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wheels and tyres topic -think twice before you buy-

Posted: Thu Sep 24, 2009 2:07 pm
by karlos
Just for the sake of it I thought i'd say -because you all seem so keen on specification-

Have notice lots of threads relating to this subject, To mention pressures and tyre choice ,I will add another element, wheel size.

I have notice people talking about ride comfort at certain speeds my bongo seems good at all, all speeds - suspension/chassi roll a bit much but a stiffer setup would make it less of a cruiser.

I run standard wheels.

Do not be tempted to go for the nice looking big wheels with low profiles or shorter height wall. I dont care what bob at the tyre centre say's it's not the way forward. Yes it will slightly extend the length of the gearing and give a slightly higher top speed (probably slightly improve fuel economy on longer distance if it keeps the revs down in relation to speed) if the overall diameter is increased you will also lose some torque.

A bigger wall tyre/standard wheel - the tyre actually is part of the suspension, it helps soak up the knocks and flex to give grip round the corners.

Low profiles like on bmw's, speed up/sharpen the feel - make the ride harder, actually give less grip round corners as they dont bend much - the suspension has to be designed to compensate.

Doesnt matter much at the legal speed limit, but if you want comfort it will make a difference, and not so good for snow dirt etc.

Strange how they got it right years ago with big ugly tyres. That's not to say big rims and low profiles "bling" are not suitable for the cars that they come on as standard.

But people tend to go/upgrade from 15" to 16"or 17" etc. use a thinner walled tyre to keep the rolling diameter similar to standard as thats what they are told- plus it looks good - push a car hard and it will understeer or oversteer much more easy at high speed like that or in the wet etc.

Stick with standard sizes it's the way forward.
(unless you dont mind compensating comfort for style)

Wider wheels have pro's and cons to

Re: wheels and tyres topic -think twice before you buy-

Posted: Thu Sep 24, 2009 2:42 pm
by francophile1947
Well that's a nice simplistic post #-o It also overlooks the fact that manufacturers often fit the cheapest options they can get away with, which explains why more upmarket versions of the same vehicle usually have different wheels and tyres to the basic model, without any alteration to the suspension.
karlos wrote:Yes it will slightly extend the length of the gearing and give a slightly higher top speed (probably slightly improve fuel economy on longer distance if it keeps the revs down in relation to speed)
No it won't, unless you fit oversize tyres :roll:
I agree that ride comfort may well be affected with very low profile tyres (as in the BMWs), but I doubt you'd notice much difference between a 65 and a 55 profile and the handling is definitely improved - you don't get anywhere near as sea sick from body roll :lol:

Re: wheels and tyres topic -think twice before you buy-

Posted: Thu Sep 24, 2009 3:58 pm
by mikeonb4c
karlos wrote:Just for the sake of it I thought i'd say -because you all seem so keen on specification-

Have notice lots of threads relating to this subject, To mention pressures and tyre choice ,I will add another element, wheel size.

I have notice people talking about ride comfort at certain speeds my bongo seems good at all, all speeds - suspension/chassi roll a bit much but a stiffer setup would make it less of a cruiser.

I run standard wheels.

Do not be tempted to go for the nice looking big wheels with low profiles or shorter height wall. I dont care what bob at the tyre centre say's it's not the way forward. Yes it will slightly extend the length of the gearing and give a slightly higher top speed (probably slightly improve fuel economy on longer distance if it keeps the revs down in relation to speed) if the overall diameter is increased you will also lose some torque.

A bigger wall tyre/standard wheel - the tyre actually is part of the suspension, it helps soak up the knocks and flex to give grip round the corners.

Low profiles like on bmw's, speed up/sharpen the feel - make the ride harder, actually give less grip round corners as they dont bend much - the suspension has to be designed to compensate.

Doesnt matter much at the legal speed limit, but if you want comfort it will make a difference, and not so good for snow dirt etc.

Strange how they got it right years ago with big ugly tyres. That's not to say big rims and low profiles "bling" are not suitable for the cars that they come on as standard.

