So, I have a 916 biposto engine in standard trim running on a 1.6m ECU. Currently I have the standard exhaust system on the bike, but have a pair of arrows 50mm slip ons and the link pipe in need of rebuilding. When it comes around to it, I’m looking to get the engine out of the frame and give it an overhaul as it hasn’t turned for eight to ten years. I may indulge the engine with a new free flowing filter and bit of headwork and possibly high compression but that’s it. So my question is this; What exhaust system is best for this level of engine? Speaking to Rich at Louigi moto and Brad Black, they both say to stay away from a full 50mm+ system unless I’m playing with 996+ engines. Brad seems to think even the 45-50 link piped system leave a bit of a flat spot in the middle of the range and advises 45 slip-on on a stock to mild 916. Rich says that they actually respond reasonably well to 45-50 half systems and a bit of tuning – nothing excessive and in line with what I have in mind for the bike. In terms of the ECU, I’m tempted to not replace the chip until I’ve been to Rich or A.N other with it and let them do the road work, as I understand that the performance eproms did nothing other than flow more fuel. There are several Ultimap chips for sale on the bay, but none of the UM181 which Brad recommends as being right for the Biposto running 1.6m and a slip on silencer. You’ve all no doubt played with most engines and exhaust configurations, so your real world experience please gentlepersons.
Sev, for road use stick with the 45mm front end and just go 45-50mm on the cans, better filtration with a careful set up by Rich and then a full ecu reflash by CJS. You can get quite a bit more that way without any porting, compression and valve work but what you will notice the most will be the extra torque, smother running and a much nicer engine at normal road speeds.
I believe Chris (CJS) is currently the only person offering the service of mapping and writing a new EPROM to suit the half system (45mm headers to 50mm end cans). The 1.6M and P8 engine management systems are very old technology now and IIRC, the software used runs on a version of Microsoft from the 90s. I agree with DTD, the half system will give you a nice bike to ride on the road. Andy
Splendid. Its way more bike than i am a rider so just big road torque dollops and car alarm igniting soundtrack will do fine as i pull up for a lar-tay at my local schmooze pit.
