Tyre Advice

[BugMan]

OK team here we go again as I’m on the hunt for advice, this time on tyres.  Originally, I was going to have the tyres from WF, but after consultations with the forum, and some good advice I chose just to order the rims.  I’m now at the stage of having my chassis build to the point of just fitted 2 of the rims on one side as a first pass fitting, ready in a couple of weeks to drop onto axel stands (still have lots of jobs to complete yet).

Now I’m no sort of expert on tyres, having driven company cars for the last 30 odd year its always been a case of copying what was on the fitted wheel or just getting a man to fix it for me, so don’t want to screw this up.

Now my rims are WF suppled “Team Dynamic PRO RACE 1.2” and have these numbers on them, and the boxes: -

• Rear are 8” wide and have “5K2-58024H1” by what I assume are 15”
• Front are 7” wide and have “5K2-57040H1” again by 15”

I had an eMail from WF stating I needed “205x50x15” tyres, but to me that translate to 205mm wide, which is about right for my rough measurement of the rear rim of about 8”, but that does not work for the front 7”, which I assume would be 195, so “195x50x15”

I had decided to fit “Toyo R1R” as my tyre of choice, after the original discussion on the forum, so my question is what do I need to order now to make sure I get the right tyres to fit, and also any suggestions on the best supplier?

I’m assuming I can then take them all to a local garage and get them fitted and balanced?

 

[wizzer]

Hi Bug

I was going to fit r1rs but they are not e marked and aren't being made anymore, so any tyres that are for sale are old stock. I was told demon tweeks bought all the stock so when there gone there gone. I fitted federal rsr been told there very good. You could go 215 or 225 rear and 195 or 205 front . I have 7 inch with 205 all round. What did wf recomend

Tony

[Kit Car Electronics]

205/50/15 will be fine on 7" rim and will give you more ground sump clearance than 195/50/15 which will be useful.

[Kit Car Electronics]

Here is another interesting option (I don't know if they fit though as the diameter is slightly larger than 205/50/15) - 195/55/15 (very good price from JJC at the moment £250 for 4, delivered)  

http://www.ebay.co.uk/itm/4-x-195-55-15-82V-Toyo-R1-R-Track-Day-Performance-Road-Racing-Car-Tyres-/361562399761?hash=item542ecc6411

 

[Andy (Sycho)]

I have the same wheel all be it with r888 tyres, I build mine with 205x50x15 on the front & 215x50x15 on the rear. Don't think you will get 215 in R1r's but 225 will certainly fit or you could just run 205's all round which I'm doing at the moment.

You can see spec here & what rim size is recommended 

https://www.toyotires.com/tire/pattern/proxes-r1r-extreme-performance-summer-tires

 

You may struggle to find some sizes of R1r's though.

[Alan Cutler (Adge) - Dorset AO]

2 hours ago, Kit Car Electronics said:

205/50/15 will be fine on 7" rim and will give you more ground sump clearance than 195/50/15 which will be useful.

Think you'll find you need all the sump ground clearance you can get on a 250. The sump is rather low, you certainly won't be grinding the chassis hoop down 

if you stick with 205/50/15 on the rear it will make life simple for Mark (WF) to supply a speedo calibration certificate for IVA. If you decide on a different size for the rear, suggest you have a word with him before parting with £'s, 

[Steve (sdh2903)]

Just for info on the toyo website I found that they list a 7.5" wide wheel as the widest approved rim for a 205 50 15 tyre. Westfield supply them with these though and lots of people fit the 205s to the 8" wide rims as Did I with no noticeable issues.

Tyres are always going to be fighting a losing battle against the torque of the s250. I've championed the r1r as they were superb on my 1st kit with an r1 motor. However I was pretty unimpressed with them on the 250. They broke traction very easily. The r888r were great when warm and dry but scary in the wet.

If I were in your position id be fitting the widest section tyres I could get to fit on the back. Maybe a bit of research on what widths will fit? The extra 10% of a 225 vs a 205 would be beneficial on that car.

For the Speedo calcs I never even got asked for a calibration sheet at IVA. Good job as Mark wouldn't give me a copy anyway.

[BigSkyBrad]

The Toyo approved rim widths for the following tyres are as follows. The recommended width is in bold - 8” is a stretch, so tyre/handling performance will suffer and the rims will be more susceptible to kerbing.

195/50-15   5.5 - 6 - 7

205/50-15   5.5 - 6.5 - 7.5

[Ian Kinder (Bagpuss) - Joint Peak District AO]

8 minutes ago, BigSkyBrad said:

The Toyo approved rim widths for the following tyres are as follows. The recommended width is in bold - 8” is a stretch, so tyre/handling performance will suffer and the rims will be more susceptible to kerbing.

195/50-15   5.5 - 6 - 7

205/50-15   5.5 - 6.5 - 7.5

Hi @BigSkyBrad, these recommendations will be based most likely on tin tops weights and pressures. I've got 205/50/15's rear tyres on 8" rims and they don't look streched to me. The pics below aren't really at the best angle, however.

[CosKev]

Pretty sure the toyo semi-slicks are more bulbous than a standard road tyre in 205?

I know people on Tin tops have had arch clearance issues going from road tyres to the same size Toyo semi-slicks

[Andy (Sycho)]

Here's a picture for comparison against Ian's photo, these are 215.

Personally I can't see why you wouldn't fit a wider tyre (especially with your power) if you have the wider rims. They do look better & give more grip, I will be changing mine back this year. I only fitted 205 as that's all I could get my hands on quick at the time.

[BigSkyBrad]

@IanK (Bagpuss) True, the Westfield are considerably lighter , and the pressures are adjusted accordingly. And yes, yours aren't streeeeeeetched (just not Toyo recommended)

A good amount of a tyre's grip is provided by the sidewall when cornering, smoothing subtle shifts to help prevent break-away - this is achieved by having a little sidewall bulge. In the case of your R888's, a good gauge is the wee lip at the edge of your tread, which should be at least in line (or greater) with your rim edge.

[Dave Eastwood (Gadgetman) - Club Chairman]

That’s generic website information, don’t forget.

When I asked Toyo’s Motorsport technical guru at a Westfield Open day, about the wheel tyre combination, (with regard to my R1R’s, to be sure), he saw no issues and remarked that it was a popular one in the kit car fraternity.

[BigSkyBrad]

Granted, the Westfield is not your average kettle of fish. And a 50 profile is alot more forgiving than a 40 profile. 

My car has 205's on 7", and to be honest I'd prefer a wee bit more bulge, but to be fair they are MOR Uniroyals and hardly track oriented tyres. I've used T1-R's on 6.5" (195 and 205) on all my MX5's and reckon they had just the right look on that sized rim. However, 6.5 rims are not common and the range of styles very limited, and I was lucky to have had the one set of RS Watanabe's that came with me from NZ, that went from car to car - 15x6.5" is a common JDM size but not, it seems, here in Europe.

For the generics of us out there... http://www.toyo.co.uk/tirefinder/index/width/205/aspect/50/rim/15

[Peter (Monty)]

I have R1Rs, 205 all round but I have 7" rims front and rear. R1Rs don't come in 215 wide, the next size up is 225 and Westfield suggested the clearances inside the wheel arch with a 225 might be a bit close (although people may have fitted 225s without issue?).

I like the R1Rs as a middle ground, more water clearance than R888s but more grip than other road tyres like T1Rs. Hopefully a replacement will come out by the time I need to replace mine!

I've also heard good things about Nankang tyres, as another option.