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memphis23
10-09-2012, 04:43 PM
Single axle trailer, 1988 pro-star Tire size now is 205-75-14 with a load rating c I would like to go to a 215-75-15 .

Has anyone ever done this before? I am looking to gain some towing capacity

memphis23
10-09-2012, 08:42 PM
cant believe no one has an opinion. Guess I will go with the 857 Kumho and stay on 14"

mzimme
10-09-2012, 09:16 PM
That tire would be a larger overall diameter on the 15" than the 14" wheel. If you go with a larger diameter tire you need to cut down on the aspect ratio of the tire (the middle number) to keep the same overall diameter.

215 is millimeters wide of the tire.
75 is 75% of the width in sidewall height
15 is the diameter of the wheel.

Miss Rita
10-09-2012, 09:36 PM
The larger size will raise your trailer about 3/4". Maybe that's good, maybe not.

j.mccreight@hotmail.com
10-09-2012, 09:37 PM
I don't think you'll find a 215 75r15 in a "trailer" tire you will need to goto a 225 75r15, either 15" you choose will be wider and taller than the 205 75r14, besides having to purchase new wheels you might run into clearance issues. Personally I would find a D load in the oem 14" size and call it good.

Traxx822
10-09-2012, 10:43 PM
I don't think you'll find a 215 75r15 in a "trailer" tire you will need to goto a 225 75r15, either 15" you choose will be wider and taller than the 205 75r14, besides having to purchase new wheels you might run into clearance issues. Personally I would find a D load in the oem 14" size and call it good.

I ran into this same situation couple weeks ago when I put new tires on my trailer. One side was an original from 1995. :eek: I bought some Carlisle's because I didn't want to go through all the hassle and have some clearance issue that caused more damages by going with a much "cooler looking" 15" wheel. And full size tire. Then I was told the Carlisle's I bought were crap and the tread seperates from the tire often. And i'm about to drive my new carlisle's 2000 miles. So maybe I should stay out of this thread.

j.mccreight@hotmail.com
10-09-2012, 11:24 PM
I ran into this same situation couple weeks ago when I put new tires on my trailer. One side was an original from 1995. :eek: I bought some Carlisle's because I didn't want to go through all the hassle and have some clearance issue that caused more damages by going with a much "cooler looking" 15" wheel. And full size tire. Then I was told the Carlisle's I bought were crap and the tread seperates from the tire often. And i'm about to drive my new carlisle's 2000 miles. So maybe I should stay out of this thread.

I would recommend going to a tire shop or new car dealer and having nitrogen put into the tires, nitrogen maintains psi better doesn't bleed down and the tire runs much cooler thus not increasing psi while driving due to heat, there's a reason why military aircraft, commercial aircraft, most first responders and nascar puts nitrogen in tires. I wouldn't worry to much about your new tires all trailer tire manufacturers have had tire blowouts, tread seperation etc., but thats usually on a tire thats been neglected, dry rotten or just plain old. If you get a flat with nitrogen filled tires no worries simply fill with regular air, on your trip take a look at the tires from time to time to make sure everything is ship shape.

O2BESOHUGE
10-10-2012, 09:28 AM
HERE IS SOMETHING THAT IS HELPFUL!!

http://www.miata.net/garage/tirecalc.html

PUT YOUR ORIGINAL/STOCK TIRE SIZE IN AND THEN PLUG THE NUMBERS OF THE NEW TIRE TIZE IN AND IT COMPARES THE WIDTH AND HEIGHT DIFFERENCES IN EACH TIRE. PRETTY NEAT LITTLE TOOL!! IT SHOULD ANSWER YOUR QUESTION

JAY

thatsmrmastercraft
10-10-2012, 10:07 AM
They are close in size but few manufacturers produce an ST215/75R15

memphis23
10-10-2012, 12:22 PM
@ O2: Wow that is a very helpful tool Thanks!

