jimmy Posted January 22, 2010 Report Posted January 22, 2010 Hey! I've got myself an Aprilia RS250 track bike which i'm in the process of getting ready for a season of trackdays. It was tatty when i got it hence the winter project. I'm also going to beat my mate on his RGV250! Anyway, i'm after some info about the power valves. Now this may seem like a really stupid question, and it probably is! But can i remove or have the power valves on constant open? The reason i ask is because on the Honda RS125 i used to race, they never posessed such things. It was just carb - inlet port - reed petals - squishsparkbang- open exhaust port. Hope that bit makes some sense.
spacemonkey Posted January 22, 2010 Report Posted January 22, 2010 Hey! I've got myself an Aprilia RS250 track bike which i'm in the process of getting ready for a season of trackdays. It was tatty when i got it hence the winter project. I'm also going to beat my mate on his RGV250! Anyway, i'm after some info about the power valves. Now this may seem like a really stupid question, and it probably is! But can i remove or have the power valves on constant open? The reason i ask is because on the Honda RS125 i used to race, they never posessed such things. It was just carb - inlet port - reed petals - squishsparkbang- open exhaust port. Hope that bit makes some sense. You could do that, but why would you? It would make you slower!
speedy sie Posted January 22, 2010 Report Posted January 22, 2010 seen some heavely tuned rgv's and rs's that run with the power valves open,but in my opinion you can get a programable power valve moter,and single one peice power valves,and i reaken this is the best mod,as on a track bike its mostley full chat,and a stage power delivery is not realy needed. sure the kit power valves were one peice,but i could be wrong.(sorry they wernt,they had a selecton of difrent thick ness's to pick from.) and no you carnt remove them as this is just no posible,as this would leave to openings,were the valves seat,and cause you a right head ache. best get the one peice valves,from germaney,and fit them ,sure they are quoite cheep. best tune up is to have the squish band set,as iv seen as much a 1.5mm taken off the head just to get the squich band right.then have the power vales blended into the out let port,this is the best cheep mods.lift the out let port by 1 to 1,5 mm,open then air box up(take out the spliter),blank the carb pipes off,wip out the oil lube pump(run on prmix),fit an engine heat sheild,and all this will make a difrence.
sonic Posted January 22, 2010 Report Posted January 22, 2010 Go to www.rgv250.co.uk and you will find more info than you need. DONT remove them and fit solid ones or it will loose the little midrange it already has.
jimmy Posted January 22, 2010 Author Report Posted January 22, 2010 Thanks for the info! I'll have a gander at rgv250.co.uk. Speedy sie; it was an ex 'Challenge' bike, so the oil pump has been removed and now runs on pre-mix. The airbox has also been de-restricted. I've heard horror stories of the power valves falling to bits and dropping into the top cylinder, hence the question about removal.
Gregorious77 Posted January 22, 2010 Report Posted January 22, 2010 Just keep an eye on the power valves and they should be fine. as sie said find out what the optimum squish should be and set it up properly for best gains. You can change the head gasket for an o ring (requires machining) and put a fatter base gasket in to alter port timing but that may already have been done.
Recommended Posts
Archived
This topic is now archived and is closed to further replies.