How often did you need more than 4 wheels at the competition?

[df_fsmb]

It sounds a bit silly. But seriously, how crucial is it to have 8 wheels at the competition? We are a new team and thus do not have any experience with this - as far as I can understandt the procedures at the competition, the only occasion when 8 wheels would be absolutely necessary is in the event of changing weather during your 22km endurance run.

So, how many times did the most experienced guys on this forum changed tires from dry to rain or viceversa during the endurance?

[df_fsmb]

It sounds a bit silly. But seriously, how crucial is it to have 8 wheels at the competition? We are a new team and thus do not have any experience with this - as far as I can understandt the procedures at the competition, the only occasion when 8 wheels would be absolutely necessary is in the event of changing weather during your 22km endurance run.

So, how many times did the most experienced guys on this forum changed tires from dry to rain or viceversa during the endurance?

[The AFX Master]

If you plan to go to FSAE Michigan, 8 wheels are an absolute must.

FSAE MI does have mixed conditions along the week, going from dry cold to totally wet unpredictably. In fact, conditions can change rapidly while in line for AutoX or Endurance!.

[Dash]

DURING endurance? I have to say I haven't.
In the three minute span right before you start Autocross and it starts to rain - YES!
It is a necessity to have a set of rain tires with you at all times.

While looking at the rules, the only rule on tires is:

B6.4.1 Vehicles may have two types of tires as follows:
• Dry Tires – The tires on the vehicle when it is presented for technical inspection are defined
as its “Dry Tires”. The dry tires may be any size or type. They may be slicks or treaded.
• Rain Tires – Rain tires may be any size or type of treaded or grooved tire.

So if you didn't care too much about destroying some grooved tires in the dry ( and I would ask the rules committee for sure ), I think you could just bring one set of grooved tires. Although that would no doubt be a terrible, terrible idea.

[moose]

Please please make sure you have 2 sets of wheels & tires; It is all but impossible to flip the tires from dry to wet (or vice versa) and get the tires OK'ed and then go use them. You'd need ~1 hr, and the track conditions can change much faster than that. You don't want to miss an event b/c of this.
If you need to have the wets running on a cheapo/heavy set of steel wheels or something, that's still better than the alternative in my opinion & experience. The more prepared you are, the less likely that you'll need that backup plan.

[Lorenzo Pessa]

It would be better to have 9 wheels (5 dry) in case you have a puncture.

[Bemo]

I think the only time we had to use our rain tires at comp was Silverstone 09. We were the first team to start Endurance in the morning and just a minute before the start it started to rain heavily, so we had to switch to wet tires.
The absolute minimum is to bring 8 rims with four dry and four rain tires to the competition. I'm not even sure if you can pass tech if you bring less than that.
As Lorenzo already said, it isn't a bad idea to have spare wheels because you can always have a puncture.
If you don't have spare wheels make sure to really pay attention while pushing the car around the campground to make sure you don't roll it over nails, pieces of glass etc.

[StevenWebb]

if your that strapped for cash i think you have 2 options.

1. only have 1 set of tyres that are suitable for both wet and dry

2. use a common car pcd and use heavy second hand road car wheels for your wets.

[df_fsmb]

Guys, thank you very much for all the information!

I guess we will do everything we can to get us 8 wheels.

Thanks again, really means a lot to hear advice from people with experience.

[Zac]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Dash:
So if you didn't care too much about destroying some grooved tires in the dry ( and I would ask the rules committee for sure ), I think you could just bring one set of grooved tires. Although that would no doubt be a terrible, terrible idea. </div></BLOCKQUOTE>

I would hardly recommend this, but you could possibly get away with using the carved Goodyear D2691's for all the dynamic events (at Michigan anyway, good luck out West...). UWA won a couple years ago on the uncarved version of that tire, and the reduction in net/gross contact area from the tread carving is pretty minor so you won't lose a whole lot of grip. The tires will be pretty well roasted by the end of an endurance run, but at least chunks of tread won't be flying off like some of the molded rains.

Still, I'd recommend getting at least 2 full sets of rims, even if you have to settle for some cheap street car wheels for the second set or have the entire team sell their plasma for a couple weeks.

[coastertrav]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Zac:

...or have the entire team sell their plasma for a couple weeks. </div></BLOCKQUOTE>

We've heavily considered doing this before...

[JasperC]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Bemo:
I think the only time we had to use our rain tires at comp was Silverstone 09. We were the first team to start Endurance in the morning and just a minute before the start it started to rain heavily, so we had to switch to wet tires. </div></BLOCKQUOTE>

Haha, what an epic competition that was. http://fsae.com/groupee_common/emoticons/icon_smile.gif I remember one of Zürich's wheel nuts got stuck while they were changing to wets, so they had to repair their hub in our truck during endurance and they then started in the afternoon with a 2-minute penalty for running out of order. Luckily for them though they didn't have oil and water on the track so I believe they actually finished with a much better time than you and us. A very rare case where running out of order was actually beneficial. http://fsae.com/groupee_common/emoticons/icon_smile.gif

[Bemo]

I think they got the two minute penalty, but were eight minutes or something like that faster than us.
I think I died a couple of times while trying to count all the cones and off courses.

[Kevin Hayward]

To the original poster:

I would recommend bringing 3 sets of wheels with mounted tyres. 2 dry and 1 wet. You are most likely to run on drys and having two scrubbed sets ready to run leaves you pretty safe. This is especially handy if you have time to use the practice track, or want to switch to a fresh set for the endurance.

Having a mounted set of wets should be considered essential. Having to run around and try to change a set of tyres at the comp can set your campaign back quite a bit if things do not go to plan.

Another issue to think about is that the rims that are often used are reasonably easy to damage while mounting tyres (Often they are delivered pre-bent for convenience). This means that you may be dealing with a set of leaking wheels at the comp if you do not have spares. According to Murphy this will occur the day before comp.

Kev

[Michael Royce]

From a Rules standpoint, the wheels for "rain tires" or "wets" do NOT have to be the same as you have for your "dries". Therefore, for teams that are really hard up for cash, a cheap set of wheels, maybe even steel wheels from a scrap yard that have the correct bolt pattern and fit over the hubs and the calipers, would work. And the "wet" tires can be a set of (cheap) passenger car tires, as long as they meet the tread depth requirement. This set up would allow you to run if the track is declared "wet".

[Der Krug]

This is racing. Bring as many wheels/tires as your budget will allow. If you end up bringing to little or too much, adjust for the following year. It's all about finding what works for your team.

[fixitmattman]

2 sets of tires (wet and dry) with only 1 set of rims can be done. We were also flat broke and took that approach once. It's stressful as hell though trying to make that call. If you can afford it bring both mounted at a minimum.