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View Full Version : picking minilite style wheels-things to consider



trfourtune
08-25-2009, 10:44 AM
With the latest discussions on minilite style wheels, i would like to make the following points to consider:
1. aluminum style wheels are stiffer and deflect less than wire wheels and steel wheels around corners which quickens up the steering response.
2. as the width of the wheel changes, the offset requirement changes to give the same distance from the face of the wheel hub to the inside wheel edge (the critical clearance to suspension-usually).
ie for a 4.5" wide wheel with zero offset, the distance from the mounting face to the inside wheel edge is approx. 2.25". For a 6" wide wheel with a zero offset, that distance would be 3".
3. Wheel price is usually directly related to the quality of the wheel. Quality has a number of criteria besides the common tolerances of production (how round and perfectly square it is-runout etc). Many wheels (most) are cast aluminum. Casting quality varies with different manufacturers (air bubbles in the casting). The actual process makes a difference as well as the consistency and quality of the metallurgy.
Quality can also be how light the wheel is and how strong it is. Forged wheels typically have stronger material and can be made lighter because of the stronger material. These are typically the best wheels. Avoid a really light weight cast aluminum wheel-no strength or brittle. Light weight aluminum wheels are not cheap.
Magnesium wheels typically are very light and have good strength BUT they require proper care. They MUST be coated/painted and should be crack checked on a regular basis. If you scratch them, they should/must be paint touch-up coated asap. Magnesium pits/corrodes badly when not coated and can fail because of it. These are for racing and VERY diligent owners. They are expensive and most manufacturers strongly reccomend not using them on the street.
4. you get what you pay for. Let me say that again-you get what you pay for!
If you don't know who made the wheels, you have no idea what you have. Many if not most wheels are made for looks-junk! If they cannot or will not supply the specifications of the material and strength of the material in the wheel-walk away.
5. Relly good light weight wheels improve the handling of your car. Most aluminum wheels weigh the same as the steel wheels on you car. they will be stiffer, but that may be all.
Light weight wheels reduce the unsprung weight on you car which improves the ability of the wheel/tire to follow the road surface-better grip. Light weight wheels can improve the smoothness of the ride because of the unsprung weight reduction.
6. light weight wheels can reduce the total weight of your car by 20+ lbs. Well thats not much you say, but thats unsprung weight.
7. Curbs are the death of lightweight wheels. If you run your lightweight wheels against a curb parallel parking-you just ruined the wheel. They can take some abuse but be warned.
8. lightweight wheels for a triumph can be 10lbs or less depending on size. Most aluminum wheels for triumphs are around 16-20lbs. I have seen 15x5.5" wheels as light as 8 lbs each.
Have a good day
Rob

CurtisJ
08-25-2009, 11:10 AM
As Rob wrote, wheels are unsprung weight, and thus their weight affects ride quality and handling more directly than weight somewhere else on the car.

It should also be pointed out that wheels turn. Seriously. Since they spin, they have similar inertia characteristic as the engine's flywheel. Okay, they spin at a lower RPM, but that argument is canceled out by the fact that there are four of them. Lighter weight wheels will certainly improve acceleration and braking because of flywheel effect.

Something interesting about flywheels of any kind is that weight distribution matters a lot. How far is the mass, on average, from the axis of rotation? This distance is called is the "moment of inertia". Have you ever seen a flywheel that had a thick rim around its outer edge? The reason is that two flywheels of equal mass will behave differently IF they have two different moments of inertia. With weight further from the axis of rotation, a flywheel's energy storing effectiveness will be greater. Why does this matter? For one thing, wire wheels typically have a relatively long moment of inertia compared to alloy wheels of equal size and weight. Wider wheels have a relatively long moment of inertia compared to narrow wheels of the same diameter.

Don't forget the mass of larger sized tires!

Then there's one other interesting characteristic of flywheels. They always act as gyroscopes. Once they're turning, they resist changes to the orientation of their axis. Gyroscopic effect in the spinning wheels affects handling too, but the physics gets complicated fast so I'll quit while I'm ahead.

re: #7 - When shopping for tires, note that some tires are designed with a protective rib that helps quite a lot to shield the wheel rim from abrasion against curbs.

trfourtune
08-25-2009, 11:17 AM
Curtisj-yes,yes
R

PeterK
08-25-2009, 12:20 PM
Tire weight varies a LOT from brand to brand, model to model as well. SOmetimes as much as 4lbs lighter for the same size tire.

Although I've never seen 8-10lb aluminum alloy wheels used for street use, they probably exist if you're willing to pay the premium. Street wheels are usually in the 16-20lb range for 15x6-ish.

My Revolution 5-spoke wheels have a very thick (2-3/4" thick x 5-3/4 diameter) strong center hub but the rest of the wheel is light to reduce the mass at the edges. I've never seen another wheel built like this and they require special really l o n g wheel nuts.