But people tend to go/upgrade from 15" to 16"or 17" etc. use a thinner walled tyre to keep the rolling diameter similar to standard as thats what they are told- plus it looks good - push a car hard and it will understeer or oversteer much more easy at high speed like that or in the wet etc.

Stick with standard sizes it's the way forward.
(unless you dont mind compensating comfort for style)

Wider wheels have pro's and cons to
Lots of interesting stuff in this post I think. I've got 15" steels and Kumhos and I now have (fitted) 17" wheels and Pirelli P7s 215/55/17 (cheap off ebay but a superb tyre - I'd never afford them as new tyres). The ride IS a bit harsher, but in all other respects I find it much better. Overall, I find my Bongo doesn't like poor road surfaces, whether on 15" or 17" tyres, and it is this that is the crucial factor. So I might as well be rattled a bit more than a bit - its all annoying. Also, being heavily loaded makes the situation worse.

So really, I long to be on a nice road surface, which is usually the case on the A roads and motorways I bought the Bongo to travel on. I get much crisper handling with the 17" wheels, (I've gone for 55 depth to reduce the harshness and may try 60s next time - as you say Karlos, fat tyres help) and the ride is smooth and quiet.

One thing I never realised until I got all 4 wheels balanced on the Bongo. Not only does this get rid of e.g. steering wobble at 65mph (that well known problem) but it prevents the unpleasant long rebound you can get at any speed above 20mph or so and when you go over potholes etc. (my guess is an unbalanced wheel, esp. with high mass, takes longer to damp the eccentric movement out of) so that - in effect - the ride is less harsh. This is as relevant for the rear wheels as for the front ones. And if you cast your mind back, it was a characterisitc site to see the wheels of old cars like the Wolsey 15/50, with its bit fat tyres/wheels running on poorly working shockers, quivering like jellies as the car tramped down urban streets.

Image

....ah....Sentimental Journeys 8)

Re: wheels and tyres topic -think twice before you buy-

Posted: Thu Sep 24, 2009 5:28 pm
by Colin H F
might I ask what you intend doing with your old 15" steels as I am looking for one to replace my skinny? Colin

Re: wheels and tyres topic -think twice before you buy-

Posted: Thu Sep 24, 2009 6:01 pm
by mikeonb4c
newbie wrote:might I ask what you intend doing with your old 15" steels as I am looking for one to replace my skinny? Colin
Ah :oops:

I keep them (with loads of tread on the tyres) so that when the P7s wear out and I can't afford to replce them, I can put them back on while I save up for replacements for the 17" ones.

I've seen sets of steels coming up v. cheap on ebay and I thik everytime that it would be worth someone bidding for them either to keep them as a reserve set for themselves of to keep one as a spare then flog the others on. Might be worth watching and pincing, or contacting a local Bongo garage, as they sometimes have spares (Manchester Campers sold me my spare for £10 with a good tyre as they had loads of unwanted ones out back) 8)

Re: wheels and tyres topic -think twice before you buy-

Posted: Thu Sep 24, 2009 7:35 pm
by karlos
Well francop,

I'm sorry chap. I did put in my post if you allter the rolling diameter, that is not the wheel size but the out side diameter of the tyre,

as I'm obviously simple - mark a line on the tyre roll it when the line touches the ground for the second time measure thats distance -

If you fit 15 wheels with a 3 to 4" wall height which is about normal,

if you fit 16 or 17" you would have to have a slimmer wall or even low profile to keep the rolling diameter close to original - usually effects speedo calibration -

nothing to do with over sized tyres if you were to fit 16" or 17" wheels with the same height/standard road tyre wall they would increase the rolling diameter.

And I dont want to rub people up the wrong way about what I do, but I know for a fact the difference between low profiles, big wheels and larger tyre walls on smaller wheels. ( corner effect isnt really that relevant at these bongo speeds - but some one mentioned ride comfort in a thread and bigger wheels that run less tall walls will be a harder ride if only marginal) and as I said will grip less in the wet and snow mainly noticable when driving quick in the corners.

If you dont believe take out a caterham or westfield with the two different combinations on - You dont need to cause I have -

One other advantage of skinny wall tyres that they are less likely to peel off the rims in extreme cornering.

