bit of a boost?

[wisebeuy]

Ok, I'm sick tired of wanting that bit of boost needed while overtakin/going into wind/uphill and want to do something about it. As far as I see it, the only way I can do this without rebore is either

fitting a nos kit, which (besides illegal and a bit over the top, ) is expensive, but does anyone out there know how to bodge one or get a cheap one? There is no doubt in my mind I will have one some day, it would be the most awesome thing ever!!! All that extra power at the push of a button!

or put some sort of booster in fuel, like octane booster or something, but will this really make a noticible difference?
Got an XLR 125R by the way.

[G]

These seems a distinct case of a 'buy a bigger bike' advice moment.

However, instead I will suggest you go to here for instructions on how to 'do it yourself'.


Sorry, but....
Buying a bigger bike will probably not only come out cheaper, but mean a more reliable bike, much more power if you want and I'm sure you would enjoy it a lot more.
There isn't many cheap ways of getting a decent amount of power from a low power as standard 4 stroke 125. Most of them cost a lot more than selling it and buying a bike with more power in the first place.
You are also likely to devalue your bike quite a lot, one way or another.

Only time I can see it's really justified is either on 1000cc+ bikes or maybe on slightly smaller where you may want the occasional boost to say keep up on a track day.

I wouldn't mind playing with NOS on a small 4st... but I wouldn't want to do it on one that was worth anything.

[mr jamez]

A switch to a two stroke 125cc would be a more sensible and realistic option than Nitrous oxide on a 125 4 stroke, would probably blow it up

[loply]

yeah you could just as easily go out and buy a more powerfull bike...

will give you a lot more power than a nos kit. and be cheaper.

[Kickstart]

Hi

A NOS kit would cost a load of money (but I can see no reason why it would be illegal, although your insurance company might well freak).

There used to be some big bore kits available for the older XL125. Failing that not sure it the top end of an xl185 would fit.

All the best

Keith
____________________
Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[RS1Banger]

just sell it and get a 2 stroke 125

they have double the power (if derestricted)
also double the fuel consumption
and half the engine life
at least twice the fun

Or, some years ago I knew a lad who bored out an Honda SL 125 (1974 trial bike) to the limits of its cylinder, worked out as 170cc ish.
He then took his old piston and the newly bored barrel to the local bike shop (Rojos), they fitted it up with a piston off an old CB750.
I don't know if I would recommend this to you, but it is possible.

[yohomiesmelly...]

I think 2 stroke motorcycles create 1.6 times the amount of power that a 4 stroke motorcycle does.

I can image the conversation when speaking to an insurance company about fitting NOS to a vehicle.

Motorcyclist: "Hello I would like to declare a modification i have made to my vehicle"

Insurer: "Yes sir could you state the modification you have made?"

Motorcyclist: "Ive fitted NOS to it "

Motorcyclist: "Hello?"

Motorcyclist: "Hello?"

Motorcyclist: "Hello is anyone there?"

[Ste]

Having NOS fitted on the roads is perfectly legal, it's illegal to use it though.

[mchaggis]

What about engines running on Avgas, methanol or lpg? Are race-tuned engines running on special fuels allowed on the road so long as they are in a road legal vehicle otherwise? And what about the jet bike of such fame? I know it's not really practical to have turbojet powered road vehicle in anything much smaller than a truck, but are they accounted for? I can only assume this is covered by the SVA regulations. (Single Vehicle Approval test to get a certificate of conformity).
____________________
I must not be a troll...
Mmmm, Guinness
Discovering the delights of Hammerite and a 3/4" brush.

[Kye]

"NOS" branded kits are dangerous on small bore engines running low BHP jets, since they are jetted at point of injection (e.g the carb manifold), and when the solenoid opens up, there is a delay as the nitrous fills the line in between the solenoid and point of injection/jet.

The dangerous part is this line acts as a resevoir, and thus, once you release the magic button, it will still be injecting nitrous oxide into your engine as the line will still be full. This isnt a problem on bigger boost setups, since it uses it quickly but on a small 125 with maybe a 7bhp boost, it will take a while to use it, and you may come into a corner or worse when it is still on.

[Kickstart]

Hi

I cannot think of anything that would make a nitrous kit illegal to use on the road.

[Kye]

Actually avgas will help power, due to the massive lead content, plus taking advantage of the octane with extra compression does help.. a lot of race bikes run 60/40 petrol to avgas so it'll pass the sniff test in scrutineering (right until they start it on the race track )

[Kickstart]

Hi

Only help if you modify the engine, and I suspect will cause major problems if used neat. Likely to still be burning past bdc.

All the best

Keith
____________________
Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[sickpup]

Nitrous is legal to use on the road. Its a catalyser not a fuel.

Avgas and Methanol are illegal to use as fuels as they are not VAT rated for road use.

Methanol can possibly be used as a fuel multiplier, this is a bit of a grey area.

Race engines and turbojet engines are legal on the road as long as they are run on legal fuels.

Would someone please explain why they think Nos is illegal?

[kev]

Well speaking as the only forum member I know of who has ever had gas on their bike, I will just give you a couple of facts.

1 it is very illegal to use gas on the road due to the way the power is delivered.

2 it is perfectly legal to have the kit fitted and primed.

3 you can use it on small cc bikes and the lines wont take ages to empty.

4 its very over priced and very over rated.
____________________
20:02:36 Jammy-R6: any holes a goal
20:02:48 kev: even if its a hairy mans arse
20:02:56 Jammy-R6: hell yes

[sickpup]

[mchaggis]

[RS1Banger]

well bikes don't do emissions test for mot do they?
so nos must be ok?

[sickpup]

The most authorative site I can find for Nitrous is Burgerman's...

https://www.diy-nitrous.fsnet.co.uk/motorcycle-nitrous-injection-system.htm

This even includes a list of insurer's to insure your new N2O powered bike.

[G]

(ahem), see the first reply

[sickpup]

[Dom_]

I belive N2O is not illegal to be fitted, but to use it on a public highway would be illegal.

Also, fitting N2O on a 4 stroke is a lot safer than fittin N2O on a 2 stroke.

And finally NOS is a make, just like sony, HKS and Akrapovic.

its name is Nitrous Oxide/N2O

[Kickstart]

[sickpup]

In response to Youngun'

1. Why is it illegal, i.e. which law?

2. Really. Done much testing or can you quote some studies please so I can have a look please. Not saying your wrong just refuse to blindly accept your right.

3. Yes it's a generic name just like Hoover.