The "Tyreselecta" Thread

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young_dubya

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Ive been wading through though internet the last couple of nights trying to establish what tyres to run on my bus based on

A) how cool they will look (Sidewall heights) Obviously THEE most important factor :lol:
B) The load rating- Important to me as my bus is my daily so i want something that at least covers the max weight the bus can carry.

Just thought id share some useful links and calculations (please bear with me as ive tryed to make it as simple as possible as ive confused myself a few times :lol: ) ive been using to establish the above.

First up is the continental sites tyre Search
http://www.conti-tyrefinder.co.uk/index.php" onclick="window.open(this.href);return false;

I basically had a look through the stance thread on here (http://forum.earlybay.com/viewtopic.php?f=4&t=7365" onclick="window.open(this.href);return false;) for a front set of tyres i thought i liked and entered the details into here to get the load rating of said tyre. It doesnt cover all sizes of tyre but will give you a good idea.

Then i used this site to find what the load ratings meant
http://www.tyresave.co.uk/tyreload.html" onclick="window.open(this.href);return false;

This helped me find tyres that will cover at LEAST the load that the front beam on my bus will be rated at.

Now for the tricky bit (and most likely the bit ill get wrong :lol: ) the carol vorderman bit

Sidewall depth/height.
Side wall height/depth can be calculated quite easily by using the tyre markings

For example take a 165/65 R15 81V tyre. The 165/65 is the part you need to establish your sidewall height.

165 is the width of the tyre and the 65 means the sidewall of the tyre is 65% of the tyres total width.

SO! 165 divided by 100 gives you 1% of the tyre width which in this case is 1.65mm

So the 1.65mm x 65= 107.25mm

Therefore! The sidewall depth on a 165/65 R15 is 107.25mm!!

Wheel sizes Inches to mm
If anybody has been viewing the "Slammed earlies" thread has seen the measure ments then this (with the above) Is used to establish overall wheel/tyre height. I have to say that there are probably easier ways but thia is the one i used :lol: :lol: .

Basically 1" is 25.4mm

So your 15" alloy wheel in mm is calculated 15x 25.4= 381mm

If you double your sidewall thickness (if you intend to run a tyre all the way around your rim :lol: ) and add it to this you will achieve your wheel/tyre height fromt he floor for example

A 15" Radar wheel running on a 165/65 R15 81V tyre will be a total height of
107.25 x 2 + 381 = 595.5mm or 60cm (ish).
(Sidewall depth x2) + wheel diameter = wheel tyre height.


I know with some folk im teaching my granny to suck eggs but i hope this thread is useful to some people. Some folk get tyres others dont. Im not tyre expert just hadnt seen anything like this on here and thought it may come in handy. I hold no responsability for yours or anybody elses cock ups from info on here :lol:

If anybody can put me straight on anything or knows a simpler way (i know it will be done with grace and etiquet unlike other forums :lol: ) Please let me know and ill try my best to ammend the thread.

Cheers dudes! May your searchs be fruitful and your breakdowns easy to fix! :mrgreen:

Ash

Other useful info has been added further along in the thread such as:

Baywindow Overall weights and axle weights
Speedo/new tyre calculations
Gearbox ratios
Info on various tyres load ratings


Theres also some info about a dude who can whitewall them for you but i cant for the life of me remember his name??? :p :lol:
 
Hi!

I think the problem most folk have is that there smart car tyre which looks so cool on a slammed bus are not suitable for this purpose as the load rating does not match the weight of the bus - AFAIK, this is why the stock tyres have a commercial rating - because of the weight. Surely a issue of legality here? Running tyres unsuitable for the vehicle they are on? :| You know what insurance companys are like for worming out of a payout? And i'm sure the police would take a dim view.....your policy would be null and void? Right can of worms this! :sick0010:

I dont think you can get properly load index rated commercial tyres in these slammed and low profile sizes - unless someone knows otherwise, as my bus is waiting for a narrowed K and L pin beam rolling on anthracite speedmasters running commercial low pro tyres - so until then, my family will be riding safe and high on stock commercials correctly rated thank you very much!