Phntmski
10-10-2012, 01:03 PM
Back when I bought my 91 PS with a slot it had the wrong prop on it, a smaller, unknown to me brand. I think PO went with a smaller prop to keep from hitting the prop guard on my pos trailer. After getting the right OJ I promptly thrashed it on the prop guard loading back on the trailer. Figured I either needed to raise the bunks or lower the guard . I chose the latter. As a result I was constantly dragging the guard (but no prop damage :D). To help stop the dragging the next time I needed tires I went with 15s and replaced the wheels. Now I seldom drag. All is well. I know this was probably not the right approach but it all seems functional and that's all I need. And they do look kinda cool. :cool:

TxsRiverRat
10-10-2012, 01:13 PM
Another option is to replace the leafsprings with higher ones. mine seldom drags either

sp00ky
10-10-2012, 01:17 PM
Single axle trailer, 1988 pro-star Tire size now is 205-75-14 with a load rating c I would like to go to a 215-75-15 .

Has anyone ever done this before? I am looking to gain some towing capacity

I went from a st205 75 r14 to a st215 75 r14 and it raise it up about 1.5 inches. However, you can't go from 14 to 15 without buying new wheels.

Miss Rita
10-10-2012, 01:56 PM
I went from a st205 75 r14 to a st215 75 r14 and it raise it up about 1.5 inches.

That would be difficult to do, since the 215 is barely 1/2" larger diameter than the 205.

A 215/75-15 tire would be 1.6 inches taller than the 14 incher, but would only raise the trailer about 3/4"

Phntmski
10-10-2012, 02:04 PM
Leaf spring work is a definite option. A PO had already tried that. What I'd really like is a new trailer but that ain't happening any time soon, if ever.

thatsmrmastercraft
10-10-2012, 02:28 PM
If you want more capacity, and IF you have the space, the tire that comes closest, and is readily available is an ST225/75R15. That set-up ends up more than an inch taller and more than 3/4" wider. Wheel would need to be no wider than 6". You would need to do some careful measuring to ensure there would be no rubbing under spring compression.

memphis23
10-10-2012, 05:13 PM
ThatsMr: What do you think of Kumho tires there 205/75/14 857's are D load and 2271 lbs. on total load capacity?

thatsmrmastercraft
10-10-2012, 06:10 PM
ThatsMr: What do you think of Kumho tires there 205/75/14 857's are D load and 2271 lbs. on total load capacity?

They seem to be a decent tire. I have had no direct experience with them. Some will question their not being a true trailer tire, but a commercial tire used as a trailer tire. I am not aware of any issues with them.

FrankSchwab
10-10-2012, 06:10 PM
I would recommend going to a tire shop or new car dealer and having nitrogen put into the tires, nitrogen maintains psi better doesn't bleed down and the tire runs much cooler thus not increasing psi while driving due to heat, there's a reason why military aircraft, commercial aircraft, most first responders and nascar puts nitrogen in tires. I wouldn't worry to much about your new tires all trailer tire manufacturers have had tire blowouts, tread seperation etc., but thats usually on a tire thats been neglected, dry rotten or just plain old. If you get a flat with nitrogen filled tires no worries simply fill with regular air, on your trip take a look at the tires from time to time to make sure everything is ship shape.

Bull-oney.

Plain old air is already mostly Nitrogen (78% Nitrogen, 21% Oxygen, 1% everything else except in the LA Basin), so any effects of pure Nitrogen are only minimal.
Nitrogen may have a slightly lower rate of diffusing through tire rubber, but I haven't seen any authoritative data that shows that to be true. Even if it does, Nitrogen still diffuses out, you still have to check tires with Nitrogen, and you still have to keep the pressure up.
There's certainly no evidence that tires filled with Nitrogen run cooler, and no physical explanation for how it could.
There's some useful arguments for Nitrogen, in that it doesn't support fire, and it doesn't contain any water. Fire is a spurious argument - I can't remember the last time my tires spontaneously burst into flames. Water has a practical consideration, in that it can cause corrosion for components (rim, steel wire in the tire bead, tire pressure monitor, etc) inside the tire.

Pure nitrogen fills are simply a way to fleece some people of the extra $20 in their pocket. If it makes you feel better, go for it - I buy lottery tickets every now and then also.

