Less torque after engine is run for a few miles

GoldenMotor.com
May 9, 2013
90
0
6
Laguna Beach, Ca.
I live on the top of a steep hill (about 30+ degree) grade that is about 100 or so feet long. If I take a short ( a mile or 2) cruise and come back home it pulls fine with barely any pedaling effort at the tippy top, but if I am on the road for more than 15 minutes and come back up the hill I have to put some effort into getting to the top and the engine is barely cranking at less revs than the normal idle speed at the end. I am running a Dax 69cc F80 with an RT (Puch clone) head and everything on the engine is tight with no leaks. It runs great on the flats and slight hills all day long. Does anyone have any suggestions as to how I can regain the same low end "grunt" that I have when the engine is relatively cool? It's always been this way and I'm kinda stumped.
Thanks
 

Davezilla

New Member
Mar 15, 2014
2,705
10
0
San Antonio Texas
Is the engine broken in yet? It sounds to me like the engine may be getting hot by the time you return and just don't have the same power it did while warming up...
If the engine is fairly new and less than 3 tanks have gone thru the engine that's most likely the problem and it'll get better as it breaks in.
 
May 9, 2013
90
0
6
Laguna Beach, Ca.
Yeah, that makes sense, Dave. I've burned through almost 2 gallons since installing a fresh jug, piston and rings. Maybe running a cooler plug will help? I'm using an NGK b6hs right now, I'll try a b7 and see if that improves matters (we're having a heat wave in So Cal right now)
 

crassius

Well-Known Member
Sep 30, 2012
4,032
158
63
USA
unless there's a serious problem, I never attempt a tune before 300 miles are on it