Cheers!

Alistair
 
good thread.

with regard to the load rating, always a hot topic, the way I see it is like this.

say you fit a 175/50 R15 75H front and 185/65 R15 88H rear

the front axle has a load rating of 2x387kg = 774kg
and the rear axle has a load rating of 2x560kg = 1120kg

so a max load rating of 1894kg
 
also found this

http://www.type2.com/library/tires/t2tirefq.htm" onclick="window.open(this.href);return false;

Summary of Tire Requirements for a Type 2:

This is a conservative outline of how to choose the best tires for your Type 2 based on factory recommendations. Running tires that are insufficiently load rated, for a passenger car, or too wide (especially on a heavier Type 2 camper) can lead to problems such as: tread separation and blowouts, poor handling, and premature steering component wear. Wider tires such as 205s will fit under the wheel well, but might scrape the bodywork in turns and will be more difficult to steer from a standstill.

SIZE: 185R14 (195 is also acceptible providing they meet the other load and sidewall requirements)
LOAD RANGE: "C" or "D" Light Truck (LT) tires.
MAXIMUM LOAD RATING: 1500-1700 lbs +
MAXIMUM INFLATION PRESSURE: 50-65psi.
SIDEWALL: Must have reinforced sidewall (i.e. more than the standard one ply sidewall found on a passenger car tire). Preferably 4 ply sidewall--this is the critical factor for improved handling.
Other considerations:

ALL SEASON: M+S (mud and snow) rated, all season (depends on your individual driving conditions/climate/local laws)
TREAD: Preferably aggressive
An Example of an Ideal Tire Meeting All the Above Criteria:

Yokohama LT195/75/R14
Tire rack #37047
1750 lb/D load range, 8 ply, LT tires


The Yoko Y370 LT 195/75 R 14 M&S are D load rated with 6 Steel belts and 2 Nylon. The sidewalls have 2 steel and 2 nylon.

HIGHWAY ALL SEASON
LT195/75R14 YO Y370 D 58.00(must be special ordered)
 
AxlFoley said:
good thread.

with regard to the load rating, always a hot topic, the way I see it is like this.

say you fit a 175/50 R15 75H front and 185/65 R15 88H rear

the front axle has a load rating of 2x387kg = 774kg
and the rear axle has a load rating of 2x560kg = 1120kg

so a max load rating of 1894kg

I think that may be illegal as you havent covered the maximum weight of your axles. Im going to go for

165/65 R15 81H on the front my front axle i will then downgrade to 900kg (as its a splitty beam) the 81s just cover the load rating. Im never going to have my van over that weight and on the rear ive found some tyres that are a 98 in the profile i want. Ill stick some more info up when ive sorted it :mrgreen:
 
ok edited my post cos I was lazy and decided to search.....

pg79.jpg


so it looks like 500kg loading on the front and 600kg loading on the rears [that's per tyre and for a camper]

which equates to a 84 front load rating and a 90 rear as a 'to the specs' guide........
 
I use this site for with the link below to get an idea
http://www.camskill.co.uk/products.php?plid=m53b0s0p0" onclick="window.open(this.href);return false;
it's because the way the sizes are laid out is easier to choose

this link I have used before to see visually!!
http://www.kouki.co.uk/utilities/visual-tyre-size-calculator" onclick="window.open(this.href);return false;

:D
a std tyre is 65cm approx diameter iirc

all these tyres meet the loading for front
185/60 r15 88H XL http://www.camskill.co.uk/products.php?plid=m53b0s410p12881 60.3cm dia
185/55 r15 86V XL http://www.camskill.co.uk/products.php?plid=m53b0s287p3603 58.45cm dia NOTE this was the only one that was on that site in this size , that was above an 82load
175/65 r15 84H http://www.camskill.co.uk/products.php?plid=m53b0s416p52171 60.8dia NOTE this size is a bit sketchy as on the load limit and isn't an XL ie more plys, but may be suitable for thinner front alloys?
195/45 r15 82V http://www.camskill.co.uk/products.php?plid=m53b0s92p3641 55cm dia NOTE perhaps this is a slam tyre? the load is on the cusp BUT is a XL tyre, and maybe too wide for 5" rims?
195/50 r15 86V XL http://www.camskill.co.uk/products.php?plid=m53b0s99p8977 dia57cm NOTE again struggled to find a tyre that was upto the load for the fronts, but is quite low but maybe too wide for 5" wheels?


