MUST WATCH if you run WHEEL SPACERS - VERY important SAFETY tip!!!

A quick PSA for anyone that runs wheel spacers for the street or track - this quick test could save you from a LOT of problems in the future, money from repairs, and from possible disaster.
A proper hubcentric spacer slides over the hubcentric lip of the hub, which protrudes approximately 10mm. But the outside diameter of the hub the spacer is covering becomes the same outside diameter that the spacer must have to be hubcentric, so there must be a connector linking the spacer pad to the spacer’s hubcentric snout, which is in the form of a chambered feature. All wheels have a matching chamfer relief, but there is no standard dimension in wheel nor spacer brands for this dimension, and we see it even vary with production runs. And if you are using a spacer with a larger chamfer (typically used to give the spacer more strength) with a wheel that has a minimal chamfer relief, you are at risk of having a failure!
If using a large chamfer spacer with a small chamfer wheel, the wheel will rest against the spacer’s chamfer instead of the spacer pad itself causing the wheel to not be mounted flush. The wheel is never then seated flat on the wheel pad with the wheel studs or bolts providing only a clamping force. Instead, when hitting curbing for example, the hubcentric lip is not loaded as intended, and the load will instead transfer into fasteners, which may result in a premature stud failure. You can see if this spacer to wheel interference has occurred easily by looking for a witness mark along the spacer’s chamfer.
We strongly recommend testing all wheels and spacers you use with what we internally call "the paper test". Once the wheel and spacer are removed from the wheel, place a sheet of standard paper between the spacer face and back of the wheel mating surface and apply pressure. The paper should be captured by the wheel spacer and not able to be pulled out of place. If the spacer “rocks” on the chamfer in the hub then the paper will not be secured and the spacer and wheel have failed the paper test.
If the paper test fails, you should immediately discontinue use of that spacer/wheel combination, and evaluate potential fatigue on your wheel fasteners. When I have been at the track in the past with a small interference, I have used a barrel sander (or even a piece of sandpaper wrapped around a socket) to increase the chamfer relief on a wheel to fit properly - I wouldn't call this the correct solution, but it's gotten me out of a few jams. If you're not as pressed for an immediate solution, a different spacer is a good solution (10mm spacers have the most observed issues because of the more aggressive chamfer required due to the hub's 10mm lip extension - consider moving to a 12mm). If your spacer to wheel interference is excessive, you may have fatigued your wheel fasteners and accelerated replacement may be prudent.
Thank you for reading, and please do share with your track and race friends. The lack of standardized dimensions makes this an issue, but making the paper test a standard part of a fitment test for any new set of wheels or spacers (even if they are the same brand you already own), may save you some headache down the road.
#bimmerworld #safetyfirst #BMW

[@FriendM2010]

Perfect timing. Need to use spacer for first time. Thanks for taking the time to make this video. This is gold. 👍

[@bmws14m3]

Absolute must check. People who complaint about wobble or vibration often have the wrong or cheap wheel spacers. I use BBS and H&R spacers on track only and I still check the wheel and spacers for crack or damage after EVERY track weekend. When you wash your wheel after a weekend events its not just to clean them but look for bend and cracks.

[@g35mr2]

Great points, and please keep in mind that even high quality spacers / wheels can be a mismatch based on how they were manufactured. 👍

[@sandweiler4640]

Very simply presented with logical explanation. I am about to put spacers on my Mazda Mx5 ND2 for daily driving (no tracking intended ever). But I will go for sure for top of the range spacers. Price is not an issue when your life depends on it.

[@fire.dragon1976]

Great info! Pulling my wheels tomorrow to do this paper test. Thanks!

[@gmans7859]

Can only smash the Thumbs Up once. That much more attention to the details. I need to share this Immediately! My son and I are always VERY CAREFUL and VERY CAUTIOUS about the things that are between your butt and the road!

[@bwedges]

I'm going to say something very stupid; if a racecar can use spacer without issues, im going to put it on my road car, as long as i can find high quality spacers and proper installations. You can't stop me this time scotty!!!

[@BimmerWorldMedia]

Oh we certainly aren't saying NOT to run spacers, just need to make sure the ones you ARE running are safe to run. We certainly still run spacers on LOTS of cars around here whether on the street or track.

[@bwedges]

@@BimmerWorldMedia Oh I wasnt being sarcastic haha I am actually going into install it on my car! The scotty part refers to ScottyKilmer on yt who is always against any modifications and loves an old celica. Your explanation has helped me a lot

[@abinalencheri6174]

😂Scotty 🤦🏼

[@Hose-A]

​@@bwedges Rev your engines 😂

[@RENEGADEZZ]

Yep scotty will tell you you're fkn up even if you throw an aftermarket stereo in your car 😂😂 START CHURR 😂😂 ENGINES

[@pngts.g]

Very simple, yet, very informative! Thanks for the video!