TxsRiverRat
10-10-2012, 06:21 PM
Pure nitrogen fills are simply a way to fleece some people of the extra $20 in their pocket. If it makes you feel better, go for it - I buy lottery tickets every now and then also.

A little warning would have been nice

http://vipstylecars.com/forums/images/smilies/smiley-rofl.gif

Cloaked
10-10-2012, 07:01 PM
ThatsMr: What do you think of Kumho tires there 205/75/14 857's are D load and 2271 lbs. on total load capacity?I use the Kumho 857 series tire(s) on the same year-era trailer. Like the tire(s) and have had no issues with it. I'll stick with it until they burst into flames....

.

thatsmrmastercraft
10-10-2012, 07:25 PM
I use the Kumho 857 series tire(s) on the same year-era trailer. Like the tire(s) and have had no issues with it. I'll stick with it until they burst into flames....

.

Careful what you ask for.:rolleyes:

j.mccreight@hotmail.com
10-10-2012, 09:06 PM
Bull-oney.

Plain old air is already mostly Nitrogen (78% Nitrogen, 21% Oxygen, 1% everything else except in the LA Basin), so any effects of pure Nitrogen are only minimal.
Nitrogen may have a slightly lower rate of diffusing through tire rubber, but I haven't seen any authoritative data that shows that to be true. Even if it does, Nitrogen still diffuses out, you still have to check tires with Nitrogen, and you still have to keep the pressure up.
There's certainly no evidence that tires filled with Nitrogen run cooler, and no physical explanation for how it could.
There's some useful arguments for Nitrogen, in that it doesn't support fire, and it doesn't contain any water. Fire is a spurious argument - I can't remember the last time my tires spontaneously burst into flames. Water has a practical consideration, in that it can cause corrosion for components (rim, steel wire in the tire bead, tire pressure monitor, etc) inside the tire.

Pure nitrogen fills are simply a way to fleece some people of the extra $20 in their pocket. If it makes you feel better, go for it - I buy lottery tickets every now and then also.

I get it your naturally a skeptical person, have you ever tried nitrogen in your tires? I have used nitrogen in military and commercial applications for many years. There are arguments for and against the use of nitrogen in your average car. Now for the average MCOCD owner nitrogen is probably not for them as this type of person regularly checks their air pressure and then there is what I like to call the walmart vunerables. The walmart vunerable never checks their tires rides around with 10-15 psi underinflated tires and wonder why their tires wear out in 15k miles and then they blame the tire manufacturers for making crap tires.

I will digress and say that nitrogen filled tires still need to be checked regularly as they do diffuse about .5-1 psi (sometimes no loss at all) versus 2-3 psi for your average compressed air filled tire that is contaminated with oil, water, rust and whatever else is sitting in the tank of the compressor at your local walmart or your local quicky mart. These are actual numbers I have measured with my own hands and tools. I would also add the overall condition of the tire dictates how much air or nitrogen diffuses through the rubber and at what rate.

Nitrogen can't fix stupid car owners but it can certaintly make them less stupid with the care of their tire, instead of the tire being 10psi low or more every time they think about getting their oil change which in itself is usually way overdue it will be only about 1.5-3 psi low thus helping maintain their crap tires.

The annoying TPMS light will not come on when the first cold frosty morning hits because you won't "lose" the 2% psi for every 10 degrees of temperature change because the air compressed, think air filled balloon put in freezer and see what happens. I actually have customers that would rather drive to my shop than going to a local gas station and filling up their tires, as they always think there is something wrong with their car when there's nothing wrong it's just a car owner with low air pressure in their tires. I would say nitrogen filled tires run cooler because they maintain proper inflation, tires that are underinflated run hot-much hotter than properly inflated ones, also nitrogen is not affected by outside air temperatures and will maintain more consistent pressure through seasonal variations in temperature. Underinflation is the leading cause of tire failure.

As far as price when you buy a car, tires or just buy the service from me you get lifetime free nitrogen refills even if you buy tires from another retailer at a later date. Thats right free, I have even done customers other vehicles including trailers and their RV's at no cost to them. I'm not trying to sell anyone a nitrogen service I'm just stating what we do at my shop.

