Exhaust made it slower

[Wilson123]

https://www.pmtuning.co.uk/Merchant2/merchant.mvc?Screen=PROD&Store_Code=PT&Product_Code=01-ENTB_503&Category_Code=00214100SPEEDFIGHT

So I fitted that to my peugeot speedfight 100, it has a K&N air filter on and that's basically the only 'modification' I've done

It's considerably slower speeding up, it feels like it's not getting enough of something or too much of something

Top speed went up by about 5mph as I just blasted it down a hill doing 73 oo-rah

Any ideas on what it could be?

[stirlinggaz]

hi,
perhaps it might be an idea to look at the jetting?
if youve upgraded the exhaust & airfilter, youve messed around with air/fuel & will pobably need a bigger main jet, to let more fuel flow at full throttle.
cheers,
GAZ

[Vincent]

Yup, there's a good chance you're running too weak at present and could melt the engine
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Space Is Deep

[Wilson123]

Yeah I thought it was the jet :l but it's hard to find out my standard main jet size

So far 72 and 81 are the closest I've come

[Kickstart]

Hi

As above.

However most exhaust will lose you power in one area to gain it in another. With a normal bike you just change gear to make sure you are at the rpm where the power is. With a scooter you might need to play around with the weights on the clutch to get it to allow more revs at the same speed (ie, not lock up until a higher speed).

Plenty on here know WAY more about scooter transmissions than me so hopefully one of them will be along soon.

All the best

Keith
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[Wilson123]

I got some rollers with the exhaust but I didn't fit them, I'll have to fit them and see how they go

[greenman]

raise the needle in the carb 1 notch if it runs a little better ,you need a bigger jet ,back of thrashing it because its running weak

[ms51ves3]

[Wilson123]

Fitted those rollers earlier, 6.6grams and it's fucking rapid!

Still does 65 on a straight even with the lighter rollers

I took the silencing shit out of the exhaust too so it sounds evil!

I didn't have time to fuck around with the carb so I'm ringing PM Tuning tomorrow and seeing which jet size they recommend for my bike with it's components

£80 well spent

[The Artist]

How about you STOP BULLSHITTING about your frickin top speed tard

[Wilson123]

Yes because my idea of a good time is lying about the top speed of my moped

Fucking idiot

[lukamon]

[Wilson123]

Lmao

Finally someone with a humorous side

I liked that

[The Artist]

[Wilson123]

Not really lol

Better about what? On my bike I'd be able to beat any car in a race and I'm not old enough to get an over 33BHP bike so I'll stick it out until then

Do you have a 50 or something? What are you crying about?

[The Artist]

Just the sheer amount of people on here (ped owners) that claim to have stupidly fast peds doing unreal speeds with multi coloured powerbands and nitrous.

I had nitrous when I had ped and it worked for about 5 seconds before all the seals around the crankcase popped out.

[Wilson123]

Lol I don't have NOS

I have a standard peugeot speedfight 100 '07 plate with the exhaust listed, 6.6 gram rollers and a KnN air filter

It does 65 on flats and 70 down a hill :l Had it to 72 on the moores(sp?) stock

[Wilson123]

And lets be realistic, 65 isn't fast.

[baldy]

You may not have to up jet the carb, it depends on the exhaust. When my brother fitted a k&n and sports pipe he didn't need to change the jets.

[Wilson123]

It feels perfect now but do you think a bigger jet will make it run sweet and get more petrol it?

[baldy]

if you take the sparkplug out the end should be a coffee brown colour. If it's black it needs a smaller jet, if it's white or grey it needs a bigger jet. Post a pic of the plug and i'll tell you what jet you need.

[Wilson123]

Yeah I've got a picture scale of spark plugs

Recently it was a coffee brown, it's an iridium BR9IEX sparkplug, I was using the standard NGK 8 spark plug and it wasn't working properly so I tried the BR9 and it sorted my problems

I'll have a see

[stevo as b4]

My std SF100 did what i belive to be true 54mph on the flat, using a trip computer as my verification. The indicated speed is 56-58mph, and downhill it would indicate 63-65mph, but really only about 58-60mph.

You definately needed the lighter rollers, and depending on the pipe, stronger clutch springs too. The jetting will never be perfect with any aftermarket pipe, and so re-jetting is always a good idea, if you know what your doing. I find scooters hard to set up personally, so id pay to use a dyno every time tbh.

Whatever you do don't change the Variator to a Malossi one, as they are no good at all on the 100cc.
Keeping the std carb, is also best i think on this motor, as if you go bigger you lose power and acceleration, for a tiny gain at the top. The engine's don't tune very well, so after a good pipe and set up to suit, it's best to call it a day! I'd have been happy with this set up and the VFM/ expense to power gains involved.

I found out £600 later that 11.8bhp was as much as i could get out of the motor, and the only mod left was a 120cc kit that might have added another 1-1.5bhp at the most. At the beginning i was thinking id get an easy 15bhp out of it, but i just ended up looking a tool tbh!

[Wilson123]

Thanks I was heavily considering getting a malossi variator too

I'm also heavily considering a 120cc bore kit as my exhaust fell off due to piss poor handywork and tore one of the thread things out

When I get time I'll find out the size of my original jet, does it say it on the jet or something?
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[SoND]