I think it unlikely the Honda plate can be adapted to take a Givi box.
In any case, I'd get the proper Givi mount.
I have a Monokey V56 Givi box and have come to the conclusion it's a bit heavy for me to deal with now; it raises the CoG on my Forza 350.
I might have been better buying a Monolock box.
Doubtless, other riders here will have opinions based on experience.
Hang on before doing anything to hear from them, too.
Incidentally, I have a Shad box on my Honda Vision 110.
It's a good box and cheaper and lighter than many of the Givis.
Mike
Honda Forza 350 - Adso
Honda Vision 110 - Bright "Ignorant people will always be afraid of what's different and will always mock what they don't understand."
Capitano
Proud to be a member of the Ugly Bunch
From past experience, take a good look at the Honda box, and see if it is made by Givi or Shad.
My Suzuki Burgman has a Givi box which is exactly the same as the Suzuki offering for less.
I have a selection of Honda boxes, as I always take them off and fit Givi boxes that I have. If you just want another box, pm me and I'll see if I can help
If you're going down the Givi route, note that the earlier models use different fittings. You will struggle to just attach the Givi plate directly to the Honda rack (was this deliberate on Honda's part?) The 2023 onwards model is MUCH easier to fit (it uses the same rack fittings). The Givi boxes are better shape, I've got a Givi B45+ on the Forza, and a selection of others in the garage.
Leadfarmer wrote: Mon Apr 13, 2026 11:10 am
What do you mean when you say it’s broken?
I had the smart top box which wouldn’t open after I moved the carrier to change the coolant
The operating cable had come adrift, my dealer fixed it for free
Otherwise, Givi do a E251 universal mounting plate that can be fitted to almost any carrier
Yes, it may be possible to attach the Givi mounting plate to a non-Givi rack, When I lost my Yamaha Tmax mk6 Topbox (Yamaha rack and box - still don't; know how I lost it!), it was possible to attach a Givi mounting plate like that to the Yamaha rack - its just a case of bracketry and bodging (I hasten to add that my local workshop did this not me). Then any Givi monolock box can go onto the plate. That is an advantage of Givi's system, once you have a mounting plate any box of the right type will fit on.
I bought Shad kit TOP H0FR15ST for my ADV350 for £40 on Ebay last year. This was listed as suitable for Forza too but you should down load the fitting instructions on the Shad site. It provided a steel flat plate in two halves and this would accommodate virtually any composite plastic mounting plate although drilling extra holes may be needed. The steel plates are heavy gauge so drilling may be hard work if you are not used to it or don't have the right tools. I change bikes too regularly and have done this quite often.
Located on UK South Coast
Honda ADV350, Honda Supercub, Honda CT90, Triumph T100R. Previously SYM Joymax 125, Honda CB300R. Silence S01, Kymco AK550, Triumph Tiger 850, Triumph Street Twin etc...
Having read the OP’s post saying the OE top box on his Forza 350 is broken due to the terrible roads round here in the UK is frankly ludicrous.. My 15 years old Givi top box is still in better condition than I am 15 years older.