What tyre widths are folks running on their road-going litre BEC's?
I'll be using a set of 7 x 16 rims on mine which can accommodate between 195 and 225 width tyres.
I want the car to be fun to drive, so don't want to 'over' tyre it. Besides, with only 85ft/lbs of torque, I'll hardly be setting
the tarmac ablaze! 
Would a 195 / 205 combo be sensible, or 205's all round, or should I really be looking at a more obvious 205 / 225 stagger?
Cheers
Hello Scott!
What are you up to now?
You're right, don't over tyre it. Some of the tyre combinations I've seen are downright dangerous, and must be frightful to drive in
the wet
The locost racecars seem to do ok on 185/60 road tyres. You might have a bit more power, so 195 at most.
And please, don't put big wheels with those silly super low profile tyres on, it'll ride like an old cart and feel every little ripple on
the road.
It's about road pressure, and contact patch shape.
Stay alive, and be sensible.
Cheers,
Nev.
Say hello to the wife and the dog for me. 
13" on 60 profiles seem to work well on lightweight BECs i mean when was the last time you saw low profiles on an F1 car??? a bike engine is
designed for half the weight & tyre contact patch of a BEC so if your tyres are to big the clutch & gearbox are obviously going to fail
quicker
westfield designed the 1300 megabusa, 1100 bird & 900 blade with much R & D so I guess their tyre recommendations must mean something hence
why I'm running 185x60x13 tyres on 6x13 rims at 18psi all round on my megablade, see pop up info on link below
linky
[Edited on 24/8/17 by andyfiggy2002]
I'm running 185/60/13 front and 205/60/13 rear. I've 2 sets of wheels; One is 6.5" front/7"rear and the others are 7"F+R. Not
much difference really but I feel the 185's fit the 6.5" rim better.
Why are you going for 16" rims? I originally had 15" but swapped to 13" and the ride and grip were both better particularly on poorer
surfaces. They are lighter than the 15's I had, so thats a contributory factor but it was a like for like swap I think the weight difference
would be marginal.
andyfiggy, the F1 arguement is a bit of a red herring. The teams use 13" because thats what the regs say. Most teams have expressed a desire to
go to at least 15" as it would give them better control of the suspension (the 13 is acting as an undamped spring).
Ok i stand corrected on the regs of F1, interestingly Formula E goes the other way & uses Michelin Pilot low profiles on 18"s rims where
energy efficiency is more critical & therefore less tyre rolling resistance is best at the expense of being able to generate less heat from
sidewall flex, then again F1 race on faster dedicated tracks whereas formula E use street circuits where cornering speeds are less.
TBH the added weight of the larger rims, the firmer ride, difficulty of getting heat into the less flexible sidewalls and higher cost of these low
profiles would put me off using them on a lightweight BEC
i agree, i'm running 13s also.
The larger sidewall is a good factor to let more heat get into the tyres due to flex.
If you have small stiff sidewalls, you'll struggle to warm up the tyres enough on a car as light as ours
Thanks guys - lots of good info there,
I'm using 16's as I already have a pretty set of forged fella's in my garage loft. Very light as well for their size at 5.6kg.
They also clear the braking components I have - 15's would just be a little too tight.
quote:
Originally posted by andyfiggy2002
Ok i stand corrected on the regs of F1, interestingly Formula E goes the other way & uses Michelin Pilot low profiles on 18"s rims where energy efficiency is more critical & therefore less tyre rolling resistance is best at the expense of being able to generate less heat from sidewall flex, then again F1 race on faster dedicated tracks whereas formula E use street circuits where cornering speeds are less.
TBH the added weight of the larger rims, the firmer ride, difficulty of getting heat into the less flexible sidewalls and higher cost of these low profiles would put me off using them on a lightweight BEC
"Besides, with only 85ft/lbs of torque, I'll hardly be setting the tarmac ablaze!" - a common misconception, bike engines have a reduction gear, usually around 1.6:1 before the gearbox, therefore the actual torque the box receives won't be 85 ft/lbs, but more like 136. With the ZZR 1400 mid engined & on 9" rear rims with 245 or 255 17" tyres if I simply floor it in 1st even on a dry road it will light the back tyres up when it gets to around 6/7000 rpm, & again in 2nd unless tyres are already well warm. Unless you are going for proper sticky road legal "slicks" then I think it would be difficult to "over tyre" on a 7 x 16 rim all IMHO of course!
I am running Toyo R888r's 205/60 r13 on minilites. I know these would be small for your case, but just put my info on in case any one else finds
it helpful.
This tyre in particular is a nice and sticky road legal track day semi slicks, (also quite forgiving on public roads.)
B1257 North Yorkshire Moors TT
[Edited on 10/10/17 by Ian2812]
I'm currently running a set of 6J 14''s with 185/60 tyres whilst my 13''s are en-route and my car definitely drives much
better than on the 7J 15''s with 195/55 tyres
Feels lighter all around,steering and handling wise through fast corners.
quote:
Originally posted by andyfiggy2002
TBH the added weight of the larger rims, the firmer ride, difficulty of getting heat into the less flexible sidewalls and higher cost of these low profiles would put me off using them on a lightweight BEC
quote:
Originally posted by scootz
What tyre widths are folks running on their road-going litre BEC's?
I'll be using a set of 7 x 16 rims on mine which can accommodate between 195 and 225 width tyres.
I want the car to be fun to drive, so don't want to 'over' tyre it. Besides, with only 85ft/lbs of torque, I'll hardly be setting the tarmac ablaze!
Would a 195 / 205 combo be sensible, or 205's all round, or should I really be looking at a more obvious 205 / 225 stagger?
Cheers