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Mar 13

Posts: 1

Toner400F says:

33bhp restriction issue

Hi all,

I have an issue regarding the 33bhp restriction for a motorbike.

I obtained my full motorbike license before the new regulations came into effect in Jan 2013, so I am restricted to 33bhp for 2 years.
I have access to a 1976 Honda 400Four, which when new was claimed to have 37bhp. It is highly unlikely that the bike is still putting out more than 33bhp.

I don't want to pay the ridiculous prices for a restriction kit as it won't change the bike's performance at all. 

Do I have any other options or will I just have to deal with paying for a restriction kit to ride the bike legally?
I have considered getting the use of a dyno but the results can vary from machine to machine, so the power output shown may not be useful.

Any help with this matter is greatly appreciated,


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  • Posted 2 years ago (14 March 2013 20:54)

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Aug 09

Posts: 2707

MarcusMarsh says:

33BHP Restriction

This topic has been covered quite a few times on this forum. 

There are various opinions as to whether you have to prove the bike only puts out 33BHP or if the Police (or insurance Co as the case may be)  has to prove that it does not in the event of an incident.

For a start put it on a dyno.  Power outputs in those days were often inflated or measured under absolutely ideal conditions by manufacturers as it sold bikes.  (Maybe it still does!)  It is quite possible that your bike is within the limit.      

[This Reply has been modified by the Author]

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Apr 08

Posts: 3042

AdieR says:

Get it dyno'd

but don't forget there's also a power-to-weight factor too (0.16kW/kg?).

A bike that old (as far as I know) pre-dates the 33bhp rule (1991?), so you might not come across a 33bhp kit all that easily anyhow.

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Mar 10

Posts: 1032

bmwgs says:

just make you own kit if you need to

best put the bike on a dyno and see if the bike has lost some bhp. as you can make your own kit for it  was long as its 33bhp at the rear wheel you be fine.

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