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So it's now officially confirmed by Mazda, they're going to add a Wankel powered range extender:


Interesting to see if they sort the emissions and oil consumption issues with what is effectively a two-stroke engine.
 

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I loved my RX8s (I had a blue one, then a silver) and the oil consumption is often exaggerated. But fuel consumption and emissions less so - I need to drive EVs a few more years to make up for my evil, emitting past 馃槇

Unfortunately I can't see it coming to Europe and am not even sure the lovely, but tiny range MX30 will survive until 2023 here (earliest likely date if REX added 2022 in Japan)
 

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I agree Mazda need to do something about range or it will never be more than a niche car. Nevertheless it is on my short list when the i3 comes off lease 16 months from now.

UK VED rules will not favor the REx version. It would be taxed as a PHEV .


The short range version may be little more than a compliance car. Mazda - Toyota need it to meet EU CO2 targets.

Rotary Engine multi electric technology -->

136121
 

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I agree Mazda need to do something about range or it will never be more than a niche car. Nevertheless it is on my short list when the i3 comes off lease 16 months from now.
I too will be interested if used prices are cheap when my 2 year ZE50 PCH ends. Still worried about winter range though...
 

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Kerb weight is 1645kg. That is heavier than I had hopped, given the smallish battery. Mazda know how to make a light car without resorting to carbon fibre.

Mazda say the pack is 35.5kWh which looks like usable not bulk. Charge times would be shorter if that was bulk capacity. For comparison, LEAF 40 is 1600kg with a similar usable capacity.

Perhaps Mazda are being more conservative with safety margins and have a bulk capacity somewhat larger than LEAF 40.



 

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Discussion Starter #8
Kerb weight is 1645kg. That is heavier than I had hopped, given the smallish battery. Mazda know how to make a light car without resorting to carbon fibre.
Remember it's not a dedicated BEV platform, so has all the fixture and fittings for an engine. :)
 

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With a range extender only needing an engine to run at a set rpm, it may be possible to engineer the rotary unit for that rpm level to keep emissions and rotor wear at minimal levels.

Sounds like a lot more aggro that plopping in a 500-600cc 4-stroke unit though.
 

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A rotary engine should be smaller, lighter and smoother than 500cc 4-stroke piston engine with similar output.

AIS 225cs-40 40hp rotary:

10kg
339x274x164mm




 

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Interesting to see if they sort the emissions and oil consumption issues with what is effectively a two-stroke engine.
Having a total loss lubrication system system does not a two stroke make, neither does having ports instead of valves.
The Wankel as employed by Mazda is based around the Otto cycle, of intake, compression, ignition and exhaust. Very much four stroke.
 

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Waste of time in my opinion, in the UK there are too many disadvantages to having a REX/Hybrid, try going to Dundee or London from next year and they will pull your pants down with VED.
 

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With a range extender only needing an engine to run at a set rpm, it may be possible to engineer the rotary unit for that rpm level to keep emissions and rotor wear at minimal levels.

Rotor wear is almost a don't care since the REx motor isn't going to see much use, even in a high mileage car. Mazda have improved the seals. An RX-8 was good for at least 70,000 miles which isn't too bad for a sports car...
 

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And of course REx have less strict emissions tests for the MoT, so even with worn rotor seals etc. it should still pass. Clearly that is not good for the environment, but I suspect that isn't Mazda's true concern at this point.
 

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At 拢25,545.00 to 拢29,845.00 there is a niche for the MX-30. Range and MSRP are about the same as a LEAF 40.

Based on every other recent Mazda I've test driven, it will be a nicer car than most other EVs in that price range.

Mazda do a decent job on the interiors. The fit and finish on two we've owned are as good as anything. Debbie's Mazda 2 has been trouble free for 3 years. My MX-5 had two minor issues both easily fixed. Darn good for a car from the 2nd month of production.


A year from now, I expect there will be discounts or at least 0% finance. We got both on Debbie's car.
 

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I have been a big fan of range extenders having decided it could throw a lifeline to the legacy auto makers. BMW and Nissan have had the right units for a few years and even this Mazda option was on their books two years back. Now with the incredible progress of Tesla I feel all the legacy lot can hope for is to build for those wanting a new second EV in their household for local stuff. I would like a e-Mini or e-208 alongside my model 3 when it arrives.
And the serious thing is, in many households those second vehicles will be the ones that clock up the most miles.
 

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Having a total loss lubrication system system does not a two stroke make, neither does having ports instead of valves.
The Wankel as employed by Mazda is based around the Otto cycle, of intake, compression, ignition and exhaust. Very much four stroke.
but nevertheless, a four stroke that drinks lots of oil...
 

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Seems an odd choice to opt to use an engine that鈥檚 renowned for high emissions and poor efficiency as a range extender in an EV.

The RX8 was heralded for producing around 200hp from a 1300cc engine, these however lacked torque so they weren鈥檛 that thrilling to drive and when you actually look at the way the capacity of a Wankel engine is measured you could argue that it was a lot more than 1300cc because of the way it鈥檚 geometry changed during the rotary cycle.

I鈥檝e never really understood Mazda鈥檚 affinity to the Wankel engine it will be interesting to see how well it does as a generator.
 

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Seems an odd choice to opt to use an engine that鈥檚 renowned for high emissions and poor efficiency as a range extender in an EV.
Those are almost a don't care in REx duty. A range extender is rarely used. I haven't put petrol in our i3 REx in nearly a year.

On the plus side a rotary is light, compact and has low levels of NVH compared to a small piston engine.
 

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Discussion Starter #20
I suspect it can be highly optimised to run a the most efficient speed, which should preserve the moving parts.

A rotary engine is also simpler and so should have less to go wrong.
 
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