86 vmax with 150 hp stock?

dnthmn87 · Sep 4, 2011

I've had my 86 vmax for a few years and was told when I bought it that it had 150 hp just like the 85s. I didn't know anything then, the bike turned me on plenty so I bought it. When I looked into it later, all I could find was that the 1985s only had the 150 hp motor. I finally found someone else nearby that owns a few max's, and seems to know alot about them. He looked at the production date on my bike which says 12/85, and about crapped his pants telling me that my bike has the Japanese spec 150 hp motor... Anyone else know if this is true? And if this means my bike is worth more than if it were made in late 86 or something? Any way to tell for sure, i've never ridden another one so I dunno if its faster or what, she needs a good tune up anyways.

naughtyG · Sep 4, 2011

ALL Max's from 1985 to 2007 have the exact same motor, developing 147BHP AT THE CRANK.

That translate into around 120 BHP at the rear wheel, due to transmission losses (shaft are WAY less efficient than chains..)

Only the Japanese and French markets have received emaciated versions of the Max limited to 100 BHP (at the crank) and easily identified by the fact they lack the Vboost.

So there ya go, it's 147 HP at the crank, all years up to 2007. Only difference in very early '85s was the exhaust, but that accounted for very little.

If you want a few more ponies (and less weight), dump the OEM exhaust system and get a full aftermarket one and a jet kit from Sean Morley - that makes it quite a bit pokier than stock.

dnthmn87 · Sep 4, 2011

Thanks for clearing that up. This guy claims that the motors in 1985 had a few slight geometric dimensions and differences blah blah blah so they were faster. I have the individual K&Ns to replace the stock air box, not installed yet, and would like to get my hands on a FULL aftermarket exhaust, and a jet kit and put all three on at once. And it sounds like i'd need a crankcase breather or somethin?

naughtyG · Sep 4, 2011

dnthmn87 said:
Thanks for clearing that up. This guy claims that the motors in 1985 had a few slight geometric dimensions and differences blah blah blah so they were faster. I have the individual K&Ns to replace the stock air box, not installed yet, and would like to get my hands on a FULL aftermarket exhaust, and a jet kit and put all three on at once. And it sounds like i'd need a crankcase breather or somethin?

You'll need a crankcase breather if you use pod air filters, yes, as the OEM airbox connects to the crankcase.

BUT - don't bother fitting these until you get a full exhaust system - they will do nothing but make your bike run like ****! Simple: way more air in + no where to breathe it out through the OEM exhaust = poor performance.