[@baduncadonk]

Appreciate this video; learned useful stuff.

[@karlt10]

EXCELLENT information in perfect demonstration

[@MurkSeason308]

This is actually great info, thanks trying to put 2 inch spacers on my 06 ser

[@TunekoLtd]

Thanks for the tips.

[@salami99]

great info! will use this to check new ones

[@stickiefinger5571]

Time to start manufacturing a tool for the general public to buy and take down the material on the wheel or the spacer. Maybe large counter bore or a conical sand paper attachment on a drill.

[@MrRGBTV]

Who knew? Great info and demo, James. Thanks for that!

[@off-roadingexplained8417]

Thanks!!! I will definitely do this test!

[@cyclistman6358]

Interesting and informative video, kudos. One would think that the manufacturers of wheel spacers and wheels would collectively come together and standardized such a critical detail for the safety and well being of their end users. 😳 I still think wheel spacers are a bad idea for street cars for other reasons besides the issue stated here.

[@speedacademy]

Great info, thanks James!

[@JerichoRally]

i would think a proper torque of the lugs would eliminate any minor tolerance issues. especially since the pressure of your thumb makes removing the paper more difficult.

[@BimmerWorldMedia]

But it won't, thats exactly what we are saying here. When its properly torqued it will NOT sit flush and it will pinch the back of the wheel onto the chamfer and the wheel will seat incorrectly therefore putting incorrect load on the wheel studs.

[@j_d8624]

Great video now i feel better about putting spacers on my car.

[@KevinNguyen-zn4vv]

Use a lapping compound to make sure individual spacers is fitted correctly, and avoid buy powdered coated ones? I think most of them are anodized aluminum.

[@karangulati2005]

Great info! Thank you 🙏🏽

[@hamonbagel]

James, Great seeing you this weekend @ CMP. I wish I watched this video before the weekend. After the first of three races, two studs were broken on my right front.

[@gixxerhoff7502]

Great Video. Nothing worse then breaking a wheel stud

[@2be1withU]

Great info. Apex wheel do not recommend 10mm spacers for the same reason. The part where the hub goes into the spacer may not fit flush, leaving a gap between the hub and spacer. So they recommend a minimum of 12mm. I just found this out since I broke a stud (probably from this and also did not swap out studs after certain period of time). Now I understand there is also the fitment issue between the spacer and the wheel. I will check both side of the spacer fitment, hub-spacer-wheel. I installed the Bimmerworld racestuds. A little more costly but shotpeened and each stud individually inspected.

[@lukaszM46]

yeah the issue with them is that the centering ring sticking out of the hub presses against the inside of the bore of the spacer before the back of the spacer can sit on the hub surface. I heard of people that grind down 2mm of the centering ring of the hub so that the spacer can sit flush on the hub surface. I dont really see anything with that, as long as the rest of the fit is fine and you dont plan on going back to running no spacers. this problem doesnt happen on thicker spacers because their bore is deep enough to cover the whole centering ring on the hub

[@scaife5668]

If the spacer lip takes the load as you said how can the spacer that when on wheel moved about a bit , but you said was fine? Doesn't make sense

[@coolname5223]

Good video.... Was/am lookin at spacers...

[@Doug_Hefernen]

Life saving tip!!

[@jasonlockman8792]

Do also use the paper test between the spacer and brake rotor hat?

[@BimmerWorldMedia]

To be completely certain of any possible issues between the rotor hub and spacer it would be smart to check that as well. Same rules apply.

[@stevew8095]

Thank you!

[@mattido123]

Good info! Thx James

[@grantclive3245]

thanks for sharing.

[@dasfahrer8187]

Holy crap that's great info!

[@duvieskytg711]

Hi. Im installing KSP spacers in my Ford SUV, the questions is with torque specification I should be using: from factory or the KSP specification?

[@MeesterQ]

Why not grind the spacer instead of the wheel?

[@R-EVLMNKY]

I know right 🤔😁

[@harryberry474]

Refreshing to see a video on hub and lug centric spacer and more importantly the chamfer on both wheels AND spacers, I've been aware of it for a very long time and it's so important, another thing that wasn't touched on here are hub rings which can add more problems to watch out for because those hub rings chamfers have to match or be deeper than the wheel spacer. To avoid that possible issue I look for wheels that fit my hub W/O hub rings in other words hub centric wheels. A long time ago I learned something that for younger folks might not even know and that little hub that protrudes out from your axle is meant to bear the weight of your car along with centering the wheel and in the beginning aftermarket wheels were made for specific cars to fit like a stock wheel, it was difficult to find aftermarket wheels early on but then aftermarket manufactures started making the hub bore larger on their wheels and those wheels had different hub rings for different cars and here we are today just about any wheel you desire might be able to fit...remember what I said about the axle hub bearing the weight of the vehicle than think about thermo plastic type hub rings see a potential problem there? If you track your car (or Race) better stick with hub centric wheels the trend of one large hub bore for all isn't as prevalent as it once was thank god. Reminds me of "Jaws" you get in the cage, cage goes in water ...shark in water...farwell and adieu.

