2 cyls or 4 cyls for A2 restrictor kit?

[TravisBickle]

So my son gets back from Canada soon and will be in the market for an A2 bike (he is 19).

I'm trying to steer him towards an A2 bike with the logic that he'll want an upgrade by the time he's 21 anyway so don't really need the faff of restricting the bike and proving it to the insurance company in the event of an accident, plus having the temptation to remove it etc... but he seems quite keen on getting something bigger to restrict to A2 (something around 600cc to 700cc) I think mainly for bragging rights to his mates, but we were all young once! So do I get it, if that's what he wants to do, fine.

Question is, if he does end up getting something bigger, would something like Honda's I4 650 seem a bit gutless once restricted in comparison to something like:
Kawasaki's I2 650
Suzuki's V2 650
Yamaha's I2 700
?

Or would having the extra cylinders in the Honda give a better/sportier riding experience for the top end screaming revviness?

From my understanding, in a VERY broad and generalising sense, engines of the same displacement and in relatively the same state of tune:
Fewer cylinders = more torque and less power, less happy to rev hard
More cylinders = more power and less torque, more happy to rev hard

I know whether it's inline or V can have an impact on engine characteristics as well but I think generally, number of cylinders is the biggest factor?

The offerings from the big four all put out almost exactly the same amounts of torque. The two cylinder offerings from Kawasaki, Suzuki and Yamaha all produce roughly the same amount of power but the Honda is significantly higher than the other three.

So question is, once restricted to 35kw the power output is irrelevant. But we're wondering whether basically the Honda 4 cylinder would be feel far less punchy than the other three through having far less torque after being restricted (because it's had to be restricted more than the other three because of its higher power output)?

OR would it be fair to assume that all four would actually have pretty much the same amount of top end performance due to the power limitations, and the Honda NOT feel less punchy at all, and actually having a more rev-happy Honda could be a bonus?
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2024 BMW M1000XR
2021 Honda CMX500 Rebel S
2016 Triumph Tiger 1050 Sport

[ThunderGuts]

I think some (all?) restrictor kits restrict the throttle movement/range rather than the power directly, effectively lopping some of the end of the throttle off. If this is the case, then those bikes are going to suffer reduced performance across their rev range and it probably won't make much difference, but I'd imagine a relatively low power/low capacity IL4 that's restricted will be pretty wheezy low down.

Why doesn't he get an A2 bike that's relatively punchy instead? The regs around A2 are focussed on power, not torque or capacity (although the rules are different around the A2 test bizarrely). I imagine a bike with a larger, torquey engine but with A2 levels of power will feel much quicker in the real world, even if in reality it probably won't be and quicker than a strangled 4-pot.
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TG.

[xX-Alex-Xx]

[Polarbear]

A restricted bike is never going to be as good as a bike designed and built to be at it's optimum for a certain power/size.

I suppose if he has his heart set on a certain bike that can be resticted all the sensible ideas go out the window with most yongsters. WHy have a CB500 or equivalent when you can have a (restricted) Striple or similar?
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Triumph Trophy Launch Edition

[TravisBickle]

Thanks guys you've all pretty much confirmed what my uneducated logic was indicating.

I have had the conversation with him about just getting an A2 bike as like you have all said it's designed for that size and weight bike rather than restricting something bigger... but he seems to think the CBR650R is actually lighter than the CBR500R. Haven't actually confirmed that myself yet but doesn't sound right unless the bigger/bettermore expensive bike is made with lighter materials.

So yeah I'll try to steer him towards an A2 but if he does go for something bigger I'll suggest the Honda would be a poor choice.

Thanks.
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2024 BMW M1000XR
2021 Honda CMX500 Rebel S
2016 Triumph Tiger 1050 Sport

[Kentol750]

An a2 bike cannot make more than 0.2kw per kilo, so if it's bang on 35kw it must weigh no less than 175kg. As said above, a standard a2 bike is better than a throttle restricted 94or less bhp bike. Sv650 post 2016 is done by ecu and unless you push it, it's not that noticeble for every day use. A lot of newer a2 compliant bigger bhp bikes are also restricted electronically and some can be flashed to full power upon production of a full A licence.
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Some bikes.

[struan80]

A cbr650r is a great bike, until you try a Fireblade. Had the 650 a while back as my first bike. To be honest I actually preferred the Hornet I did my DAS on. An earlier CBR600 would be the better and cheaper option for your first bike.

And I like my CBR's

[TravisBickle]

[redeem ouzzer]

Ha ha ha at your son’s age I had a REAL MAN’s bike, GSXR750L, Yoshi pipe, dynojet kit, +1mm overbore. Genuine 116bhp at the wheel. Fuck all that 35kw bollocks! Wait while he’s 24 so he can do direct access and get something that will pull the skin off a rice pudding.
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Be a REAL MAN!

[Kentol750]

Get him through asap and he can then go full A 2 years later. So fireblade at 21 and a bit.
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Some bikes.

[TravisBickle]

[xX-Alex-Xx]

[TravisBickle]

Thanks for your concern/interest!

They said they stripped the engine and found evidence of rider error.

Laughable!

I don't think this came as a shock to anyone.

Just sent them an essay and giving them 28 days to pay up or go to court.

I'll keep you posted in the other thread.
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2024 BMW M1000XR
2021 Honda CMX500 Rebel S
2016 Triumph Tiger 1050 Sport

[TravisBickle]

[SpiritMr89]

Did they ever change the laws?

Used to be:

'If a restrictor is fitted, anywhere it is legal.'

My little 650 had the throttle stop 'come loose' and my mates SV had them fly out and stuck under the grab rail.
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Hello

[redeem ouzzer]