Cycle Security/Anti Theft

There is no real safe answer. You can use locks securing bikes to the rack and each other if two bikes are on rack. Remove the batteries for weight & security. Better still lock them to the tow bar frame if you have a tow bar. I used to fasten a long laptop lock cable to the bikes under the covers and pop the cable into the exterior locker door with a padlock on the end hoping it would look like extra security and hoping I’d hear it rattling if someone disturbed it. 
I also used the cable to secure my Cadac when leaving it at the back of the MH overnight. (Saved it being stolen once).

it is worth checking out your location. Does the site have a bike store? Don’t park up against public paths which give easy access to the back of you MH. Ask the wardens what’s going on.

The D locks are meant to be the best

There are also loud bike alarms available.

As keen cyclists and wanting to keep our ebikes away from prying eyes meant that a MH with a proper garage was a given when we changed vans (after two Swifts) 7 years ago. 
as garages with the required internal height only seemed then to be from European manufacturers, that's where we looked....

Our van is only 6.4M long (and slim at 2.12m wide) but has a large garage under the rear bed.

I don't see the point in buying (say) a 6m van and then having to attach a bike rack (tow ball style) which then adds another metre to the van.

along with the bikes, the garage is great for outdoor chairs/tables, spare wheel, hoses/leads, water container, washing line etc, etc...

plenty of used continental vans about but we are now on our second van with a garage and wouldn't have one without.

when on site, if not put away, we use sold secure cables and hefty D locks.

What a wonderful world. Lock it up or lose it. Great!

I'd probably qualify that a bit, it depends largely where you are....leave it at Clumber Park out in the open.....?

OTOH, many campers leave their ebikes parked up all over the site here in Spain, even on pitches unlocked while at the bar!

folk here seem to have more to enjoy than trying to nick a bike...they all have one, anyway!😉

Security of your e-bikes is always a worry but, in my experience, the risks are quite low if they are kept locked out of sight under a sturdy bike cover or in a MH garage.

In transit we keep our bikes on the high level bike rack, secured with a security cable. They are also covered by a heavy duty bike cover which is secured by lots of straps (a pain to remove), or under a lightweight Fiamma Bike cover if they are in constant use.

On site, we use the security cable through the bike frames and wind it around a tree/lamp post or through an alloy wheel on the MH. We also use the bike cover to keep them out of sight and covered from the elements.

Two other points :
1. Insurance – read the policy wording covering your bikes as many restrict cover for theft from a motor vehicle or in the open. Some require security devices to meet certain standards. Also, make sure the policy covers Public Liability third party risks when you are riding.
2. Payload – e-bikes are quite heavy and many MHs are operated at the max limit of the rear axle capacity. Carrying e-bikes may mean your MH is overloaded.

We have used e-bikes for over 10 years and have enjoyed the mobility they give.  Don't let security concerns put you off - take sensible precautions and enjoy !

Great post, Jim 👍

Adria Compact per chance?

Yes check your insurance wording, apart from which lock are deemed necessary it may give details about cycle racks, ours does:

Immovable Object
Any of the following:
i) a solid object fixed onto or into brick, stone, concrete or metal
and which cannot be undone or removed with or lifted under
or over the Cycle; or
ii) a securely fixed purpose built motor vehicle roof rack or Cycle
rack; or

I actually wanted our insurer to confirm in writing that they considered a touring caravan that is static on a campsite pitch to be an immoveable object for the purposes of the insurance and that they were happy with my bikes being tethered through a chain and heavy duty padlock to the caravan itself. I do this by threading a heavy chain through the cornersteady which is a triangle on our model and then chaining both bikes together. The insurer was happy with this.

At the end of the day a determined thief will, given the right opportunity and time, get through most locks and security devices. You are just hoping the deterrent makes them look elsewhere.

2. Payload – e-bikes are quite heavy and many MHs are operated at the max limit of the rear axle capacity. Carrying e-bikes may mean your MH is overloaded.

There are several "lightweight" ebikes on the market. We found some that weigh 15.5 kgs with the battery incorporated into the frame and looked at several others last year before buying our present ones.