Anyone have an idea of tyre pressures for a 450kg R1 bike engined locost.

I have 185/ 60/13 A032 and A048 tyres at the moment in SS ( super soft?) compound and don't realy know where to start on tyre pressures , everything iv'e had in the past is double the weight so guessing something pretty low PSI is in order but how low?

Cheers in advance

Maybe some useful info here, albeit for a Ford 1300 Crossflow live axle 750 Motor Club race series Locost on Yokohama A539 185 60 R13:
https://www.750mc.co.uk/ugc-1/1/28/0/2018_locost_novice_pack.pdf

750 Motor Club Locost race spec inc weight: https://www.750mc.co.uk/ugc-1/1/1/0/2022_final_regs_-_locost.pdf

Cheers
Mike

[Edited on 5/4/22 by Mike Wood]

[Edited on 5/4/22 by Mike Wood]

Some years ago I built myself a Pinto engined MK Indy for road use. 15" wheels with 195 tyres.

I played around with tyre pressures until I got to (from memory) around

Front 17 psi

Rear 16.5 psi

Those pressures may sound low compared to tin top tyre pressures, but my Indy weighed something like 650kg wet (without me, so 735kg with me). Tin tops are considerably heavier!

Any higher and the car felt skittery on dry summer roads at normal road speeds. I forget the specific tyres, but they certainly weren't track tyres.

It's probably a bit of trial an error, but I bet you'll be at about 15 psi as a starting point. I run my R1R's at 18 psi even on the road. Any more than that and I'm bouncing around.

I used to measure temperature across the carcass and adjust to suit, once they get hot after a few laps they will gain a few PSI so from cold no more than 14PSI, 3 laps then pull in and they should be around 16psi

Driving hard they would be shot after 2 track days with plenty of resting time so I moved to second hand slicks, these lasted much longer and gripped far better and at £15 a corner it’s win win, just keep the others as wets and commute.

When I last used A032 or A048 (many years ago) on a Striker I started at 16-18psi cold and then checked for even tyre temperature during use (track).

I don't think A032 have been made in that size for many years...how old are they? Have you checked the date code? My last set went 'off' long before I wore them out. The were really slippery on road or track, almost lethally so. Think they were about 3-4 years old by the time I ditched them before they ditched me

I run 18psi cold for A048 / R888R. I have tried either side of this and am happy with this.

That's with a 560kg (no driver) striker. 185/60/14.

thanks folks , much appreciated

My cars quite a lot heavier at 700kg with me in it and on a trackday couple weeks ago I started off with 18psi and once the tyres were hot they were up to 24psi!

That's 185/60 13 front and 205/60 13 rear Nankang Ar1's.

I start with 14psi cold on my Locost R1 - 460kg car.

Description

Tyre temperature kit with choice of fast response probes go google - cheap and effective..

Easy to work out tyre pressure too high - too low - excess camber - also corner weight..