General topics » RDC not correct

2km into my trip,

Stopped at a gas station, got my tires inflated with those machines where you give in the desired pressure and connect it after putting those numbers in.

I use 2.2 front 2.5 rear, Michelin PR5.
Topbox with light backpack in it.

So I continued, the dash was telling me 2.0/2.2

Couple km's further I stopped at a car mechanic shop, kindly asked if they could set the pressure correct. They have an analogue hand pump powered by a compressor.
I asked for 2.3/2.6, and so they did free of charge.

Straight after, RDC read out 2.2/2.4

Something 's not right here....

Suggestions?

Hope this helps

I run 2.6 fr 3.0 rear, cold that's 36/42psi, hot rises to 2.7 and 3.1.

Ged

Remember the tyre pressure monitors correct the pressure to 20 centigrade so if the tyres were warm when you pumped them up you would have set the pressure at a higher temperature, therefore the tpms will read lower. Incidentally why are you running your tyres so low, should be 2.5/2.9 front/rear at 20c.

2.5/2.9 is way too hard, this is imo set for max load and 2 persons.

If I'm driving solo with just a topbox that is slightly filled I run 2.3/2.5 cold.
2.5/2.9 with nothing on your bike is just too harsh,
If I go on trips solo with side panniers filled and 2 35l bags on the bike I run 2.5/2.7

I'm not the heaviest person either, 72kg.

I like it like that, feels better and my fuel consumption hasn't changed a bit. 5.2l/100km.

And if the guys at the tire center look up the recommended pressure by means of the charts provided by autodatagroup you find lower recommendations too.

I rode about 6000km's on the oem recommended settings, I will never change back.

I knew there was compensation, but it has always been around 0.1 Now there's a lot more, maybe because of the warmer temp, which I doubt because in 43°C the correction was also 0.1.
Now the gap is getting bigger,
Maybe a sign the batteries in the sensors are deteriorating?

I just use the RDC display to let me know the tyres are still “pumped up”. The actual number doesn’t bother me too much.

I’d never stop to double check a 0.1 delta.

Riding solo all the time I may run a bit less than 36/42 when just using the top box, but I cant be bothered with trying lots of different pressures. I agree with the above comment regarding default pressures suiting a full load, etc.

Anything close to, but not exceeding 36/42 will be fine.

I recently started a 2 week trip with full panniers every day with tyres at 37/43 on my (pretty reliable home gauge) and happily rode over 2,000 miles without any further checks other than looking at the RDC each day to reassure myself the tyres were still “pumped up”.

Over a wide range of speeds and temperatures the tyres didn’t miss a beat.

It’s the 21st century. Tyres are good. Pressures are important, but actual number is not hyper-critical.

Like oil and water - as long as you have “some” then you’re probably OK.

As an aside, I’m astonished how much my son reduces tyre pressure when he takes his sports bike on a track session to avoid overheating the tyres.

Boxerboy. I'm not sure I get what you are saying. The more you lower the tire pressure for the track, the hotter the tires will get. More pressure = cooler tire. Grip vs pressure is another debate.

this getting interesting to me, as I thought the tyre pressure variation reported (according to RDC) was unusual. originally running on 34/43? the front jumped +2 psi very quickly but the rear remained constant, which someone might be able explain to me
with the increased temperatures I had dropped the pressures (a bit not measured) so running currently (start/running) as 2.3-2.4/2.8-2.9 bar (usually 2.8)