I tried lowering my handlebars a bit to see if that improves aerodynamics a bit. I'll try it tomorrow morning and see if it makes much difference.

 

Maybe just changing the tyres and putting a bigger chainring on would do the trick.

 

Nice find! You have the Haibike, go for it! Schwalbe has a wider tyre out this year with fast e-bike certification https://www.schwalbe.com/en/road-reader/schwalbe-e-one.html - wider = more comfortable over a long distance like yours.

 

44 tooth chainwheel = 45 km/h at cadence of 90 + a wide range cassette and how about an aero bar adaptor on your flat bars?

You said:

 

Most of the ride is long straight roads with the occasional town. I work in willesden so only the last bit of the journey is urban and even then they're main roads.

 

When you are on the long straight bits you use the aero bars, the rest of the time you are sat up.

 

I spoke to the bike shop man this morning, he said it would be extremely expensive to convert it to something like the one in the picture. Basically because most of the components would have to be replaced because road bike and mtb components are incompatible. He also said the geometry of the bike might be a bit dodgy at the end of it : (

 

I'll check those tyres out. I'm put off aerobars by the fact that you can't reach the brakes. people drive like idiots around London, wouldn't like to compromise my stopping distance going down a hill.

 

Search for "coupled hydraulic brakes" you could possibly put a second lever out there for the front brake.

 

Use 24 hour lights, not blinky ones, those are used on bicycles and bicycles are slow, no, a nice strong LED one like I have which makes drivers think (just) a little bit more.

 

Try an aero bar it isn't expensive and keep your front suspension fork. That way you have no need of road parts, I looked at the price of a flat bar shifter for a road front derailleur and I know where he is coming from.

 

It will never be as expensive as another bike or using a car...