Tyres for 10 inch rims

[James Waltman]

Big Daddy,
Combining the hub with the stiffener would be a bad idea. To keep the Douglas wheels you have to keep a standard bolt pattern setup. If you want to be able to change wheels then the stiffener/hub combo must unbolt from the wheel. A stiffener that is removable is severely compromised.

If we go with Jack's idea next year that probably means custom wheels and it doesn't matter anymore.

James Waltman
http://dot.etec.wwu.edu/fsae/
Vehicle Research Institute at
Western Washington University

[wingman]

Hey Big Bird

The heavy steering is a low speed problem due to the steering geometry with the 10" wheels and the available steering rack ratios combined with the scrub radius issues (if memory serves)

At high speed (i.e. a REAL auto-x course) steering input is lower and your only doing one lap at a time, therefore, not an issue

The wings are not a significant factor in this case, aside from the fatigue from all the lateral g's your pulling

[jonno]

just wanted to open up an old thread as I haven't really seen a newer thread on the 10" tyre topic...
so at FS rmit's 10's were fast enough. And the other 2 teams on 10's & singles came 4th & 5th (Delft & Tokyo) in the autocross. With rmit using goodyears, delft running LeConts and Tokyo using Hoosier, it can be assumed that this combination of tyre, engine & size of vehicle is fast. But do any of the 3 mentioned teams have any comparable data between the different tyres?
Also, I'd be interested to hear from delft about how they found the lower walls of the leconts. The reduction in rotational inertia must be quite beneficial (assuming the lecont's are similar construction to the goodyears & the hoosiers). Also, there has been a lot of differing opinions about sidewall flex. The leConts being 16" therefore only have a 3" wall, less than any of the others.
Finally, are there any other recomendable 10" tyres out there other than the 3 listed and can anyone come up with a comprehensive argument (other than comprimised packaging) of why not to drop to 10's from 13's?

[mech5496]

Back from the dead topic here! It just came to my attention that Avon has a 10" FSAE tire listed on their website for 2013. (http://www.avonmotorsport.com/resour...ormula-student) Has anyone used it? Any idea on the available compounds? Any experiences you want to share?

[acedeuce802]

Back from the dead topic here! It just came to my attention that Avon has a 10" FSAE tire listed on their website for 2013. (http://www.avonmotorsport.com/resour...ormula-student) Has anyone used it? Any idea on the available compounds? Any experiences you want to share?

I believe it was Toledo that used that tire this year. I talked briefly with them about it, and they said they weren't happy overall with the tire. We didn't talk much details about it, though.

[Z]

Harry,

My very UNreliable understanding is that those tyres are from the moulds originally made for the front tyres (x4!) of the Tyrell 6-wheel F1 car of 1970s? Mini Minor based race cars were common back then too, and since they came with 10" rims they may have kept the market going.

I believe nowadays they are mainly used in the British hillclimb scene, on the smaller bike-engined specials. I have seen them on some FSAE cars, probably from FSUK. They are quite easy to recognize, with big white "Avon" on the low profile sidewalls, and small OD (which I reckon is their biggest advantage, only ~0.4m, 16").

I understand (again, very unreliably!) that as primarily a "hillclimb" compound they have great grip from cold, great grip for ~1 lap, then overheat and turn to jelly.

Maybe try looking/asking on some British Hillclimb forums? Or, better yet, buy two, and burn rubber!

Z

[mech5496]

Harry,

I understand (again, very unreliably!) that as primarily a "hillclimb" compound they have great grip from cold, great grip for ~1 lap, then overheat and turn to jelly.

Z

That's what I am afraid of! As far as I know, Avon offers many compound options on all other tires, so a super soft and sticky compound would be ideal for accel/skidpad/autox while a harder compound might suit the endurance better. As far as I know teams are allowed to run only one dry compound, so we should test, find the best compromise and then compare to Hoosiers. Their smaller OD is a good thing for us (less rotational inertia, probably lighter, 7.5% shorter final drive (the car is directly driven from the motor) plus IMO they look better! The thing is that the lower overall diameter requires to lift the car by some 10mm thus affecting suspension geometry by a fair bit, but still we might be able to have some conclusions on how they perform. We most probably will buy a set but still I would like to have some insight from someone that has used them before buying!

[Luniz]

We used to run Avon 13" tires until 2011 and we were quite happy after we played around with some different compounds. Avon is a very small company and they have no problem putting together a new tire from any existing components they have lying around. We ended up with the construction of a formula ford front tire with some special compound on it. They were happy to produce four sets/16 tires specially for us. So I suspect they could also make those 10" tires with different compounds if you ask nicely enough ;-)

What Z said about the supersoft compound is actually very much the case, we used that in 2009. Won two accel awards thanks to the sticky stuff but failed miserably in endurance in Hockenheim, because the tires literally disintegrated after 4-5 laps.