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I promised Karl I would post my impressions about the new BFG R1 tires I ordered, so this is the first installment of the R1 saga. The size is 265/35-18.

These tires are WAY wider than their specified size. We all know how tire manufacturers cheat on sizes for the DOT competition tires, but this is about the worst I've seen so far. When I saw the stack the UPS guy left, my gut said I had received the wrong tires. I thought they looked like 285's, so I was concerned they shipped the 285/30's instead; however, reading the sidewall confirmed that they were in fact "265's".

Unmounted, they measure 11 5/16ths wide which converts to a section width of 287mm. My gut feel was spot on. I then measured the bead-to-bead distance in its relaxed state which was 9 5/8". Hence if these were mounted on a 9.5" rim and inflated, their section width would be at least the value I measured +/- a tad. Sigh...

I may just barely have clearance for these tires on the 2003 330i, but it will be very close -- that's assuming that they will actually mount to the 8" and 8.5" stock width rims as the sidewalls are very stiff in the lateral plane similar to V710s but not quite as bad.

Next I pulled out an M5 track tire/wheel which is a 275/35-18 Nitto NT-01 on a 9.5" rim. The inflated section width of that combo measured 10 7/8" which is 276mm...pretty much spot on. I run these all around on that car and have to use a 3mm spacer up front to just barely clear the strut. I'm not even sure I could use these 265 R1s on it without a wider spacer.

Here's a quick pic comparison of the 275 NT-01 vs the 265 R1.



I'll try to get these mounted tomorrow for a test fit.

Chuck

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Current stable:
2019 BMW M2 Competition slicktop 6MT
2011 BMW M3 sedan slicktop 6MT
2007 BMW 328i wagon (slushbox for now)
1975 CanAm 125MX2

I can understand the cheating regarding the basic tire size ( i.e. 265/35-18 ), but not as much on the published section widths, etc. Their own documents show a section width of "10.7" on a 9.5" wide tire. That works out to 272mm published section width. That is a 15mm difference to your measured 287mm which seems pretty significant.

http://www.bfgoodrichtires.com/specs/g- ... /3824.html

Anyhow, I hope it works out for you. If it doesn't maybe you could make a case with the tire vendor that the tires are out of spec and are defective?

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Richard Casto
1972 Porsche 914
2013 Honda Fit Sport
2015 Honda Fit EX
http://motorsport.zyyz.com
Money can't buy happiness, but somehow it's more comfortable to cry in a Porsche than a Kia.

They mount more like a Hoosier than a Kumho, so they should be fine at those widths. Note the rim protector area is better than Kumho, which helps.

I dig 'em! But that's because they gave me seven free sets and I haven't really got anything to compare them to on that car yet.


--Donnie

You were spot on Donnie. I had one rear and one front mounted to test fit today.
Discount Tire (Wakefield) had no trouble mounting them. They REALLY look pinched in on the 8" front rims, not quite as bad on the 8.5" rims. The tread face is sooo wide on these “265s that are really 285s” that the sidewall goes back at an angle to the narrow 8” rim…kind of feel sorry for the tire looking at it.

I would really like to use these tires, but it looks like they aren't going to cut it on the 330i. Up front there is just enough strut clearance, and I think there should be enough fender clearance from eyeballing it without driving the car. In the rear however, there will be fender lip contact upon compression (I put three people in the rear seat and one in the trunk to test)...just enough to cause an issue. I would need to roll that fender lip, and then I think there would be enough clearance.

Is fender lip rolling legal for SCCA stock class? I'm not going to extend the fender in any way -- just flatten the inside lip.

Chuck

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Current stable:
2019 BMW M2 Competition slicktop 6MT
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1975 CanAm 125MX2

Not legal as far as i know Chuck. Sounds like they may not work on the S2000, as the Hoosiers barely fit as it stands.

If you still have them at the next event, id like to stack them side by side with my Hoosiers to see how they compare. Mine are advertised at 275s in the back.

Thanks for the update Chuck!

Edited for capitalization. I posted this from the hotel at Roebling, on my cell phone.

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Karl S.
2014 Baby, 2014 House, 2013 Ford Focus ST, 2013 BMW 328i, 1994 Mercedes E320
(Insert passive aggressive signature line here)

Nope, fender rolling is not legal in stock. You're SOL on that one.


--Donnie

Ok, thanks guys.

