ok im thinking about ways to make some power out of the vfr. has anyone tried to get a cam grind done on the stock cams? maybe something like rc30/rc36 spec? is the vfr cam able to do handle such a modification without problems?
just looking for power options on my 3rd gen.
oh, what about ignition advancing? anyone tried that?
I would assume that you have to build up the cam profiles, THEN grind them down to RC30(?) specification for RC30 style induction. You usually need more cam lift and duration for more power.
im sure if you could specify the center you want and your lift and duration, a cam builder could likely weld up and grind the spec you want. wouldnt be cheap im sure for such a one off project. as far as ignition advance goes.... with the stock cam, carbs and such, i dont think ignition advance would give you much benefit
Keep in mind that there are always compromises in this. What's your budget? How much down time are you willing to sacrifice? Do you want it to stay a street bike, or do you plan on it spending most of it's time on the track? ...and so on. (Sorry, I'm reading Kevin Cameron's "Sportbike Performance Handbook" again, and he really makes you think about this stuff. I highly recommend it!
IMO, cams are pretty extreme for a street bike, and you will likely lose some rideability in the deal. You stand a good chance of changing the great, flat torque curve of the V4. If you are going to open up the engine, a big bore kit would give you the most results, and you would make gains everywhere. By then, you're talking probably $3500, though.
The chapest thing that will give you more "boost" is gearing. Synchronizing and tuning the carbs are "free" HP you gain back, as the carbs may have slipped out of tune, and you don't tend to notice gradual things. Bolt on's like a pipe + air filter + jet kit would help a little.
Contact Dave Dodge at DRP Performance (drp123 at mindspring dot com). He offers a Stage I, II, & III kits for the 1000R. I haven't checked with him for any other generations.
Contact Dave Dodge at DRP Performance (drp123 at mindspring dot com). He offers a Stage I, II, & III kits for the 1000R. I haven't checked with him for any other generations.
Pretty sure Dave only deals w/ VF motors, not VFR's...
my induction will be via Gixxer 600 throttle bodies with the secondary throttle blade removed and megasquirt to control the injection. i have yet to decide what i want with exhaust, i was leaning towards the tok tokkie setup, but if i can find a gen 4 set of pipes i may just go that route. OR make my own pipes and run a can on each side of the bike like on a TL1000R.
this bike will be a street bike. if cams are excessive, then i guess ill just focus on the bolt on parts. i really dont want to open up my engine if i dont have to. but it DOES have 33,000 on it, and the cams have to come out for a valve adjustment anyway.
anyway, i was thinking igniion advance could be had with an offset keyway or something, but i really dont see how that could be done looking at the factory service manual.
i just want to be able to keep up with the 600's around here. i have ye to ride this bike so i dont know what kind of power it has, but my 750 katana gets left behind.
im just looking for ways to improve power down the road, as well as right now.
Just curious, how much squish space is left at the VFR heads for any compression upgrades (domed pistons?). Stroking the engine might not be possible because of gear driven valves.