Handy Don 14,716 #26 Posted Tuesday at 01:04 AM 1 hour ago, Achto said: He did say that the engine was not exactly happy about the whole affair. I've never seen that one either. And yeah, I’d say only the last couple years of short or “mid" frames with a 10 or 12hp would be able to run that 1 Share this post Link to post Share on other sites
WHX?? 52,966 #27 Posted Tuesday at 03:28 AM Yeah look what HP they use to spin a 42 nowadays ... 18 - 20 twins and they used a 10 back in '65. 1 1 Share this post Link to post Share on other sites
kpinnc 15,758 #28 Posted Tuesday at 04:00 AM 30 minutes ago, WHX?? said: Yeah look what HP they use to spin a 42 nowadays ... 18 - 20 twins and they used a 10 back in '65. Leaded gas, cast iron block, and a flywheel that weights more than the whole engine nowadays. Definitely made a difference! 2 Share this post Link to post Share on other sites
Handy Don 14,716 #29 Posted Tuesday at 02:55 PM 10 hours ago, kpinnc said: Leaded gas, cast iron block, and a flywheel that weights more than the whole engine nowadays. Definitely made a difference! (sorta?!) Leaded gas achieved higher octane via the (highly toxic) lead. Unleaded does it using other (less toxic) additives. Energy content is close to the same. That said, the higher the octane the higher the compression ratio can be without engine knock. But do newer engines have lower compression? I don’t know. The heavier flywheel is, I agree, a big factor in smoothing out load variations, but something had to build and sustain the momentum! I think the biggest factor is rate of fuel consumption as part of driving down emissions. I believe that less fuel consumed is not fully offset by increased efficiency so there is a net loss of usable power. That said, IMHO, the single main factor is that consumers are more number conscious than ever (BIGGER is BETTER!). Higher horsepower must be better! My guess is that most of these 18-25 horse units are just not really using the horsepower. 1 Share this post Link to post Share on other sites
kpinnc 15,758 #30 Posted Tuesday at 09:10 PM 6 hours ago, Handy Don said: I believe that less fuel consumed is not fully offset by increased efficiency so there is a net loss of usable power. That said, IMHO, the single main factor is that consumers are more number conscious than ever (BIGGER is BETTER!). Higher horsepower must be better! My guess is that most of these 18-25 horse units are just not really using the horsepower. Agreed. I also think cast iron blocks deliver more power just through rigidity to a point. Again, it's multiple little things adding up to a bigger total. No doubt that newer designs are more efficient. My 23hp Vanguard uses about the same fuel as my K181 8hp at full throttle. Fuel mix ratios definitely can result in smoother running on the old Kohlers, but being too rich or lean on newer engines may keep them from running at all! 2 Share this post Link to post Share on other sites
Achto 29,925 #31 Posted 8 hours ago One thing that I believe the new engines lack is torque. I believe this is because the stroke is shorter on new engines. Longer stroke = more torque. 4 Share this post Link to post Share on other sites
WHX?? 52,966 #32 Posted 4 hours ago (edited) On 11/11/2025 at 8:55 AM, Handy Don said: My guess is that most of these 18-25 horse units are just not really using the horsepower. Got a point there Don. MY Z turn spinning a 48 and two hydros never gets on the gov unless I shove it into tall weeds or use it for brush hogging. Yah it's green & yellow and I abuse it like I stole it. Well ... actually I did it ... stroke is shorter on new engines. Smoother power perhaps Dan? Cheaper to make fer sure. Edited 4 hours ago by WHX?? Share this post Link to post Share on other sites
