how much horsepower does a Yamaha G1 have?

[bac512]

I just recently got a project cart, with a G1 motor all taken apart, missing a few pieces.... I'm trying to figure out how much horse power that motor has... Is it going to be enough to carry 4 adults at up to 10 mph? If not, how much horsepower should I be looking for?

[rib33024]

I,am thinking it is 11hp, but I've been wrong before, --OH did I say that out loud-

[Gregster]

I thought I read somewhere on this site that it is about 8 hp

[GMB74]

The Yamaha manual does not give specs for horsepower, but I have heard 8hp mentioned on this forum. I do not know where this spec came from or if it is accurate. Some members here were Yamaha techs back in the day when these were current models, maybe they can shed some light on this factoid. I can tell you this from the manual: stock G1's were governed to a top speed of 12 mph. Max. load is 748 lbs, seating capacity is 2 persons. If you put a rear seat on to increase the seating capacity to four, and some of your passengers are, um, stout of stature, your buggy may huff and puff some to get up hills. There are drivetrain mods you can do to help you attain your goal, however. Shimming the secondary clutch for more torque and installing a Plowman's performance belt would be a good first step.

[sho305]

They are faster than the 9hp 4 stroke yamahas, they also get more rpm for higher top speed stock. You don't have a reverse in the trans in those, so be careful putting in an engine that does not run backwards like that one. You can adapt a bravo sled engine with that ignition to work, but if it runs good it can pull four people around. You will have to work on the body, they can flip up with weight on the rear and you need supports under it.