So basically for your MCOCD driver nitrogen is not for you but if your a walmart vunerable type nitrogen might just save you some money down the road.

So if you want to hold on to your $20 and check your tires I have no problem with that, the majority of drivers never check their air pressure. I don't play the lottery and I check the tires in my truck weekly and have not had to add nitrogen to my tires in over 3 months thats right no psi loss in 3 months.

And yes I know I misspelled vulnerable to prove my point.

FrankSchwab
10-11-2012, 01:33 AM
Your numbers aren't that different from Consumer Reports (http://news.consumerreports.org/cars/2007/10/tires-nitrogen-.html) numbers. If you blur your eyes a little bit, they report that Nitrogen filled tires lose about 1/3 the pressure over a year compared with air-filled tires (1.3 vs. 3.5 psi), and you're claiming roughly 1/3 (.5 - 1 vs. 2-3). So, if you don't check your tire pressures regularly, a Nitrogen fill will indeed keep the tire pressures higher, for longer.

I prefer to check my tire pressures a couple of times a year, and keep the $20 for my own purposes. As far as the other claimed advantages, I still claim that they're mostly bull-oney.

/frank

memphis23
10-11-2012, 10:23 AM
Anybody heard or know anything about these: http://www.etrailer.com/Tires-and-Wheels/Kenda/AM32669.html

I just put my replacement springs on and they look to be about 1.5" taller than the old springs, so I am pondering taking advantage of the extra space and going with something like the above tire in a 225/75/15 Load range D capacity 2,500 lbs.

j.mccreight@hotmail.com
10-11-2012, 10:26 AM
Anybody heard or know anything about these: http://www.etrailer.com/Tires-and-Wheels/Kenda/AM32669.html

I just put my replacement springs on and they look to be about 1.5" taller than the old springs, so I am pondering taking advantage of the extra space and going with something like the above tire in a 225/75/15 Load range D capacity 2,500 lbs.

if you have the space then ok, 15" is still taller than the 14" by more than 2"

http://www.discounttire.com/dtcs/infoTireMath.dos plug in your numbers

thatsmrmastercraft
10-11-2012, 10:27 AM
Anybody heard or know anything about these: http://www.etrailer.com/Tires-and-Wheels/Kenda/AM32669.html

I just put my replacement springs on and they look to be about 1.5" taller than the old springs, so I am pondering taking advantage of the extra space and going with something like the above tire in a 225/75/15 Load range D capacity 2,500 lbs.

Kenda tires were always decent tires. Package might be a little pricey.....might want to shop around a little. I think I'm at $94 on the Gladiator QR-25 tire. Haven't priced wheels for a bit. At least they have free shipping.

memphis23
10-11-2012, 10:30 AM
I went from a 4 leaf to a 5 leaf and they have a little more of an arch as well. tonight I will get in close and check and see just exactly how much room I have.

I will go ahead and preface this as a stupid question but here goes. If a tire is 2.18" inches taller sitting side by side on the ground it is 2.18"s taller but once it is put on a wheel isn't the clearance needed for a fender well only 1.09"?????

memphis23
10-11-2012, 11:03 AM
ThatsMr: Do you sell tires?

thatsmrmastercraft
10-11-2012, 12:02 PM
ThatsMr: Do you sell tires?

I do indeed.

memphis23
10-11-2012, 12:05 PM
I would much rather buy from a fellow TT than some obscure website. Based on this discussion PM me what you think would work for me best ($). Lets do some business.

Does my above question make any sense? about the clearance being 1.09" on a 2.18" taller tire?

Miss Rita
10-11-2012, 01:10 PM
If one tire is 2" taller than another, the radius is 1" greater, you would need 1" extra clearance above the tire, and the trailer will ride 1" higher.

