I have a ds650 2001 with these mods, K&N air&carb jetted to 195,full race big gun,Ron Woods CDI box, put the cdi box on about a month ago. I've been riding several times and sunday I was out riding for about an hour when I noticed pattering in mid r's that progressively got worse!! When you were in nuetral an rev it up it sounded fine untill you put in gear. I think it is the valve springs, floating a valve maybe? If this is the case can I change the springs to titanium and change the cam to a higher lift like 425 with out doing head work or a piston. Or should I go to a 395 sport cam,I should'nt need to do the head or piston then right?

 

nobody knows nothin come please.

 

Wish I could help. Still a newbee.[img]i/expressions/face-icon-small-smile.gif[/img]

 

hard to troubleshoot wierd sounds over the net, its hard telling exactly what it could be.
but if you suspect something in the valve area, first check valve clearance. with piston at top dead center of compression stroke all 4 lobes will be facing out away from each other. use feeler gauge to measure between lobes and tappets (buckets) - all clearances should be over .004" - .006". if one is tight, with no clearance, then that valve is not closing all the way, making adjustment imperative. its easy to check the clearance - more info is available around here on how to adjust if they end up needing it - do a search on valve adjust and you will find a hyperlink to a site that has detailed instrucitons and pictures.

 

I can't be much help, but I was snooping around on the BMW F650 page and seems there might be some information there. Here's the link if you are interested.


BMW Page