Bigger Wheels that are lighter than Std.

MightyBoy tech questions and answers.
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me217
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2 wheels? :-o and what speed do you hit the corners to do this. :twisted:

me217
me217

1985 suzuki mighty boy : mods, f8b
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ToranaGuy
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me217 wrote:2 wheels? :-o and what speed do you hit the corners to do this. :twisted:

me217
To be honest i dunno, never look at the speedo when i'm cornoring that fast, i've also seen my g/f get the mb up onto two wheels taking cornors, when i was following in my Ford. :lol:

Funnier yet, i managed to get my Torana airborne one night drag racing a mate & his Vh dunnydoor. I was off the clock @ somewhere around 160kph. But i'm not the only one who has done that before. :oops:

Cheers

ToranaGuy
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me217
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:-o thats all i can say.


me217
me217

1985 suzuki mighty boy : mods, f8b
1990 toyota mr2 gt import : mods, turbo timer, short shifter, 2.5" exhaust
1992 suzuki sierra : mods, g16b mpfi, 235's/75, snorkel & lift on the way.
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ike849
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hats off to your g/f that can get the MB on 2 wheels :!: :!: :-o

has anyone else had experience with those tyres fritz mentioned????

i didn't know there was still some options available in the 12" rim still.....was told by un-named tyre seller that 12" tyres are very limited (read trailer tyres), so going bigger was the only option to getting more choice.

i should have named the topic - bigger wheel combo that is "close" to std. weight.

i've checked out a fair few tyre places and the 15"x5.5" rims can weigh anywhere from 6.5kg to 10kg and tyre weights 8kg to 9.5kg. i used my digi bath room scales for the 15" rims so no doubt accuracy could be out by atleast 0.25kg (scales go in 0.5kg increments) to 2kg max i would think??

no shops had 13" or 14" rims on display for me to weigh, but wheelweight.net has them roughly around;
13" 5.5kg to 8kg and tyre weights around 6kg to 9kg.
14" rims weigh 5.5kg to 8.5kg and tyres weigh 6.5kg to 9kg

so excluding forged rims as they are way too expensive and magnesium ones don't well deal with pot holes.
Lightest 15"x5.5" combo ~14.5kg
Heaviest 15"x5.5" combo ~19.5kg

Lightest 14"x5.5" combo ~12.0kg
Heaviest 14"x5.5" combo ~17.5kg

Lightest 13"x5.5" combo ~11.5kg
Heaviest 13"x5.5" combo ~17kg

considering the std. combo weight of 5-6kg (tamon guide) your looking at atleast double the weight. i was told a long time ago by a race engineer(not sure how accurate it is or whether it's a general rule of thumb) that adding 1kg to a wheel weight is equal to adding 2kg to the rest of the car.
so if you got the
lightest 13" wheels is like adding 44kg sack of dirt to the tray of a 'std. wheeled' MB
lightest 14" wheels is like adding 48kg of dirt (best option compared to others, but don't know about availability of 14"x5.5" rims)
lightest 15" wheels is like adding 72kg of dirt :!:

i think your right fritz...if your going to get any aftermarket wheel combo you will have to upgrade the struts to compensate this big increase in unsprung weight. those yoko tyres look like an attractive option!!! :D
Last edited by ike849 on Thu Apr 12, 2007 6:54 pm, edited 5 times in total.
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Brayden
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ike849 wrote: i didn't know there was still some options available in the 12" rim still.....was told by un-named tyre seller that 12" tyres are very limited (read trailer tyres), so going bigger was the only option to getting more choice.
Standard 12" road tyres are available, but there is less choice, and they are more expensive than the majority of 13" tyres simply because of the lack of demand.

Personally I think the weight penalty of upgrading to 13" wheels is well worth it, as you'll make benefits in handling though more grip and less sidewall flex. Besides, stock 12x4" rims are unsuitable for those yoko tyres, and getting suitable 12" alloys is nearly as hard as finding Jesus. :D
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stevan_istheman
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Brayden wrote:Besides, stock 12x4" rims are unsuitable for those yoko tyres, and getting suitable 12" alloys is nearly as hard as finding Jesus. :D
I found Jesus... Twice! :lol: :lol:
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fritz
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Geez!! - & here I was thinking the stock rims were 4.5"... :(
I'll have to put my thinking cap on for some suitable 4.5" rims...
Daihatsu handi/mira?
Older datto 1000/1200. 120y???
Suggestions? :?

You'll find that with 12" tyres there is a moderate amount of performance tyres available because the market for mini stuff is big enough to sustain it. The taller profiles will be difficult to come by. If you're serious about 12" tyres and are having troubles, just try your local mini outlet. :wink:

FYI:- My RJR rims weigh 6.3kg, Tyres are 6.4kg. So 12.7kg all up.
One of my stocker 12" tyre/rims is 8.7kg
:D :D :D
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Brayden
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Fritz, the biggest market for performance mini bits these days is Britain, and a lot of those guys tend to fit 13" rims to clear the bigger aftermarket brakes. Which probably explains the variety of sports and semi's available in that particular size.
I certainly didn't realise that anyone made semi's in 12" anymore though!

