tend to have much larger wheels... even my little Honda Fit has 14" rims; I don't think there are any regular production cars with smaller wheels than that. I don't have enough data or experience to really evaluated Dick's assertions, but they're not obviously bogus. At a given speed, the 8" wheel is spinning 50% faster than an equivalent 12" wheel, and therefore generating at least 50% more heat in the bearings. If you're using your bearings &c within their rated limits, you should be fine, of course.

-p

On Sun, Sep 27, 2009 at 7:55 PM, John Bell<yonderman@...>wrote:


I towed a trailer home from San Angelo that had terrible tires. It's the sun that destroys tires out there.

Your argument sounds specious to me. Unless your car tires are melting away faster too, this is bologna.

Chuck???

On Sun, Sep 27, 2009 at 10:34 PM, dickpensil<dickpensil@...>wrote:

You guys really covered the details pertaining to wheel size. One thing you didn't mention is that temperature is a huge factor. In the summer the black top can really get hot here in Abilene. The temperature can get into the mid to hight 100's so you can imagine what the roadway temperature is. With that little wheel spinning so fast and the combined heat from friction, air temperature plus the road temperature it doen't take long to really heat up.

I would suggest the largest wheel you can get in high temperature regions. There isn't a decent lake close to here so not only do we have the above facters to deal with but they need to survive long hauls in really adverse conditons. Small wheels don't survive here too well.

Dick





I towed a trailer home from San Angelo that had terrible tires. It's the sun that destroys tires out there.

Your argument sounds specious to me. Unless your car tires are melting away faster too, this is bologna.

Chuck???

On Sun, Sep 27, 2009 at 10:34 PM, dickpensil<dickpensil@...>wrote:

You guys really covered the details pertaining to wheel size. One thing you didn't mention is that temperature is a huge factor. In the summer the black top can really get hot here in Abilene. The temperature can get into the mid to hight 100's so you can imagine what the roadway temperature is. With that little wheel spinning so fast and the combined heat from friction, air temperature plus the road temperature it doen't take long to really heat up.

I would suggest the largest wheel you can get in high temperature regions. There isn't a decent lake close to here so not only do we have the above facters to deal with but they need to survive long hauls in really adverse conditons. Small wheels don't survive here too well.

Dick


You guys really covered the details pertaining to wheel size. One thing you didn't mention is that temperature is a huge factor. In the summer the black top can really get hot here in Abilene. The temperature can get into the mid to hight 100's so you can imagine what the roadway temperature is. With that little wheel spinning so fast and the combined heat from friction, air temperature plus the road temperature it doen't take long to really heat up.

I would suggest the largest wheel you can get in high temperature regions. There isn't a decent lake close to here so not only do we have the above facters to deal with but they need to survive long hauls in really adverse conditons. Small wheels don't survive here too well.

Dick