I've done more investigation since the last post as I tried once again to measure the section width, this time mounted of course. I measured the 8.5" rim one, and I got roughly 10 5/16-1/2" which equals about 262 to 267mm. So clearly they are pinched in a good bit on the 8.5"rim plus clearly I should know better than to measure unmounted tires in the first place. If we assume 0.2" of section width change per 0.5" of rim width, then that would add 0.4" giving 10.7 to 10.9".

Well, BFG rates the tire at 10.7" (272mm) section width on a 9.5" rim! So I think they are actually much closer to the rated section width than my stupid treatise up above would imply. Hence, why the disparity in fit? I just recently took 265/35 Dunlop SSR R-comps off the car, and they fit fine: http://www.tradebotics.com/Autox/Greenville%202007/ZHP-265-start-line900.jpg

I think the issue in my case is that on the R1 the tread width is essentially identical to the section width (at least when mounted on the 8.5" rim). In the case of most other tires, there is the tread width and then some taper of the sidewall out to max section width, but on the R1 the peak diameter of the tire is "section width wide" at the tread face. That's my theory at the moment anyway, and I'm sticking to it (well, give me a few hours, and I'll have a whole new theory of course ).

At this point, I'm off to try the rear fitment again. I wish I could drive on the tires (or at least the rear one) to see if there really would be contact. I just know it is very close with the suspension loaded as above...sigh...

Karl, I can at least say do not depend on my initial evaluation up above (yet).

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Current stable:
2019 BMW M2 Competition slicktop 6MT
2011 BMW M3 sedan slicktop 6MT
2007 BMW 328i wagon (slushbox for now)
1975 CanAm 125MX2

Ok, I went ahead and test drove the car with just one R1 on the rear. I have very minimal contact under full cornering loading, and it was intermittent. It was just enough to shave most of the little ticks off the outer edge, and you could barely see evidence on the fender lip -- just small bits of rubber. So I think I might be able to get by as is, but at the next autocross that might also mean swapping on the street tires and switching to Tire Class after the first few runs too.

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Current stable:
2019 BMW M2 Competition slicktop 6MT
2011 BMW M3 sedan slicktop 6MT
2007 BMW 328i wagon (slushbox for now)
1975 CanAm 125MX2

Thanks for keeping me in the loop Chuck. I owe you dinner.

The reasons for my concern are as follows. The "money" sizes for a late model S2000 are 245-40-17 front, and 275-40-17 rear in Hoosier A6s. The Kumho V710 is only available (front) in a 245-45-17. They're just all enough that they tear out the buttons that hold the fender liners in the car. Also, the price (casting longevity aside) wouldn't be that different anyway. Once you're spending $1000+ for a set of tires, what's another $100, right?

Well, I'm just concerned that if the R1 is even *more* oversized than Hoosiers have been over the years, the front tires might show the same problems that the 710s do, just as a result of width, not height.

I'm also unclear whether or not the R1 is a "track" tire, an "autocross" tire, or a "both" tire. Since I'm only autocrossing the car, I tend towards a tire that is an "autocross" tire first and foremost. If the R1 turns into a "both" tire, I suppose I could buy a third set of wheels, and run locals on the R1s, and save the A6s for Pros and Nationals...but now we're talking about so much back end cost that I may as well just stick with the A6s.

Right?

Chuck, thanks again for being willing to try the bleeding edge stuff and sharing your experiences. Hope you've got them at Danville next month, since I think you've run A6s on that car at that site and can maybe do a reasonable comparison between the two...

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Karl S.
2014 Baby, 2014 House, 2013 Ford Focus ST, 2013 BMW 328i, 1994 Mercedes E320
(Insert passive aggressive signature line here)

The R1, like the 710, was designed as a road race tire with no thought to autocross, as I understand it. It just so happened that somehow the 710 is a decent road race tire and a really good autocross tire (I say decent, but I don't mean it...I hate the things to road race on). No one has given the R1 a really great shake at autocross that I know of yet, so we just don't know if it's good or not. It'll likely last longer than a Hoosier, but as we know from the 710, that doesn't mean it will necessarily be slower.

The only way we'll really know for sure is back to back testing on the same sizes on the same car on the same day with the same driver.


--Donnie

Re A6s -- I think (fingers crossed) that the tread life of the R1 will greatly exceed that of the A6. I've not had good luck with A6s as you guys know plus I simply do not like their turn-in characteristics on the 330i -- they feel lazy, need higher slip angles for a given level of grip compared to other tires I've recently driven on the track and autox on both the 330 and M5. Clearly that is just a driver issue on my part since A6s sit at the top of the autocross mantle; however, couple it with the very rapid wear rate and the cost in 18" sizes, and it quickly begins to look unappealing.