The comment about basic vechicles - most sxi,sri,gsi,gti,etc. they do come with different wheels, they do have different supension, brakes usually too. They might even have different ride height, slightly more tilt or less to the front, traction control etc.

I bet the fastest cars m3, porsche 911'turbos etc run a bit more camber too than there lower spec models.

Most cheaper cars may come with 13" or 14" steel wheels and an option or upgrade to alloys these alloys are 95% of the time same size as the steel wheels they replace maybe a bit wider and run very similar wall height tyres(not altering original spec.

Look at micra's saxo vtrs etc. original alloy wheels, chunky tyres. Top spec cars are set up for big wheels and low profiles.

Any one who argues this disagrees with all racing practice where people spend silly money to gain half a second, f1 and racing is where the technology develops for improvements to road vechicles, rubber, brakes,cooling,composites different metals.

I'm no bongo expert but I know what makes a vehicle handle.

Sorry you guy's with bigger wheels -they do look good - just dont go for ultra slim look low profiles.

Well I supose it's ok if you dont drive like an idiot or in the snow and mud and dont mind a bit more nimble steering and a slightly harsher ride on more bumpy roads. I supose on the bongo suspension with a lot of travel it soaks alot up anyway.

Any one got a spare gearbox xxxx

Re: wheels and tyres topic -think twice before you buy-

Posted: Thu Sep 24, 2009 7:48 pm
by karlos
I was really refurring to low profiles or short walled tyres, 10mm or so wont make that much difference on a van.

I went from 17" low profiles to 13" with about a 4.5" wall yokohamma 48r's on my last car - road legal race car -

The guy I bought it off put the big wheels on cause they looked nice, I put it back to spec/setup of manufacture - It went from a rocket with no high speed grip to a rocket with capable of high g inturnal organ damaging cornering speeds with better all round traction(thats not an exageration)

Now you show me a race car other than a bmw saloon car with big wheels and skinny walls, and I will show you a thousand with small wheels diameter wheels and chunky tyres. Although they do not weigh 2 tonne.

Re: wheels and tyres topic -think twice before you buy-

Posted: Thu Sep 24, 2009 8:06 pm
by hembramacho
newbie wrote:might I ask what you intend doing with your old 15" steels as I am looking for one to replace my skinny? Colin
I've got a spare 15" steel (no tyre) going if you want to make me an offer!

Andrew

Re: wheels and tyres topic -think twice before you buy-

Posted: Thu Sep 24, 2009 8:15 pm
by dandywarhol
karlos wrote:Well francop,

I'm sorry chap. I did put in my post if you allter the rolling diameter, that is not the wheel size but the out side diameter of the tyre,

as I'm obviously simple - mark a line on the tyre roll it when the line touches the ground for the second time measure thats distance -

If you fit 15 wheels with a 3 to 4" wall height which is about normal,

if you fit 16 or 17" you would have to have a slimmer wall or even low profile to keep the rolling diameter close to original - usually effects speedo calibration -

nothing to do with over sized tyres if you were to fit 16" or 17" wheels with the same height/standard road tyre wall they would increase the rolling diameter.

And I dont want to rub people up the wrong way about what I do, but I know for a fact the difference between low profiles, big wheels and larger tyre walls on smaller wheels. ( corner effect isnt really that relevant at these bongo speeds - but some one mentioned ride comfort in a thread and bigger wheels that run less tall walls will be a harder ride if only marginal) and as I said will grip less in the wet and snow mainly noticable when driving quick in the corners.

If you dont believe take out a caterham or westfield with the two different combinations on - You dont need to cause I have -

One other advantage of skinny wall tyres that they are less likely to peel off the rims in extreme cornering.

The comment about basic vechicles - most sxi,sri,gsi,gti,etc. they do come with different wheels, they do have different supension, brakes usually too. They might even have different ride height, slightly more tilt or less to the front, traction control etc.

I bet the fastest cars m3, porsche 911'turbos etc run a bit more camber too than there lower spec models.

