My KLX (C1 model) runs 9.5:1 but the C3 runs 10.5:1, just for your info.

Clive W  

Quote:

I'd agree that an oil cooler would be a wise modification, not to mention cheap, and that's my own first step.  You'll notice lots of examples of oil cooled motorcycles than can have significantly increase HP than their air-cooled only counterparts.  

Second, and I'll likely be jumped for this (duck), but as an engine starts to push the performance up, full synthetic oil becomes more and more critical.  There's not a single jet, not a single NASCAR or Indy car that runs on anything other than full synthetic lubricants for internal engine parts, despite what you see on commercials.  So the second low dollar, high payoff thing I'd do is run a quality full synthetic oil.

Third, another low $ way to protect an engine is to limit RPMs.  So I'd say an RPM limiter can pay big dividends.  The more you limit RPMs, the longer the engine will last (to a point.)  I'd stay in the 5500-6500 range as a max RPM.

Now we're getting into more $$$.

I really like Lancer's carbide coat cylinder wall process and I'd have that done no-matter-what if your changing pistons anyway.  That will help alot.

Up the scale would be a longer connecting rod and shorter throw crankshaft.  Does anyone know the current connecting rod length?  At any rate, for high performance engines the connecting rod should be at least 1.75 times as long as the stroke.  In the case of the LS650 a 3.7" (94mm) stroke would necessitate at least a 6.475" (164.5mm) connecting rod.  I'm willing to bet the current one is not that long.  This would decrease peak piston speed and actually allow higher RPMs with the same peak piston speed (the only speed in an engine that really matters.)

Higher RPMs would also demand more airflow.  So cam change, port work, valve work etc. would need to be accomplished to take full advantage of the money you've now spent.

I don't think it's been done, but I'm betting with the above changes you could have a 65 hp Savage.  I don't know how long she'd last, but she'd be fun while she lasted  

That was kinda my plan.  Crankshaft work aint cheap though.  Stroking or destroking is 200-300 bucks, full blueprinting is bout 300 bucks, a custom rod wouldn't be terrible, but prolly 50-100 bucks.  Just blueprinting the crankshaft and shot peening the current rod should give a big increase in strength, 293 plus shipping charges.  This does nothing for transmission strength though, what can be done with a constant mesh?  I think 50hp is a nice number to aim for.  If you get the weight of the bike to 300(not to hard) and keep your weight around 180(significantly harder) 50 horse will put the savage in the mid 12's (estimate) with the right gearing (3.5ish final drive).  That could be acheived with the stock stroke.  695cc's with 10:1 (93 is generally recommended for this cr, of course running 300degrees would probably still detonate, so cooling is a must) with the mods for the necessary flow for this size and compression (porting the entire head, maybe bigger valves, carberator, free flowing air filter/exhaust, more aggressive camshaft...) 50 is not crazy, Lancer already has 42 right?  So lookin for another 20% power over that..  Anyone know the conversion for flow capacity needed for desired power gain?

Oh yea 8000rpm might be the upper limit for a single and beyond the savage, but 7k is not so out there, I think the weight of the bottem end is the current limiting factor for revs...

Go here to play with this yourself, but I calculated a 171% increase in flow over stock to achieve 50 hp at 7500 rpm's.  That seems pretty tough to do, although I haven't played around with this engine...

NOT2FAST: Turbo Calculator