14" fronts
175/65 r14 86T xl[ url]http://www.camskill.co.uk/products.php?plid=m4b0s393p50355[/url] dia58cm
:msn4:

also good

http://www.alloywheels.com/tyrecalc.asp" onclick="window.open(this.href);return false;

has a few different calculators in there inc rim width - so a 185 55 r15 will fit 5"-6.5" rim
 
Also if anybodys got any pictures of thier tyres. :mrgreen: It all helps make it easier :mrgreen:

Thats a wicked gizmo!!! :mrgreen: :mrgreen:

Im not trying to say yay or nay to smart car tyres or anything. Its up to the owner of the vehicle (but at 345kg per wheel not for me ta :lol: )

Think a list is a good idea ad especially with photos.

Ash.
 
I would just like to add what ever tyre you choose skinny, fat, wide, thin, smart car or commercial.............


They can all be striped..............http://www.mrwhitewalls.com

:party0009: :party0009: :party0009: :party0009: :party0009: :party0009: :party0009: :party0009: :party0009:
 
Hey top post! - had a rough idea that it was rated on the percentage sidewall size to overall diameter but that explains it well 8)

Only thing that would confuse me - is the speedo being affected (not that mines all that accurate!) - if you lower the overall diameter it'll through it off and read too high? Is the idea to go for a bigger wheel and smaller profile tyre to keep the same overall diameter or is that kind of second to the stance/style of the overall combination (or can you adjust the speedo to get around it?)
 
US based, but http://www.tirerack.com" onclick="window.open(this.href);return false; has lots of specs listed. An example: http://www.tirerack.com/tires/Spec.jsp?make=Continental&model=ContiProContact&vehicleSearch=false&fromCompare1=yes&partnum=965HR5CPC&tirePageLocQty=%26partnum%3D965HR5CPC" onclick="window.open(this.href);return false;
 
lard said:
Hey top post! - had a rough idea that it was rated on the percentage sidewall size to overall diameter but that explains it well 8)

Only thing that would confuse me - is the speedo being affected (not that mines all that accurate!) - if you lower the overall diameter it'll through it off and read too high? Is the idea to go for a bigger wheel and smaller profile tyre to keep the same overall diameter or is that kind of second to the stance/style of the overall combination (or can you adjust the speedo to get around it?)


the rears you do want to try and keep somewhere close so the 'box and ultimately the cooling fan are at similar revs to std[affected by speed v revs for that speed], the front as there's less room for lowering, the tyres like a 185/55 r 15 will be quite small but not smart car rubber band type. ie running a 185/55 is actually nearly 2" off the normal diameter!
Not sure how much it is to recalibrate your speedo [or if anyone ever bothers?] but speedycables can do it from some measurements.
I'll try and get a approx price and post back so it's all in one thread?
 
thats a good point, but I was running standard tyres on my van when i Bought it and my spedo was 20mph out at 55mph lol

I use my sat nav now :p
 
I have some calculations also for how far out your speedo is from your tyre size too ill fathum those again and stick them up.