Watch out for toll booths, they usually have tall curbing, sometimes slanted towards the lane. Can really make some nice scratches in your rims if you turn your front wheels out while pulling away from the tool gate (don't ask.)

edit: One more thing - if you find that the wheel requires a big chunk of weight to get it balanced, have the tire tech mark the light spot on the wheel then, break the bead and spin the tire 180deg, then try the balance again. New tires have colored spots on them to designate high (orange) and low (green) weights, So optimally, with new tires, you'd spin the unmounted wheel and mark the low spot, then mount the tire matching the orange dot with the low spot. (btw - I tip my tire tech)

trfourtune
08-25-2009, 12:29 PM
Peter,Yes,yes
Those are good wheels-good design. I can't seem to find a weight for them, can you tell me what yours weigh and what size they are?
thanks
Rob
ps-i think you mean toll booths, not tool booths

PeterK
08-25-2009, 01:56 PM
Yes Toll booths. Thanks.

The Revo 5-spoke 15x6 is around 18lbs. Not as light as some but the bulk of the weight is at the center as I said. The outer rim is the thickness of a steel wheel. So it's not all apples to apples as you compare wheels. I noticed that Revolution Wheel is also the maker/wholesaler? of KN Minator wheels as well, as listed on their UK website.

Tabcon
08-25-2009, 02:03 PM
Very good points Rob.

I've been through 2 different sets of aluminum wheels and sent every set back.

The first set were the "knock off" style offered in the Moss catalog as "Knockoff Wheels - Minilite". Aparantly, they are not only "knockoffs" in terms of their use, but also knockoffs of genuine Minilite's since they are not actually made by Minilite in the UK. The crazy thing is that even the new "Minilite" whees are knockoffs of the original Minilites and are no longer made by the same company that went out of business years ago. I returned them because they were heavy as heck and looked funky with that chromed center ring.

The next set I bought were made by "Superlite". I liked the wheels but they didn't fit my car as the offset was way too large. I may have bought another set of these but they didn't offer them in the correct offset for the TR4 at the time. They were much lighter than the first set, but they were rather plain looking. The rims were supposed to be polished, but they were not.

I've been looking at several other makes, Panasport, Konig, Revolution, but have yet to really hook up with what I'm searching for. The TR's have been fitted with the Minilite/Panasport style for so long, I'm having a hard time imagining any other style on the TR. I've always like Fiske, but I'm not sure what they would look like on a TR4. If price is any indication, than Fiske should be very good wheels.

I photoshopped them onto a TR4 and I think they look alright, but still not doing it for me. I've also been looking at some Compomotive.

https://www.me.com/ro/taberconstruction/Galleries/100015/Capture-tr/web.jpg

trfourtune
08-25-2009, 02:50 PM
I don't think you will find a wheel to fit your car from fiske. I hope to go with watanabe wheels if I can still get them when i have the cash-$500+ each. ouch!
https://www.watanabewheel.com/
ps-correct wheel not listed on the US dealer site-must be custom ordered to get the correct offset-magnesium

tr8todd
08-25-2009, 03:28 PM
I have yet to see a minilite style wheel that is under 10 pounds for the size I need. My favorite lightweight wheel so far is a 15X7 Enkei RPF1 which weighs in at 9.7 pounds. It is a very strong wheel, and they cost less than $200 a piece. They are one of the most common wheels seen at SCCA events in classes that don't have a minimum wheel weight rule. Spec Miata uses a 15X7, but minimum weight allowed is 13 pounds. I have a set of Rota RB minilites, and a set of Konig Rewinds that weigh in at around 14 pounds each. I also had a set of Panasports that weighed 16.5 pounds each. Once again, those were all 15X7s. Here is a picture of some 16X8 Enkeis on my street car. They weigh 13 pounds each.

martx-5
08-25-2009, 04:01 PM
I've got a set of Rota Slipstreams (https://www.rotawheels.com/wheels.asp?wheelid=40) on my Miata in 15x6.5 size. The slipstreams have a good reputation of being a very strong wheel and they weigh just under 12 lbs. They can be had for less the $150/wheel.

trfourtune
08-25-2009, 04:51 PM
the problem with finding wheels for a tr (not tr7's or 8's)is the back spacing/offset and 4X114.3 bolt pattern. In a 15"x6" wheel for a tr4,4a,5,250 the offset needs to be around zero to +6. There are very few choices. Others will not fit unless you install really thick spacers. Most modern wheels are +35 to +45 offset. The tr6 can handle a slightly wider rim. The suspension won't allow +35 offset without interference. Apples and Bannanas.
here is some useful info:
https://www.rsracing.com/tech-wheel.html#backspace
Rob
ps-yes there are a lot of lightweight good quality wheels out there for other cars, just not that many for ours. After all, we are only talking about triumphs here.

TR6BILL
08-25-2009, 06:29 PM
Panasports are the only way to fly......