[@pedrofradera6894]

Good job

[@SebastianMLN]

Great video 👍👍 thank you

[@carminecupani7187]

Cool test.

[@AndreiCristt]

Hub centric rings are needed only for the aftermarket wheels or even for the OEM wheels ? Thank you in advance. Porsche Cayenne with OEM wheels and Japan Racing Spacers. JR Thank you for the paper info. Amazing Please reply with the hub centric rings if I need it or not for the OEM wheels.

[@bm_wuratli6883]

wow great information

[@Slidinsidewayz2009]

Surely a "barrel grinder" approach is dodgy at best! Wouldn't the wheel need to be machined on a lathe to ensure uniformity and accuracy??

[@jamesclay1595]

Less dodgy than not doing it - and at the center of mass, the balance effect is minimal. But sure - if you can do it right, that's always better.

[@aaronli163]

question! you mentioned using a barrel grinder on the inner wheel's hub barrel to clear the hub centric spacers. That i understand. Just wondering if it is also safe to do on the spacer instead (reduce the hub lip on the spacer). Would love to know as i much rather not cut into my inner wheel cos its much more expensive and may affect wheel balance (?)

[@PropDeskJunkie]

Wow…happy I found this. Learned something new today. Thanks Clay!

[@edmunek]

meanwhile for years I am driving on the cheapest spacers. no issues. no vibration... yet.. well. you can always go pro

[@jozeccav123]

Very helpful

[@logtec1162]

What about 5mm ones?

[@erwinmerida8891]

Facts!!!

[@twinturbo8304]

I am taking my spacers out

[@CarlosPerdomo]

So, let me get this straight... You use spacers in race cars?

[@BimmerWorldMedia]

That is correct. The BMW Motorsport M4 GT4 comes from the factory with wheel spacers as do many other GT4 factory homologated racecars. If the spacers are designed correctly and mate to the wheels properly there is absolutely no danger in running them. This is what we are trying to tell people. But IMPROPER wheel spacers are as dangerous in all cases. The Pikes Peak, 1500hp car in the background of this video runs very large spacers, but they mate correctly to their Forgeline wheels and we've had not a single issue or failure throughout running that car over 4yrs up the mountain where safety is absolutely a priority.

[@CarlosPerdomo]

@@BimmerWorldMedia, thanks. That really makes me feel better. I own a 2024 Nissan Z and I just put spacers to bring the rims a little bit more flushed to the edge of the fender. I know that the offset part of the rim is now pushed out more. Just don't want to mess the suspension. The wheels look so much better this way. 🙏

[@BimmerWorldMedia]

@@CarlosPerdomo Again, every car is a different and specific situation that needs to be addressed in a safe way. We are providing a great way to make sure the spacer and wheels fit well together, but there are other areas of the car to be sure is up to the task as well. Things such as extra load/leverage on wheel bearings and suspension for sure and adequate thread engagement on your lug nuts as well of course. As long as you go about it in a safe manner and make sure its mechanically all working properly it should be fine. We certainly are not saying a blanket "running all wheel spacers are fine." here.

[@CarlosPerdomo]

@@BimmerWorldMedia I get it. Thanks so much for your response. I took all pertinent precautions and torque specifications. It rides good. We'll see what happens. Thank you again. 🙏

[@antwonefernandez7554]

Very informative. Nice work.

[@funkyd04]

In California the paper test involves Marijuana

[@oh5148]

😯

[@colettedubose]

Question: I brought universal 20in Mazzi 351 hype rims for my 2015 Genesis G80 Rwd. I have a slide on 8mm spacer and the plastic hub rings 72-67.1mm which fits my car but still leaves a gap/movement still. What do you recommend?

[@syjdmzx]

no part of this area should be plastic, especially if you are saying that your hub centering insert (having this instead of a wheel with the correct Center bore is risky on its own) is plastic

[@massgrave8x]

@@syjdmzx incorrect, friend. the vast majority of hub centric rings are plastic, they are very popular. there are fancy aluminum ones but they are unnecessary. they strictly center the wheel, while the lug nuts/bolts/studs will do the actual clamping and bearing of weight. enkei and other reputable wheel companies sell plastic hub centric rings.

[@fals13b8]

How does. The inner lug nut (spacer lug nut). End up falling out. When. The wall of the wheel is there. Theres no room for a spacer lug nut to come out ( fall off). I would say the. Stud. Broke and hence. Wheel falls off

[@BurntOrangeHorn78]

Wheels spacers is god's way of telling you that your wheels are too narrow and not of the optimal offset.

[@Tre-jj8do]

lolol

[@dennisward4855]

i will never ever run wheel spacers...ever....

[@logtec1162]

What about 5mm ones?