Most cheaper cars may come with 13" or 14" steel wheels and an option or upgrade to alloys these alloys are 95% of the time same size as the steel wheels they replace maybe a bit wider and run very similar wall height tyres(not altering original spec.

Look at micra's saxo vtrs etc. original alloy wheels, chunky tyres. Top spec cars are set up for big wheels and low profiles.

Any one who argues this disagrees with all racing practice where people spend silly money to gain half a second, f1 and racing is where the technology develops for improvements to road vechicles, rubber, brakes,cooling,composites different metals.

I'm no bongo expert but I know what makes a vehicle handle.

Sorry you guy's with bigger wheels -they do look good - just dont go for ultra slim look low profiles.

Well I supose it's ok if you dont drive like an idiot or in the snow and mud and dont mind a bit more nimble steering and a slightly harsher ride on more bumpy roads. I supose on the bongo suspension with a lot of travel it soaks alot up anyway.

Any one got a spare gearbox xxxx
Well said =D> =D>

I've driven both big wheeled low profile tyre and standard setup and personally prefer the ride quality of the standard setup. The Bongo does not handle well BUT does road hold and ride well as standard - it's all a compromise.............

Re: wheels and tyres topic -think twice before you buy-

Posted: Thu Sep 24, 2009 8:17 pm
by francophile1947
karlos wrote:Well francop,

I'm sorry chap. I did put in my post if you allter the rolling diameter, that is not the wheel size but the out side diameter of the tyre,
What you actually said was "if the overall diameter is increased you will also lose some torque." - no mention of a different diameter when referring to the increased gearing.
I assume you are referring to the rolling circumference of the tyre - the diameter doesn't roll.
I fail to see what race cars have got to do with a slowish 2 tonne brick. No modifications could ever make it perform like a Caterham, or a racing BMW, around a track and it will also be a lot less susceptible to the bumps than they are.
All the models you refer to appear to be the sporting versions of road cars whereas I was referring to the "posher" models i.e. better trim etc - same car, just tarted up a bit.

Re: wheels and tyres topic -think twice before you buy-

Posted: Thu Sep 24, 2009 8:24 pm
by dandywarhol
francophile1947 wrote:
karlos wrote:Well francop,

I'm sorry chap. I did put in my post if you allter the rolling diameter, that is not the wheel size but the out side diameter of the tyre,
What you actually said was "if the overall diameter is increased you will also lose some torque." - no mention of a different diameter when referring to the increased gearing.
I assume you are referring to the rolling circumference of the tyre - the diameter doesn't roll.
I fail to see what race cars have got to do with a slowish 2 tonne brick. No modifications could ever make it perform like a Caterham, or a racing BMW, around a track and it will also be a lot less susceptible to the bumps than they are.
All the models you refer to appear to be the sporting versions of road cars whereas I was referring to the "posher" models i.e. better trim etc - same car, just tarted up a bit.
Karlos is right with that info John, increased the diameter of the wheel/tyre and you'll automatically increase the rolling circumference, thereby decreasing the torque by raising the gearing. Pi x R squared and all that...........................

Re: wheels and tyres topic -think twice before you buy-

Posted: Thu Sep 24, 2009 10:33 pm
by Dave and sally
I think that some people neglect to notice the load rating of the actual alloys and also the tyres (especially the low profile tyres )
Its not safe to run incorrect tyres ,Bongo's are heavy then you load them to go camping

Cant see the point in bling wheels on a bongo whats the point? just buy a subaru or some other chav motor ?

i do own a bongo (well freda) as we do like to camp and i have 4 kids i also think its the most ugly vehicle ive ever owned not to mension its stupid name :roll: but too me its a good tool and great car for family of six

Re: wheels and tyres topic -think twice before you buy-

Posted: Fri Sep 25, 2009 12:41 am
by Alison01326
Dave and sally wrote:I think that some people neglect to notice the load rating of the actual alloys and also the tyres (especially the low profile tyres )
Its not safe to run incorrect tyres ,Bongo's are heavy then you load them to go camping

Cant see the point in bling wheels on a bongo whats the point? just buy a subaru or some other chav motor ?

i do own a bongo (well freda) as we do like to camp and i have 4 kids i also think its the most ugly vehicle ive ever owned not to mension its stupid name :roll: but too me its a good tool and great car for family of six
Ah, good. I am still on the Bongo forum :wink:

Re: wheels and tyres topic -think twice before you buy-

Posted: Fri Sep 25, 2009 8:59 am
by karlos
I'm not for or against anything,

I actually like the look of the bongo, and can see why people want to fit big wheels will slim looking tyres.