I've not driven the A6 at Danville (just NCAC last summer, Sanford and Laurinburg), so the only comparison we can make other than my subjective comments will be PAX placement versus other drivers I guess.

That said, at Laurinburg I kept screwing up the far right corner (looking down course from start) where you turn to come back toward the bus. It kept sucking me in and I kept falling for it carrying WAY too much speed -- you would think after one or two runs, I would have solved that issue, but no. Cones, one DNF there, etc..sigh. On my last run I STILL overcooked it but just not quite as bad so I made the cone I had been killing, but I still lost some serious time there having to way overslow the car to not hit “my” cone (not to mention I started the run with major cord showing on the LF ). I was 1 second faster in my 3rd run but just tapped the cone there (got a 69.543). Hence my fastest clean run was a 70.575 while I'm pretty sure I could have run the mid 69's if I could have fixed that one section (I hear Tim and Jr in my ear as I type this, lol).

I'm only going over all of this so that we'll have a better idea of PAX comparisons at Danville. I PAX'd 9th at L'burg, and if I could have captured that 69.543, I would have PAX'd 5th. Granted Danville is a totally different course, different drivers might show up, some won't be there who were at L'burg, etc, etc.

Finally, if I’m just better able to jive with the R1 and make it work for me, that still really doesn’t tell us how it compares with the A6. I like Donnie’s idea…I’ll supply the car with mounted R1s, and I have two still good A6s along with two extra front rims. Now all we need are two more 245/35-18 A6s and two rear 8.5x18 rear rims for the 330 and of course a venue plus a datalogger. The three of us can shake out the two tire sets on my car…

_________________
Current stable:
2019 BMW M2 Competition slicktop 6MT
2011 BMW M3 sedan slicktop 6MT
2007 BMW 328i wagon (slushbox for now)
1975 CanAm 125MX2

Chuck, if things work out like I expect, I will have a pair of new 245/35/18
A6's that I'll sell. I'm doubtful we will ever be able to use them on the Crossfire, due to alignment constraints. If they send them to me, I should be able to give a a decent deal. - AB

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I'm pretty sure you don't like the feel of the A6s because your car is so camber challenged. On the S2000, where I can set it up for pretty much whatever alignment I want, they're money.

I just ordered another set. I could *probaby* make Atlanta on the ones I've got, but they're right on that edge. They've alreaddy got like 50 runs on them.

In the future, I think I'll save the second of the two trip odometers for "autocross miles." My office mate doesn't believe me that an $1100+ set of tires probably lasts less than 50 miles...



The data logger portion of this I can actually help with But I'm not all that sure I want to drive the 330. I've told you how much I covet that car, and I'm afraid sampling the goods may send me down a long and expensive road.

_________________
Karl S.
2014 Baby, 2014 House, 2013 Ford Focus ST, 2013 BMW 328i, 1994 Mercedes E320
(Insert passive aggressive signature line here)

Well, cross that planned PAX comparison plan off the list. We put the matching rear sway bar on the car a few weeks ago for a BMW club event, and it is still on it now. Hence I guess we'll have to run in DSP as opposed to DS tomorrow. It is 21mm versus stock 18mm, and that is the only mod that will put the car in DSP, so its DSP PAX time surely can't be very impressive since it could be running springs, camber plates, limited slip diff, amongst many other mods in DSP. I see the DSP PAX multiplier is about the same as AS -- perhaps I should just run it in your class Karl.

_________________
Current stable:
2019 BMW M2 Competition slicktop 6MT
2011 BMW M3 sedan slicktop 6MT
2007 BMW 328i wagon (slushbox for now)
1975 CanAm 125MX2

Oh well...without rolling the rear fender lips, the 265/35 BFG R1s scarp too much under hard cornering. I checked them out today, and it just isn't going to work. Jackie is going to drive in Tire Class (well street tires in LAD I guess) tomorrow as she wants to drive the zhp for her last autox before leaving for college, and I'm going to bring the E90 330i for DS (this car is 100% stock including stock alignment too) since the BFGs fit it ok (tested that today too).

_________________
Current stable:
2019 BMW M2 Competition slicktop 6MT
2011 BMW M3 sedan slicktop 6MT
2007 BMW 328i wagon (slushbox for now)
1975 CanAm 125MX2