So you built a snowbike and were instantly hooked. You asked yourself why you hadn’t found this sport sooner. It didn’t take long before you’d mastered riding and we’re looking for more power. So where to go from here?
A turbo snowbike has your interest. Is it the “be all end all” of engine upgrades? Well, yes and no.
Turbocharging an engine has some definite advantages. The power we lose by riding at high elevation can be recovered and then some with boost. EFI bikes are candidates to accept a turbo because we can add fuel controllers to deal with the additional fuel requirements. Power output claims are all over the place. Up to 100 additional HP one company claims. I’m more than skeptical on that one, but I think 25-50 hp is reasonably attainable if fuel octane and compression ratios are paid attention to.
So that’s great, it is possible to almost double our engine output with a turbo if we do everything right. So what’s the downside? Well, you won’t likely be running a fancy third shock in place of a strut rod as most turbos (not all) will interfere with mounting and plumbing intercoolers and such. And there’s the cost. It’ll probably set you back about $5-6k in Canadian dollars.
Turbos work best with spooled up motors that like to rev, so if your current ride is some big bore long stroke, slow revver, it may not be the best option. It seems that a 450 MX bike, or even a punched out 450 MX bike suits the turbo best. Yes, many have enjoyed some success with 500cc and larger displacement bikes, but their lower operating RPM’s can limit the full potential of having extra boost.
Lastly, I have to point out that when riding a boosted bike, when you get on the loud handle, you’ll likely hit the rev limiter pretty quickly with all that extra jam. Then you’ll need to shift into the next taller gear. During the shift, boost can be lost, so now you’ll have to fandangle the clutch get the turbo on step (building boost) again. It’s a bit of a dance, but some practice in keeping the turbo spooled up, without clanging off the limiter and you find the happy RPM where everything works.
Where Turbos Work Best
If you’re riding terrain with wide open slopes, the turbo will reign king. In the super tight treed draws with creek beds where you’re only massaging the throttle with short bursts, it may be less of an advantage.
And for the all-out weight conscious, it could add approx. 20 lbs. to the bike.
Dollar per HP gained? It’s hard to tell without knowing how much power these bikes are putting out. I’ll let you run the math based on the numbers you believe.
~ Ian McKill, Riders Edge Suspension, Vernon, B.C.