As for the stocko rims, I was pretty sure they were 4", but that may be a faded memory. Base MK2/3 Swifts were fitted with 13x4.5" though.

If you're after 12x5" rims I would get onto Performance Alloys and get a set of SuperLites drilled to fit. Rims from a Datto would be RWD offset, and put unnecessary strain on suspension/hub components.
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fritz
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You're right. they are 4.0" - I just thought they were 4.5 for some reason. :?
Brayden wrote:Fritz, the biggest market for performance mini bits these days is Britain, and a lot of those guys tend to fit 13" rims to clear the bigger aftermarket brakes. Which probably explains the variety of sports and semi's available in that particular size.
Sure britain is the home of older minis, but shipping isn't a problem. :)
I'd say pretty much anything mini related is shipped to Oz.
From my limited knowledge of mini tyres, I believe the 13"ers dont work as well on them as the smaller 10s and 12s on minis. So while they may have bigger rims to clear brakes, it means squat if they dont go around corners properly.
The market for 13" tyres is naturally much bigger because all sorts of cars were fitted with that size for decades. But as you know, MBs are pretty much limited to 165s (in lowered form - which surely any performance oriented MB would be). I have yet to come across any 165 13s in race legal tyres. Most are 175 or bigger to suit the vast array of old school RWD 4 cyl cars.

http://www.polleymotorsport.co.uk/tyres/msport/A032.htm
http://www.polleymotorsport.co.uk/tyres/msport/A032.htm

Still, if people want to go the way of 13s, good for them. There's room for all sorts in our community. :wink:
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Brayden
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I should have mentioned that one of the more common performance tyre sizes in 13" is 175/50/R13, which was definately developed with mini's and kei's in mind. ;)
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daronk18
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Brayden wrote:I should have mentioned that one of the more common performance tyre sizes in 13" is 175/50/R13, which was definately developed with mini's and kei's in mind. ;)
i was talking to a tyre place down here the other day and he was saying he cant get 13" in a 50 series only in a 60 or 70?? wait til i see him..
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jono
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Gee, even down here in Tassie I could get 175/50 13's :lol: . You should tell them that! Although at 180 bucks a corner I decided to go with the 165/65's!
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fritz wrote: Sure britain is the home of older minis, but shipping isn't a problem. :)
I'd say pretty much anything mini related is shipped to Oz.
From my limited knowledge of mini tyres, I believe the 13"ers dont work as well on them as the smaller 10s and 12s on minis. So while they may have bigger rims to clear brakes, it means squat if they dont go around corners properly.
Bit of an aside really - but I wouldn't be surprised if there's more old Mini's left on the roads here in Oz than there are in the UK - they tend to 'dissolve' a whole lot less out here :)
As far as wheel sizes go, though, if you want a Mini to handle, you stick with 10x5" wheels and 165x70x10 tyres. . .which are MUCH lighter than 13x7" and 175x50x13. 13's are generally only fitted for looks. . .funnily enough, there was a trend in Japan to buy Rover Minis with factory 12" wheels and retro fit 10's.
Performance tyres are readily available for 10's, 12's and 13's so if anyone tells you any different, they're lying :)
Dunlop Formula R's and Yoko AO32R (I think?) are certainly available in all those sizes.
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ceej
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jono wrote:Gee, even down here in Tassie I could get 175/50 13's :lol: . You should tell them that! Although at 180 bucks a corner I decided to go with the 165/65's!
My ute is running Sime tires in a 175/50/R13 which are cheap as chips, and they still stick like shit to a rug. :wink:
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ToranaGuy
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Talking about all that weight that get's added when you fit larger tyres & rims, well i sure as hell can't tell it when driving my MB with the 165/65 13's, in comparison to it's 145/70 12's. With 13's the car doesn't seem to " bounce " down the road any worse than it used to with the 12's.

Cornor's, you can feel the lower amount of sidewall flex, as the 165 is a nice fit on the 5.5" rims i have, compared to the 145 on 4" rims. There's about 12mm less " balloning " of the tread width over the width of the rim, if that makes any sense.

Something to throw into the equation, my MB was aligned by pedders in Hoppers Xing not too long ago, drivers side was out a country mile, so i had a camber pin kit fit to it, and shocker drive on test done. The shocks, all round, show up as slightly soft, but they still pass RWC. Push down on the mb, it only comes back up, doesn't sit there bouncing.

Considering more weight at the bottom of the spring, i would have thought it would show up them being a bit soft with the larger tyres & rims. It doesn't yet. Maybe they are not as soft as Pedders said they were. I was advised it needs new shocks in the next 3 mths, then the guy checked it up, and said sorry can't get new front shocks. Only reco your's at over $500 for the pair!

Cheers

ToranaGuy
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