O2BESOHUGE
10-11-2012, 03:04 PM
I GOT MINE HERE...THEY CAME MOUNTED WITH CENTER CAPS AND LUG NUTS READY TO BE PUT ON THE TRAILER. I WENT WITH AN INCH BIGGER RIM AND THEY FIT FINE.

http://www.sturdybuiltonline.com/Trailer-Tires-Mounted-on-Wheels_c_3.html

THEY SURE ARE PURTY!!

memphis23
10-11-2012, 04:10 PM
OH2B: We have the exact same trailer.

What a beauty of a boat and yes those wheels look great!!

If you don't mind me asking how much did you pay?

O2BESOHUGE
10-11-2012, 04:35 PM
I Watched The Web Site And Got Them On Sale...i Think I Paid About $125 Per Wheel And Tire Already Mounted And Shipped To My Door.

By The Time I Went To A Local Shop And Bought Everything There And Had It Mounted And Balanced. It Would Have Been More Than I Spent Online

O2BESOHUGE
10-11-2012, 04:38 PM
I Did The Exact Same Thing But Went Back With Stock Rim And Tire Size On My 89...i Just Liked The Way They Looked And They Were Close To The Newer Mastercraft Rims In Looks But No Where Near The Price!

memphis23
10-11-2012, 04:59 PM
So you are back on 205/75/14 in this picture?

memphis23
10-11-2012, 05:00 PM
I Did The Exact Same Thing But Went Back With Stock Rim And Tire Size On My 89...i Just Liked The Way They Looked And They Were Close To The Newer Mastercraft Rims In Looks But No Where Near The Price!

So You are on 205/75/14 in this picture?

O2BESOHUGE
10-11-2012, 05:02 PM
Yeah On The 89 I Was...went To The 15's On The 1991 Trailer

memphis23
10-11-2012, 05:04 PM
http://www.mastercraft.com/teamtalk/attachment.php?attachmentid=85268&stc=1&d=1349982277

Is this your new boat or do you have both of these?

O2BESOHUGE
10-11-2012, 05:14 PM
I Sold The 89 Locally And Bought The 1991 From A Member Here...

memphis23
10-11-2012, 05:18 PM
http://www.mastercraft.com/teamtalk/attachment.php?attachmentid=85268&stc=1&d=1349982277

Is this your new boat or do you have both of these?

Yes I am going to measure tonight to make absolutely sure that they will fit but I think I am going with the 225/75/15 ThatMr. Has told me about some QR trailer tires

memphis23
10-11-2012, 05:22 PM
I Sold The 89 Locally And Bought The 1991 From A Member Here...


What are the noticeable differences between the two boats. I have an 88 looks just like your other one.

Ride, space, handling??

O2BESOHUGE
10-12-2012, 09:46 AM
To Me...the Main Difference Was The 1991 Feels Like It "floats" Or "sits" Higher In The Water Than My 89 Did. The 1991 Was A Little Wider, A Little Smoother Driving And Steering - But That Just May Be The Boat And How It Was Maintained Fromthe Previous Owner.

Its Kind Of Like Having An 89 Corvette And Then Getting The 1991 Model. They Are Still Vettes, Same Type Performance, Just One May Be A Tad Different. Im Trying To Use Them As Stepping Stones To Eventually Get Up To A Pro Star 197. Ill Buy One And Take Care Of It And Sell It A Few Years Later.

My Only Drawback Is...what Can I Do With My Skill Level At Skiing, Wakeboarding, Etc...better With A Newer Boat Than What I Have? Basically Nothing. So Unles I Have A Huge Winfall In Some Funds Coming In - It Looks Like Im Going To Keep My 1991 For A While Longer! It Does All We Need It To Do. I Just Like The Hull On The Newer 197's

....maybe Someday! A Fella Can Dream!! Haa!

memphis23
10-18-2012, 05:29 PM
After further research I have discovered that there are 0, C+ load, trailer tires made in the good old USA. All China, and Thia land, Korea, Vietnam.

thatsmrmastercraft
10-18-2012, 09:21 PM
Making tires is a very emissions unfriendly process and it is very difficult and expensive to keep on the good side of the EPA.

memphis23
10-18-2012, 10:01 PM
yes indeed it is but it is a shame that what we import is not held to the same standards