Simon's new Xantia V6 and Leaf blog

[CitroJim]

PS I've read the service manual (not the rebuild one though!) for the 4HP20 cover to cover about 5 times I think. Does that make me a bit sad ?

No, not at all! I do precisely the same thing as you do with all sorts of manuals... A great learning process and even though you may not appreciate it at the time it is amazing just how much sinks in for later recall when that bit of knowledge is required...

[RichardW]

Does it explain why Pug want £360 to 'service' it

Ref the traction control - you might need to switch it off if it's really slippery trying to get away - if both wheels slip, the TC will shut the power off and you will go nowhere; a bit of wheelspin might be just enogh to get you going. It should switch back on at 20 or so mph anyway.

I found Vredestein 4 season tyres (Quatrac 5) in the front size, but they only go down to 195/50R16 for the back.... What an odd combination of tyres!

Might you be able to turn on the pre-heat function via Diagbox?

[lexi]

If you lift the wobbly slabs during a dry spell in summer, you can take out 3" of what is under it. Replace that amount with 5 parts whin dust and one of dry cement, mixed up in a wheelbarrow. Slabs are excellent if put down like that, providing you have consolidated ground underneath. You know yourself, you have to be working at the house on all these things frequently, to get it right and ship shape.
Everything sinks through time and it just has to be lifted and brought up to the surface again so to speak.

[Mandrake]

I found Vredestein 4 season tyres (Quatrac 5) in the front size, but they only go down to 195/50R16 for the back.... What an odd combination of tyres!

Might you be able to turn on the pre-heat function via Diagbox?

Just checked on the car and found the sizes I quoted earlier found on the internet are incorrect! They might be for the US spec car which is quite different.

According to the plate on the door frame (and matching the tyres actually fitted) they are:

Front - 145/65R15 72S
Rear - 175/55R15 77V

Both 15 inch rims not one 15 and one 16! (They still differ in width though)

Does that improve matters or is that even worse ?

PS inches of snow completely vanished without trace by the time I came home - quite a disappearing act it did from the chaos this morning!

[elma]

It's the two speed ratings I'm wondering about. How come the back can go faster than the front?

V rating on the rears is 149mph! It must be the only rating available in the size, seems a bit ott to me.

[Mandrake]

Top speed of the car is 80mph, speed limited...

[elma]

Very odd choice to put v's on the rear. Maybe the extra stiffness in the sidewalls is necessary with the weight of the motors.

[Mandrake]

I doubt it. The whole car weighs only 1150Kg and the motor is the size of a water melon

The battery weighs about 150Kg but it is centrally located so the weight balance of the car is 45/55 front/rear.

[RichardW]

Both those sizes available in Quatrac 5: https://www.vredestein.co.uk/car-suv-va ... duct/3/885 I had Quatrac 3 on some of my cars and pleased with them.

[elma]

I didn't look properly anyway, 77 isn't a very high load rating so suits the car nicely. I really don't get the V speed rating at all, quite optimistic.

Very interesting vehicle, this is the first modern car thats caught my eye in a long time. It wouldn't have if you hadn't bought one but now we're all getting to know it through you I'm quite interested. I don't think it would suit me at all as I mostly do 30 local miles a week and occasionally big mileage at the weekend. The 30 miles costs so little that I enjoy using the V6 and feel quite privileged. However things change and I'm quite intrigued by your new Ion and weather it would be a good money saver in the future.

[white exec]

Did a quick shuftie at a couple of tyre manufacturers for those sizes:
Michelin - zilch
Bridgestone - zilch
Might be Hobson's Choice.

[Mandrake]

Had a proper look at the tyres on the car this morning, turns out they're not the OEM dunlops at all. Three of them are Hankook Kinergy Eco, with the front right being a Victra 510 Maxxis. (Never heard of Victra!)

The one odd tyre on the front might explain why the directional stability at motorway speeds isn't fantastic! (It tends to wander a little and need correcting)

I've found the toe in spec is 3mm +/- 3 mm, so I might also check the toe in with my home made laser alignment system when I get the time.

[elma]

Victra 510 Maxxis. (Never heard of Victra!)

Maxxis is the make, Victra the model. Maxxis fall Into the ditch finder category as far as Im concerned.

[Mandrake]

Victra 510 Maxxis. (Never heard of Victra!)

Maxxis is the make, Victra the model. Maxxis fall Into the ditch finder category as far as Im concerned.

That might explain the eagerness for the front ABS to trigger when braking in snow yesterday! As I said, the regenerative braking (which works on the rear wheels) was able to slow me down very effectively without any skidding even in slippery conditions but the front disc brakes seemed eager to lock and trigger the ABS. So whether that's a s**t tyre or a brake action that is a bit too abrupt, (I do find the friction brakes are a bit abrupt) I'm not sure.

I haven't described it yet but the regenerative braking works like this on the Ion:

When you lift your foot off the accelerator partially or completely while moving at speed the motor performs regenerative braking on the rear wheels to slow you down, and you can see this from the needle moving into the blue charge region. Regeneration from just lifting your foot off the pedal is fairly mild unless you are going fast. However if you touch the brake pedal lightly the first portion of brake pedal travel (about 20% ?) simply increases the regeneration and does not apply the friction brakes. This slows you fairly quickly without using the brake pads, however regeneration dies away below about 10mph. If you press the pedal further it applies the friction brakes.

So to drive most economically you want to slow down early enough that you can do most of your slowing either by just lifting off the accelerator, or only pressing the brake pedal lightly so that you're slowing only through regeneration. Once the needle reaches the white line at the bottom of the blue area you are at full regeneration and any further braking is from the friction brakes.

If the battery is 100% charged you get a small amount of regeneration when lifting off the accelerator but no additional regeneration when pressing the brake pedal lightly - this tends to cause the foot brake action to be a bit abrupt as the friction brake comes in at a point where there normally would already be quite a bit of regeneration. However after you have driven a few miles and drained the battery slightly the regeneration starts working to its full potential...

It's actually quite addictive trying to drive in such a way to maximise regeneration. You want to start slowing early enough that you don't need to use the friction brake until you're under 10mph, and if you need additional braking over just lifting the throttle, feathering the brake pedal to get the needle to just reach the bottom of the blue regeneration section. On significant downhill stretches of road you can actually see the estimated range remaining figure go up.

I remember one trip from Motherwell to East Kilbridge (which is uphill most of the way) the estimated range remaining dropped about 14 miles for 8 miles travelling, however on the 8 mile return trip which was mostly downhill, the estimated range remaining started at 20, crept up to 24 through the downhill section and crept back down to 20 again by the time I got home. So the estimated range remaining when I left to return home was the same as when I got home all thanks to regeneration! This made up for the increased consumption on the uphill leg of the journey.

Edit: Just checked, our altitude at home is 98 metres above sea level, and the destination that I had driven uphill (on average) to get to and then recharged through regeneration on the way home is 188 metres above sea level. So a full 98 metres of gravitational potential energy was "stored" in the car during the uphill segment and retrieved in the return journey and put back into the batteries! (I have no idea what the regeneration efficiency of this car is though, but its certainly better than the 0% of a normal car!)

[CitroJim]

Simon, that's really interesting on how the regenerative braking works...

It's whetted my appetite for having a drive of one now I want to experience it.