Engine Tuning

[sgrprincees]

Anyone know of ways to make the Vision make more power than it does stock and in good tune?

[greener]

jet the carbs or add nos... duh!

[Rick G]

In years past,  several people bored out the stock liner and raised displacement , close to 600 cc and by changing the liners the reached close to 650 cc. A fellow I spoke to a couple of years ago, had special stroker cranks made, which with the bigbore, raised displacement  to 750 cc and 93 hp. Burke Storti had a Vision with a set of MAC pipes and megacycle cams. of all of this, I think,  a used set of megacycle cams would  the most practicle . (if you can find them)

[bikeseamus]

 No question  Quickest, easiest,cheapest,most accessable,most dramatic improvement would be NOS. It would be interesting to find out how the rods and crank held up to it. Yamaha is notorious for overbuilding their bottom ends. Someone should do this immediately, while the weather is so bad, and let us all know which bikes they beat up on. Fun by the ton! Throw it on a dyno while you're at it and give us the numbers. Good clean fun, if you ask me.

[Silver_Bullet]

Interesting thoughts guys, anybody ever tubocharged one of these things?  Might be a bit tough to engineer, take the turbo off the front pipe, route plumbing to a modified, sealed airbox, or make new intake....hummm, might be a future project.  Seeing first day of 70 degree weather, no rain, but bike still not together, at least a good day to work on it!
Mark

[rick_nowak]

lighter is better! the magazines use test riders who weigh about 140 lbs soaking wet with breakfast and all riding gear. they are also small guys and consequently can tuck in better/more aerodynamic.  thus, faster 0-60 and higher top speeds.  if the average rider on this forum is pushing 170 or more (230 myself) then they have at least a 30lb advantage. that's about a 6% less weight advantage.  substantial.  you cannot keep your vision stock or at least stock looking and take 30 lbs out of it without real work or real money, probably both.  best weight loss is an aftermarket exhaust and maybe once you get it running it right again, more torque where you want it.  aftermarket exhaust-12lbs or so loss.  removal of turnsignals and other useless or questionable appendages, another 10 or so lbs.  now you've done all the easy stuff.  now the real work/$$$ begins.  how about reducing your own personal weight?  now thats at least cheap, just eat less.  sooo easy, note my weight above.  yea, right!

[Humber]

yeah... u are quite right.... two years ago I lost 20kg!!! in 2 months time - I ate practically nothing (1000 kcal per day - notice that a 500 g jogurt is 500 kcal - so 2 jogurts per day...) and went in for jogging as I do today (I feel great).... the difference was noticable..... so to all that consider themselves to be fat - maybe this season u should exchange  V on feet, take some running and next year your V will give u a boner ;D the best tunning possible..... ;D

[Rick G]

Every 10 lbs  the bike weight is reduced is the  equivalent of 1 more horse power. You hit the nail on the head about rider weight, in the 60's , AMA class C riders on Triumphs  or BAS's (500 cc/30.50 cin) were invariably small guys , like Kenny Roberts or Gary Scott. Generaly HD riders were larger  (but not always) even though HD's were flat heads, they were also 45 cin/ 750 cc they succeded in making those antique motors run 150 mph in road race trim.