Just wondering about tire pressures for a 1992 907ie.
My owners manual states 2.2bar (front) and 2.5bar (rear). How ever the official work shop manual states 2.9 bar front and rear.
I went for a ride using the owners manual settings the other day for about 250km down the Great Ocean rd, lots of winding curves. The steering felt sluggish and noticed scalloping of the front tire. It felt better with the higher pressure, but 2.9 bar seems a lot.
Any thoughts?


Davo

907ie
1098

Davo , Just did the G.O.R. on my 907, found the surfaces to be chopped up , but was running 32 psi (2.2 bar) front and 36 psi (2.5 bar ) rear. even with the touring gear on this seemed adequate. My tires were pretty stuffed at that time got a new set on in Melbourne. I've found the above figures to be about correct in most circumstances,only need to adjust for pillion ,2.9 bar is over 40 psi. , doubtful that you would need this pressure unless carting a small elephant. I think 38psi (2.7 bar ) is about as high as I would go on rear , and incremental on front to suit. What sort of tyres are you on at the moment? Cheers, Marty

Hi Marty, thanks for your reply. I'm generally down the Great Ocean rd most Sundays. It is actually better than it has been……
Anyway I am running Metzlers at the moment. They have a good amount of tread, but they are old. The bike sat around for ages. I have a new set of Bridgestone Battlax to go on. But I want to sort out what pressure is best.

When I had them pumped up to 2.9 bar (41psi approx) I felt they slide around. I thought it was maybe because the pressure was to much, not allowing them to heat up. Then again it could be because the rubber has gotten harder because of it's age?
Have you always run those pressures?

Regards
Davo

907ie
1098

Sorry about delay on reply Davo, On the tire pressure thing , yes I have always ran with these types of pressures , dont know if its a relic from the past ,but I have never had any worries at these pressures , Saw an interesting letter in AMCN recently where on track days they were running up to 42 PSI so it could all be relevant , normally though I would stick with the Handbook specs , Be safe,,,,,,,,, Marty

I run the stock pressures with Michelin Pilot sports. If you want to know if that is enough, set the pressures, go for a 20 minute ride on the highway and recheck them. They should be 2 psi higher. If more, then you need to go up in pressure.

Hi Shelboss, thanks for the tip. I`ll give it a try.
Does anyone know why the pressures are so high in the work shop manual?

Hi All, I finally got rid of those old Metzlers and put on a new set of Bridgstone Battlax BT020. What a difference that made. So much more grip when cornering. Which made me realise hard tyres can actually become if they sit around for extended periods of time and the fact I should have gotten rid of them ages ago the only reason was they had heaps of tread left. The bike shop advised 36front and 38rear taking off 2 psi for sports and adding 2 psi for touring. I ran the 36/38 which seemed fine for a mixture of both.