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Post by learae on Dec 9, 2012 13:09:24 GMT -6
Oh perfect, thanks  |
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Post by learae on Dec 9, 2012 13:09:02 GMT -6
I figured out where the washer was from, the fuel ratio needle.
Does that go back in needle, spring, washer, o-ring, into carb?
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Post by learae on Dec 9, 2012 1:10:32 GMT -6
The valves are making a pretty loud ticky ticky, but I'm not sure how loud a clatter would be considered. I can hear the valves over the engine when stepping away, so I think that's too loud and I'm going to try tightening them up to .003" to see where it's at then.
The scooter usually starts right away if I roll the throttle back as I push the starter button.
The fuel ratio screw doesn't seem to have much of an effect on the idle speed. Not as much as it should, I think. I had more of an effect after I adjusted the valves.
I pulled the carb and started cleaning it out, and a small flat washer fell out while I was spraying down the carb body. It's really small. Any idea where it came from? All of the external screws have their lock washers, but the missing washer is too small to fit on any of those, anyways.
Thanks again!
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Post by learae on Dec 6, 2012 11:54:42 GMT -6
Alright, before I adjusted the valves I tried to ride the scooter to work. I got about 4 miles down the road when I lost all power, couldn't even move, and the engine died if revved beyond 3000 RPM. So I pulled over and, after a bit of walking and a no-fun day, set the valves.
The exhaust valve was tight! After resetting both valves to .004, the engine runs good and I got my power back. I did have to adjust the carb some more as well, and I think I am going to tinker with it a little bit still. I also replaced the spark plug while I was at it.
I can hear the valves clicking now inside. Does that mean the spacing is too big? It's at .004 and I reconciled that against the .005 which does not fit.
In order to warm the engine up, I still need to give it a lot of throttle for the first 5 minutes. Once the engine is warmer, I can let off the throttle and it idles poorly around 1000 RPM until finally coming up to idle at about 1500 now. If I let off the throttle while the engine is cold, it dies almost immediately.
When idling and warm, the RPM still hiccups sometimes. You said this was caused by the mixture being too lean, but it seems to get worse when I richen the mixture. Could this be caused by something else?
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Post by learae on Dec 4, 2012 15:51:30 GMT -6
I adjusted the ratio 3/8 of a turn richer and dropped the idle screw to idle at about 1900 RPM. If I go any lower, it's not a very smooth idle. It seems to be running good and the idle is steady when sitting and warm. After the adjustment I got some more power and speed back, so much better! I think I will go another 1/8 turn richer before I go home tonight and see where it puts me.
I gave it a quick twist of throttle while it was warming up this morning and the RPM came down so low that the engine almost died. Once it warmed up, the engine didn't try to die anymore, but I am unsure how quickly it should be coming down. It seemed to come down at about the rate the tire slowed, which makes sense. I think.
The rear wheel doesn't start spinning until around 2800-3000 RPM. Should it be sooner?
It's still having trouble starting cold. I need to give it constant throttle to keep the RPMs high enough so it doesn't stall out. It seems especially bad when it's only cooled down some - like at the gas station where the engine is off for just a couple minutes. It starts better when it's completely cold, say after a night of sitting.
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Post by learae on Dec 3, 2012 20:16:44 GMT -6
Alright I swapped that enricher casing(?) for one I had in another scooter
I got the engine tuned, I had to go about 2.5 turns in with the ratio screw. It's idling at around 2500 RPM now, but sometimes it bogs down for a few seconds to 2000 RPM before going back up. Any idea what could be causing that problem?
I went for a test ride, and got it up to 50 MPH after a 1/2 mile straight away at WOT. It's still not doing as well as it was just a few days ago. I used to be able to get up to 50 pretty snappy, and still had 1/4 throttle left if I needed it.
So, what should I check out next?
Thank you!
Lea
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Post by learae on Dec 3, 2012 11:58:33 GMT -6
Thanks for the quick replies
I took the enricher off and found the engine wouldn't even run. I held the enricher in place and got it started and warmed up. it idled slow until it warmed up, but then idled at 3200 RPM. Wow! I slid the enricher off and the engine died, but it was extended properly. While putting it back in, i discovered that the top hole holding the enricher in is stripped out big time. I took the carb out and I'll get a mechanic to put a helicoil in that hole and get a shorter screw... The screw was bottoming out against the carb so the last person to work on it probably messed it up.
I am guessing that repairing that will fix part of my problem; I will then adjust the mixture and hopefully get my power back :-)
So, while i have the carb out, should i open it up for a cleaning? Or would i be better off leaving well-enough alone?
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Post by learae on Dec 3, 2012 0:18:05 GMT -6
Hi All! First post!
I recently bought a 150cc Shanghai Shenke and it has been running great until yesterday.
It is cold outside now, and I have to work on it outside, so I wanted to get your opinion before I freeze to death taking things apart.
The scooter usually starts right up, but it has a rough idle around 1000 RPM until it warms up, when suddenly the RPM jumps to 1800 and sounds so much smoother. As I understand, when cold, the enricher should cause it to idle higher before dropping down to speed when it's warm. I haven't taken the enricher out yet to test.
Anyways, yesterday I went for a ride into the city which is about 10 miles. During this time, the scooter was being VERY well behaved, and I felt like I had more power than usual. I wish I had a better description, but I wasn't paying too much attention at this time.
When I started to come home, I let it warm up as usual and it still idles at the same place, about 1800 RPM. I noticed, however, that I was not getting much power. At WOT I was getting only 5500 RPM and couldn't get above 40 MPH even in long straight areas.
It felt like the throttle behaved mostly normally until I hit that 5500 RPM range, and then giving it more throttle did nothing to the engine. But, I did lose power along the entire throttle range.
So I got home and put it up on the stand, and pulled the throttle wide open. The engine revved as normal, hesitated at that same 5500 RPM area for a moment, and then jumped up quickly to 8000+ RPM. I then let it stop and pulled the throttle again, and it quickly throttled up all the way without any more hesitation at 5500 RPM.
Thinking that was strange, I went for another ride and still could not get above 40 MPH and 5500 RPM at WOT.
Since the kick starter doesn't engage, I was thinking I'd take the CVT cover off first and try to fix that while checking on the clutch, belt, and variator.
What should be my next move? Do any of these symptoms suggest a particular fix?
I am pretty handy, but I've never adjusted a carburetor before. I think that might be the next step...
Thank you,
Lea
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