74jaj 0 Posted October 2 So I have a honda rubicon 500 with power steering, have not had it long but I was able to get up to at least 55mph with no problems without reaching the limiter. But all of a sudden now it seems to be running much higher rpms then it used to around 40mph and now it can barley go 52 and really struggles to gain speed around the 45 and above range. any ideas on what might be happening? Share this post Link to post Share on other sites
jeepwm69 7,420 Posted October 2 Welcome aboard. How long has it been since the oil was changed? The Hondamatics run on oil pressure, so you need the proper amount of JASO MA rated oil in the engine, and I'd run full synthetic (I use Rotella T6) and keep it fresh. Could also be a bit of trash in the carb, or a dirty air filter. Share this post Link to post Share on other sites
74jaj 0 Posted October 2 (edited) I just changed the oil and put in a new oil filter. The air filter is clean. It didn’t really help at all. Is there a chance it could be the oil pump? Edited October 2 by 74jaj Share this post Link to post Share on other sites
jeepwm69 7,420 Posted October 2 4 minutes ago, 74jaj said: I just changed the oil and put in a new oil filter. The air filter is clean. It didn’t really help at all. Is there a chance it could be the oil pump? I had a long talk with @Brian Bertram about these, and he said that oil pump failures are pretty much non-existent after Honda redesigned them in 04. If it's not starving for air, and the carb doesn't have an issue, I dunno. I will say it's foolish to ride one of these utility ATV's that fast. Not saying I didn't do it when I was younger and dumb, but these utility wheelers aren't designed to be ridden at those speeds. Share this post Link to post Share on other sites
74jaj 0 Posted October 2 I don't usually ride it that fast I was just wondering mainly since it seemed to be running higher rpm’s at around 40mph. Share this post Link to post Share on other sites
jeepwm69 7,420 Posted October 3 18 hours ago, 74jaj said: I don't usually ride it that fast I was just wondering mainly since it seemed to be running higher rpm’s at around 40mph. Maybe @toodeep might have an idea. You haven't changed anything else (tires for example) on the machine? Share this post Link to post Share on other sites