Hi guys, I have a few questions about the 916 lump in my ST4 project, basically i would like to rev a little more freely (without going loopy and diving inside the engine to lighten and balance things just yet). I believe that the flywheel on the ST engines is a heavier item than on the sportsbikes for smoother cruising, is it a simple swap to stick a superbike one on or will i upset the engines balance if i do that? on this subject purely for looks i would like to run an open clutch, i've seen plenty of coloured anodised pressure plates which will fit but are they all equal? its just a slab of machined aluminium but do some fit better than others? in an ideal world i would love a slipper clutch but its not in the budget at the moment... I will be running a totally open intake (no airbox with filter socks on the trumpets) and it looks like a MADASL spaghetti exhaust, i take it the stock ecu can be mapped to take this into account? i don't see many people running power commanders so i assume this is ok? without going internal on the engine (that will be done but not in this first phase) is there anything else i can do to help it to spin up more freely? Cheers Rich
Hi Mate, I notice that you're in Bristol, so the best advice I can give you is to speak to Rich Llewellyn at Louigi Moto (Clutton Hill). Extremely knowledgeable and helpful Ducati specialist. What he doesn't know about tuning Dukes probably isn't worth knowing and his advice is free! He rebuilt my ST4 engine when the main bearings went and advised me to have the crank balanced at the same time, which did indeed allow it to spin up much more freely and was well worth the £140 extra. Miss my old ST4, it was a fantastic bike which is very underrated.
The 916cc engine's flywheel is just a weight, there is no pickup in it so you can remove it completely. I don't know if it's heavier than that on a 916 (sportbike) as that's a heavy blighter too. I replaced the flywheel in my 916 with one made to the same dimensions but from aluminium rather than steel, it's much lighter but in hindsight I'd probably remove it completely as there's plenty of weight inside the engine to keep it spinning...
Cheers guys, I'm not sure about removing the flywheel entirely, it would probably be fine but it makes me nervous lol I will look into an aluminium flywheel though I will pop over and see Rich at Louigi Moto at some point, i know Mark at madasl has some close ties with him and cjs so i will have a chat to him too when i drop the bike off on saturday, although last time i talked to him about the engine he tried to talk me into fitting a long stroke crank with 998 barrels and pistons :biggrin:
