Upgrade to more then 125cc in the UK

[kramnala58]

I have a question for our UK members ....

I understand with your licensing that with the L sticker you cannot ride anything more than a 125cc motorcycle. But if you install a big bore kit to increase the motor to 165cc or 175cc (or whatever the big bore kits are), are you able to operate it with only the L sticker?

Additionally, do you have to declare with the authorities (whoever they may be) that you have increased the size of the motor?

[iceman]

if you change the performance of the bike in any way you are legally bound to advise the insurers of the change and probably face hefty premium increases - also any major colour change of most of the bike needs the DVLA (road licensing authority) involved to change the vehicles registration details.

Many people will make changes and not tell anyone but it invalidates the insurance should you have an accident and they examine/inspect good enough to notice. Even a louder exhaust than stock is technically illegal here!

The L sticker, or more accurately the CBT or A1 licence limits the CC size of the engine and/or the horsepower - many 125's can be adjusted to give more HP than the provisional CBT (L plate) allows so even then is illegal.

[BPT7594]

Illegal.
Europe is very strict about these things. Best you can do is upgrade and wish you don't have problems with it.

[Robbie]

Best thing is to get an unrestricted licence and ditch the L plates.

[JaeMelo]

If you have a 125cc and want to throw on a bigger cylinder kit it is technically illegal but no one enforces it. They would have to randomly strip down your bike down and measure your bore to enforce it so you're fine. When it comes to getting you bike emission/inspected simply throw in your stock rollers and stock exhaust if you changed either and you'll pass on the dyno without an issue with these Yuminashi kits. Anyone who has messed with scooters in the UK and here in Bermuda will tell you the same thing. This has been done for years and hasn't changed a bit... To make things even better for these bikes in particular Yuminashi uses stock 125cc blocks and simply re bore/sleeve and resell them as 150, 165, and 175cc; so from the outside appearance no one will know or can possibly know it is oversized. The block makings still say 124cc and that will be assumed upon inspection.

Now if for what ever reason if you go from 125cc to something crazy like 210cc or 150cc to 300cc like on the SportCity's then you will fail the dyno test regardless of roller weights. That I have heard happening here in Bermuda.

[chicaboo]

Do they do an emissions test for the MOT, or just a sound test?
Because if you are tuned to 12.8-13.3:1 AFR or something for max power, I don't think you'd pass.
Putting the stock exhaust back on a tuned scoot might cause an even richer fuel mixture?

[BPT7594]

Remove the fuel controller then.
Yuminashi controller has 2 dedicated wires. Plug them together and you removed the controller effectively.

[JaeMelo]

Do they do an emissions test for the MOT, or just a sound test?
Because if you are tuned to 12.8-13.3:1 AFR or something for max power, I don't think you'd pass.
Putting the stock exhaust back on a tuned scoot might cause an even richer fuel mixture?

They don't do emissions on scooters here. Possibly on cars but definitely not scooters or at least not here in Bermuda. I wonder how they'd even get it done with the exhaust tips being so tiny on factory 4T scooter exhausts?! On cars they usually put a wide band o2 on a special exhaust clamp that looks like a pair of pliers except it houses the o2 and clamps onto a cars mufflier tip.. Not sure how they would get one of those on a bike...

[chicaboo]

In that case it's unlikely they'd not pass you with a bbk if you have a stock exhaust for the test.