I have always had a van of sorts since I started driving - I like the look of the merc vito and I think the bongo from certain angles resembles it. The merc vito from new is a quick van but olders ones are seem not so good.

The bongo is much more practical - the guy's laughed at me at the gym when I said you can get body kit etc for them.

Because of the enviroment I will use my one in, I will tart it up in a discreet fashion.

I do understand how ever a lowered van or big wheels etc. all have a knock on effect. I've had a car where you actually sit 4 and 1/2" off the ground - not the most comfortable, It all depends what you lose in return for some thing else. The same car had the big wheels that I put back to original spec.

I will keep standard wheels as to maintain design perameter's (good on long haul, slightly bumpy roads, grass,snow,dry wet)

I will fit a basic body kit to give the impression it's slightly lower to the ground.

I will not lower as to keep the tow hitch at a normal height and drive shafts at standard operating angles. -It would be nice (for cosmetic reasons)to put bigger wheels on, lower it using shorter stiff springs, then you should really adjust the dampers too, but if I do that it just wont be as versatile.

I may look at moving the front numberplate and improving cooling to those rad's for towing if I here of many more head gaskets going on this forum. -Although with out taking a mould of the front bumper and making a new one it will be difficult to make it look half sharp.

I need the bongo to perform as -people carrier,smart looking trailer towing,tool carrying work/collections van and some where to stop the night in if the multi purpose car trailer/workshop/camper is full .



I personally think that if this motor "ranger lump?" is prone to headgaskets going? maybe we should all be running something like stack dashor a couple extra gauges, my race car can scroll its menu, water temp in deg's, oil pressure,oil temp,and a whole lot of other thing's. (expensive though)

You get to know the normal running perameters say, town trip, motor way, towing. If the bongo starts operating out side the norm acting it's time to pull over or reduce speed before serious harm is done. I personally check my coolant level and oil regular. Obviously with addition data it is possible to know if the water pump or oil pump is not work which will can kill a motor way before that happens.

I know all the running perameters of my car (stack dash). 18psi oil pressure at tick over (less alarm light plus upper limit),water temp 80/85 deg when running hard (max 95/100 then alarm light) oil temp 80 -90 deg when running hard (120 deg max) high pressure fuel 3.5bar,etc..ect...

I think water temp, oil temp maybe oil pressure too and volts is good on a road car that is slightly more prone to problems or is not standard. I noticed the reliable mgtf has, I'm suprised to see some new models dont have any in front of the driver,are cars that reliabe now? I know people who never check oil or water!

I suspect I might fit a couple of extra gauges (oil and water) in my blanking plate under my stereo just to give me a bit of peace of mind.



Francop - I might get some of my terminiology mixed up when typing this poo out. I do get the results and can put theory into practice. (people mention ride comfort,I respond with my take)

I know most road drivers are not into all this pant's. When you start getting specific it all becomes relevant. Each to there own!

I'm a bit of a engineering geek I supose.

Re: wheels and tyres topic -think twice before you buy-

Posted: Fri Sep 25, 2009 9:08 am
by dandywarhol
I think more gauges cause too many distractions - minimalist is best for me. Look in the "search" facility and theres hundreds of posts about Haydn alarms and Mason alarms - they're all you really need to pre warn of impending doom. An audible warning still keeps your eyes on the road :wink:

I've had my Bongo for 3 1/2 years now. I've properly maintained the cooling system since day 1, fitted a Mason alarm and apart from a swollen hose (oh er, missus) I've had no problems - just enjoyment from a vehicle which has taken me around most of Europe =D>