SIP Performance it does exactly what it says on the label. It has been the most popular large frame tuning exhaust system for the last 10 years. Jim Lomas, himself active as a racer in the 6T's, began in 1979 to produce performance orientated expansion chamber exhaust systems for two stroke motors. Due to the enormous demand from the scooter scene revival of the day, he soon decided to concentrate his efforts to the enhancement of the VESPA and LAMBRETTA scooter ranges. The later emerging German and Austrian street racer scene were in need of a pipe that could be used for maximum power and rev range setups, with an especially voluminous expansion chamber for low to mid range torque delivery. In 1997 we combined our strengths with Jim's and developed the SIP Performance expansion chamber system: loads of oomph from way down the rev range, stainless steel construction, allows the use of a main stand and wide tyres. Over the years this system has been constantly improved and updated and sadly (badly) copied.
This exhaust system is hand finished in stainless steel. It is also available with a polished finish. A double walled construction in vital places ensures less noise output, increased solidity and an eye catching rust free design. It is mounted to the motors exhaust stub manifold using springs. The main exhaust mounting bracket is robust enough for the stress and strain of normal daily use. We decided against the use of O-ring exhaust gaskets to enable sufficient flexibility and so reduce danger of the pipe being cracked or otherwise damaged. This exhaust system can be used in combination with OE PIAGGIO cylinders and virtually all states of tuned motor setups, from mildly tuned road going scooters through to maximum power projects. A broad power potential can be realised from 15 PS through to 28 PS, enabling potential top speeds of between 105 and 150 km/h (62 – 90 mph!).
The other exhaust in this range, the SIP EVO Racing exhaust is almost identical to the SIP Performance exhaust in construction, differing only in that the EVO is constructed using normal (non stainless) steel and powder coated. There are two versions of this pipe available for the VESPA T5 models. The unit including the shorter downpipe manifold is suited to the more higher revving motor setups. It is especially harmonious in combination with the OE PIAGGIO 125cc cylinder. The SIP Performance NT represents the version with the longer downpipe manifold section. This unit ensures power delivery in the lower and mid rev ranges and so lends itself ideally to MALOSSI or POLINI cylinder setups.
JL Guarantee: Included with every SIP-Performance expansion chamber system is an automatic JL Guarantee for all original purchasers, if your exhaust splits open at any time during normal use (apart from grinding it along the curb) it will be repaired or replaced.
Conclusion: A completely convincing sound and performance. The SIP Performance expansion chamber system is suited for the more milder road going scooters and also maximum power tuning projects.
Racing expansion chamber/ stainless steel or steel construction, black powder finish/ stainless steel silencer/ left hand exit
Stainless steel/ steel, black powder coated finish, hand welded multi segmented production, stainless steel silencer, left hand exit
These exhausts allow the continued use of both the main-stand and wider section tyres are also possible.
Carburettor jetting and ignition timing should be checked and/or adjusted for reliable and enduring use of this exhaust system.
SIP-TIP: In combination with 139-177cc kits a larger DELLORTO SI carb. of 24mm and a taller transmission ratio are necessary for a more harmonious and optimised set up. Near standard OE PIAGGIO 200cc cylindered motor setups will require a main jet at least 10 sizes larger for the OE DELLORTO SI 24mm carb., a MALOSSI 210cc cylinder along with a stronger clutch system (COSA clutch), a modified cylinder head, a VESPATRONIC ignition system and last but not least a longer stroke crankshaft is advisable. A 30 to 36 mm reed valve carb. system should take the motor up to the 30 PS mark.
SCOOTERING Quote, England, „exhaust test“: “Let´s take a look at the performance diagram: Bingo Bongo! 18.3 horsepower at 6,840 rpm as well as 19 Nm from 6,200- 6,800 rpm! The characteristics of this exhaust are similar to the PM Evolution, whereby the SIP is a good deal more elastic. The power curve flies through the whole range of revolutions up to the maximum of 18.3 horsepower. At 5,000 rpm there´s still 10.4 horsepower as well as 15 Nm packed in the back tire. Very good for daily street use, very good when doing wheelies down by the bus stop. The SIP Performance impressed us with it´s elasticity, it really stomps on it! Our highway test was also impressive - at 140 km/h maximum. The sound and the material used in construction is worth stealing for....”
Worb5 Quote from the “PX exhaust review”. “27.5 PS @ 7620 rpm and 26.9 Nm of torque @ 6860 rpm. JA! Once again a winner. Performance, torque, the rev range to match and as wide a power delivery as you could wish for! It tops the PM EVO by 300 revs, great exhaust.”