My bug is about 5mph to high at 30mph to 10mph @100mph Or h on my 100mph bug clocks :lol:

Quality link dude!!
http://www.tirerack.com/tires/Spec.jsp?make=Continental&model=ContiProContact&vehicleSearch=false&fromCompare1=yes&partnum=965HR5CPC&tirePageLocQty=%26partnum%3D965HR5CPC" onclick="window.open(this.href);return false;
 
This may be useful if you know your gearbox ratios:
http://www.boosttown.com/gearbox_differential/speed_calculator.php" onclick="window.open(this.href);return false;


And this may help as well ;)

Code Engine 1st 2nd 3rd 4th Rev. Final Years
CA 1600 3.80 2.06 1.26 0.82 3.61 5.375 68-71
CB 1600 3.80 2.06 1.26 0.82 3.61 5.857 68-71
CC 1600 3.80 2.06 1.26 0.82 3.61 5.375 68-71
CD 1600 3.80 2.06 1.26 0.82 3.61 5.857 68-71
CE 1600 3.80 2.06 1.26 0.82 3.80 5.428 72-75
CF 1600 3.80 2.06 1.26 0.82 3.80 5.857 72-75
CG 1600 3.80 2.06 1.26 0.82 3.80 5.375 72-75
CH 1600 3.80 2.06 1.26 0.82 3.80 5.857 72-75
CK 1700 3.80 2.06 1.26 0.82 3.80 5.375 72-73
CL 1700 3.80 2.06 1.26 0.82 3.80 5.375 72-75
CM 1800 3.80 2.06 1.26 0.89 3.80 4.857 74-75
CN 1800 3.80 2.06 1.26 0.89 3.80 4.857 72-75
CP 2000 3.78 2.06 1.26 0.88 3.28 4.571 76-79
CT 2000 3.78 2.06 1.26 0.88 3.28 4.571 76-79
CU 1600 3.78 2.06 1.26 0.82 3.28 5.428 76-79
CV 1600 3.78 2.06 1.26 0.82 3.28 5.428 76-79
CW 1600 3.78 2.06 1.26 0.82 3.28 5.857 76-79
CX 1600 3.78 2.06 1.26 0.82 3.28 5.857 76-79
 
Right!! Ill add this to the OP along with your awesome links! :mrgreen:

Speedo diffrence with new tyres.
To find the speed diffrence of your new lower/higher profile tyres you need to know how much distance 1 rev of your wheel covers(imagine cutting your tyre and rolling it out on the floor) for this you need the circumfrence of the tyre you need to do the calculations at the top which find the overall diameter of wheel/tyre (and a scientific calulator).

So for this:

d= Diameter of the tyre
∏= 3.14 (i think! :lol: ive not used pie since school so correct me if im wrong)

∏ x d= Circumference of wheel

So take the 165/65 R15 we mentioned before and its diameter of roughly 60cm

3.14 x 60 = 188.4cm or 1.88m

Now you know the distance your tyre travels in 1 revolution you can calculate how many revs per mile! YE SEE! IM GETTING THERE :lol:

1 mile = 1 609.344 metres or for this purpose 1609.3m
1Km = 1000m

so to find how many revs per mile you need to divide 1mile by the circumfrence of the wheel

So again for the 165/65 R15 its:

1609.3
-------------- = Approx 856rpM (revs per Mile)
1.88

Now this is where i confuse my self :lol:

A stock 7.00 x 14 tire is comparable to an 195/75 R14 which is 668mm diameter and 210cm (2.1m) around.

So in 1 mile the stock 195/75 R14 revolves 766.3 rpM


So in 30miles our 165/65 R15 will revolve 25680 times
And the stock 195/75 R14 will revolve 22989 times

Using this you can calculate how fast the speedo says your are going if you had your original wheels.

So! (getting VERY confused now! :lol:)

You need to find out what road speed your standard wheel would be doing at the speed of your new wheel.

So simply divide the new tyres 25680 by the stock wheels 766.3rpM

25680
--------------- = 33.5mph!!! (Oh yes!! Sounds feasable so will call this theory NAILED! :lol: )
766.3

So you will need to calculate for all the common road speeds. :mrgreen:

I have probably ROYALLY screwed this up so do let me know if you see a problem.

Either this or find one of those speed reading guilty makers and drive through it until you hit the correct speeds and typex yer speedo :lol: :lol: :lol:
 

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