fredgold52
New Member
I'm betting some of you four strokers have been messing around with tachometers. I'm curious about what RPM would a person expect to be the Red Line RPM on a stock HS running unloaded?
HS 49cc Red Line RPM??
- Thread starter fredgold52
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Rocksolidperson
New Member
the 50cc 2 stroke revs out at about 8,500rpm and the 66cc is about 7,000 rpm approx, the 4 stroke 50cc i believe are 7,500rpm
fredgold52
New Member
Thank you Rocksolidperson (good name!) that's very helpful.
The_Aleman
Active Member
Redline's about 8000, although they can take more than that for short bursts. The GXH50 can take it for a little longer than the HS can, due to tighter engine construction and a better connecting rod. Extended high RPM can cause the oil slinger to break off either engine, and even more extended may cause the connecting rod to break.
andrewflores17
New Member
my first hs broke buy over reving unloaded just becarefull with the little beasts
The_Aleman
Active Member
Yeah, it's pointless to rev em up that high unloaded, IMO.
The power falls off over 7500 too, so revving much over that is like whipping a horse when it's already at top speed lol
The power falls off over 7500 too, so revving much over that is like whipping a horse when it's already at top speed lol
This is exactly correct. They can only take it for short periods due to the lack of lubrication to the big end con rod. The con rod welds itself to the rod journal, often breaking or bending the con-rod in the process. You can modify the rod for a bit more oil flow, but this has to be done carefully. After that, I'm guessing the limiting factor would be the con-rod itself, oil slinger, or valve springs.
fredgold52
New Member
The reason I asked for unloaded red line rpm is because from that I can figure roughly what it should be under load, and from that about what mine should be running hauling my big butt around. Best I can tell, mine runs at about 5K under load. And that's just fine. It's also not where I run it very much.
I run the bike up to a comfortable speed, then back off the throttle and let it freewheel. RPM drops to idle during freewheeling times. At this rate, my HS 49cc will last 3,000 years I'm guessing. Well, maybe not.
I run the bike up to a comfortable speed, then back off the throttle and let it freewheel. RPM drops to idle during freewheeling times. At this rate, my HS 49cc will last 3,000 years I'm guessing. Well, maybe not.
The_Aleman
Active Member
Be careful not to lug it tho. The Huasheng doesn't have much torque at all below 4000RPM. It's made to run 5-7K all day and it will.
flmotorbikes
New Member
Same my power loss it around 5000 rpm
The_Aleman
Active Member
What you talking bout willis? If your power falls of then, you prolly got either a valve adjustment problem or something else going on...