Scorpion pipe?????Got no sting.....

[bogey]

Have always been a little suspicious about performance from certain aftermarket pipes on most vehicle types. After selling my LML which came with a Simonini then I fitted a Scorpion exoansion chamber then back to stock with cat to sell I was a quite impressed how much extra low end torque the Scoot had. Well as I replaced LML with a PX I carefully ran bike in to 1300km then fitted Scorpion pipe back on. Re jetted to 100 main and fired it up. Throttle is really smooth no hesitation or flats, really nice. But suprisingly has lost its low end torque, really needs thrapping to get it to pull. Is this normal at the expense of bottom end power, is it worth going down a size on the main?

[bryno]

That's normal for an expansion pipe, the PM Tuning (similar looks to the Scorpion) is the same, huge improvement in top end pull, huge loss of bottom end torque, on my T5 it was hopeless unless you like running at 7'500+ everywhere.

Rejet won't make a difference, it's just the pipe design..

[bogey]

Are the engines ok for so much stick? Ie thrashing around all time?? Must agree around the top end is much better, has been a little difficult to tell due to the high winds round here lately. It just seems if your going slightly up hill it pulls really well to around 45 on the speedo, shift to 4th and it slows, don`t know whether to thrash a bit more but not sure theres much left

[mickey movistar]

all expansions are the same
i have a spaq pipe (scoot rs type but better lol) on mine px200
will pull to 62 on speedo in no time through 1st 2nd and 3rd shove it into 4th and there seems no difference takes a while to get to top speed
uphill its hopeless it goes faster in 3rd lol

you have to rev the arse out of any expansion chamber
mines done about 10000 on pipe
full revs all the time
the vespa can be thrashed without too many worries

[bryno]

Agree with that, can't speak about the PX motor, but on the T5 with a stock motor and an expansion pipe in many situations it actually goes slower, i.e. hills, into wind etc, it struggles to break out of the flat spot unless you are constantly dropping it down a cog to get it into the rev band...

Which is why I junked my PM pipe, too much like hard work!

[bogey]

Well the wind has dropped today and does seem much better. Get to some hills though and speed does slowly go down. Sure it would work much better on a tuned motor though with a bit more torque to it. Gonna save for a BB kit I think now.

[james]

Same with my pipe. You forefit low down power for top end power. I live in hilly Devon so tend to stay in 3rd!!!

[bryno]

bogey said:

Well the wind has dropped today and does seem much better. Get to some hills though and speed does slowly go down. Sure it would work much better on a tuned motor though with a bit more torque to it. Gonna save for a BB kit I think now.

It will, my PM pipe was much better when i ran a Malossi 172, it gave it the extra torque at the bottom end.. was just pants with the stock 125 IMO

[Smallframe]

If you take P2 with a scorpion or SIP type expansion chamber, it will rev out a lot higher when permitted to by the gearing. This ability to rev is governed by the length and taper of the header pipe and overall size of the resonance expansion chamber. A lot of vespas experience a large 3rd to 4th jump and a subsequent drop in the rev range, taking them too far out of any potential powerband ( T5 can be an exception here).

Port timings on standard barrels and size of transfer areas can't really take advantage of proper expansion chambers. However if a T5 or shorter4th gear is fitted then this power loss is greatly reduced and whereas your scooter may appear slower on a gearing calculator (ie reduced top speed in 4th) , in the real world of headwinds, hills and 2up riding, the motor will actually pull better and create more power.

GOOD GOD I'VE EVEN MANAGED TO BORE MYSELF

[bogey]

Yeah 4th gear is a cop out. Is it a big job to change the 4th gear ?

[bryno]

Ah, right.. I always presumed T5 gearing was longer than the P2, so with T5 4th, a P2 is going to be reving higher at same speed..

And a Cosa clutch does the opposite and extends the gearing in all gears?

[bag5y01uk]

Hi interesting read, Im currently doing a trial for B Race tunings new vespa pipe, left hand side, mild steel, no sparewheel capacity. What can I say this pipe is the dogs dangleys!!! forget T5 fourth gears for a P2 use a Dominator exhaust they have bucket loads of torque, (if anyone has seen the results of the scootering mag lammy exhaust test you'll have seen the quality of the work )
Mine is the new 125/180 version and on my polini kit it flys dyno graph prior to the exhaust being put on 17.5 BHP if it isnt another 2/3 BHP more I'll be astounded. Ask anyone who has a B Race pipe and they all say the same thing, THE BEST THAT MONEY CAN BUY I'll get some pics of the exhaust on here in the next couple of days(its dark out now) But this is a pre-production pipe at the moment and I know a few people who have put there bids in already.
Cheers ...

[joey]

Aren't there a few concerns over the weight of the mechanical muffler on the B Race pipes?
I've read elsewhere that they are good for power etc but not the lightest of pipes, that and the fact that you can't fit a spare?
Still, mild steel has the edge over stainless whatever way you look at it ;D

[bag5y01uk]

Yes there have been concerns over mech mufflers mainly dating back to 80's, the new pipe is an absorbsion muffler tho, although to be honest id prefer mechanical. With regards to overall weight well look at it this way, if its light then its thin, which having looked closley at scorpion stainless pipes im not really suprised that they crack. These pipes are built to last not to be replaced on an annual basis.
And last but by no means least, the spare issue. Well its an individual choice of course, but i carry a spare tube and small gas CO2 cylinder, less weight than a spare, so your light exhaust and heavy spare kind of cancel any weight arguement.
At the end of the day its a quality product, and if you speak to B Race you get honest advice, unlike some other dealers/manufactuers .

[dave1967]

Hi
Can someone post conatct details for B Race,

Cheers Dave

[mickey movistar]

googl it
i found it that way

[Lucia]

www.b-racetuning.co.uk/contact_us.htm

[bag5y01uk]

Finally let me back in, now i cant post the pics of the exhaust!!
Any ideas how?

[morphinemitt]

My mate put a scorpion pipe on his GT200 and found the ONLY benefit was cars could hear him a lot more than with a standard pipe.
Very disappointing

[mickey movistar]

i must agree it is quite reassuring that other rd users can you hear you a bit more clearly

so these things do have there ups lol

[jase]

I had a Scorpion on my GP200 a while ago and it was the worst pipe I've ever had, 4th gear was rendered useless.
I had a PM pipe on my P2 and that flew, the engine had an Autisa 200 top end, would sit comfortably at 78mph and pull in all conditions.

[Lucia]

bag5y01uk said:

Finally let me back in, now i cant post the pics of the exhaust!!
Any ideas how?

Sorry I'm late, I've just spotted this - I've PM'd you - hopefully it'll make sense