Engine Trouble Another power loss story

[danlandberg]

Well THANK YOU for the concern REALLY! I've missed two days of work ....so far, But i've been through this many times before. I'm 49 and don't know it, but I am learning that it is taking longer to shake a scrape off!!!

 

[jeffuehrer]

I have recently experienced a loss in power, also. I just reached 2,000 miles on my 66cc with all the original parts minus a few bolts. I checked the muffler (I was getting some drips so I sealed it with some copper gasket sealant), replaced the in-line fuel filter (I was getting particles blocking the jet a couple of times), changed the spark plug (I didn't need to though it was a nice tan color). I purchased a new piston and rings and will try that next. I have a brand new spare motor waiting in case this one is toast. She has served me well. 20 ft/second = 13.636364 mph.

"If it ain't broke, fix it 'til it is."

 

[Fabian]

I am completely lost as to the point of the lady being in the photo. It's a bit like scantily clad women holding boxes of bananas at a primary produce trade show,,,,,,, to sell,,,,,, bananas.
It's completely ridiculous.

To associate scantily clad women with our hobby/transport is also ridiculous.

 

[BchCruizer]

After over 1200 miles of happy commuting, my happy time started not being so happy My friend 5-7 Heaven and I are planning on some fun Island rides, and I am trying to get the old girl together. I was sorta thread jacking the carb thread, so started here.


Details are:
- 66cc Gasbike kit, just a basic motor on a cheap beach cruser
- 36T sprocket, 12 gauge spokes and upgraded rims
- NGK plug, upgraded wire, and sickbike parts bolt kit
- Rubber fuel line with inline filter

The bike was running great, rolling at 25-28 easy, had hit 35 on flats with no wind. I rode it over 100 miles a week, and was a daily rider for months. I was just bragging to a friend how great the bike was running. Then I rode it home, and noticed no power, serious bog when I hit the throttle, and it was surging RPM at idle.

- Started to investigate, my main guess was a carb problem.
- I redid the gasket on the intake port, and 5-7 had a sparke pocketbike carb setup. After that the bike ran better, no surging, but would not rev up on the RPM's.
- Checked the fuel flow, and it was a trickle. Pulled out the in tank filter of the petcock, it is better, but still not a gush.
- Really no change in performance.
- Thinking the exhaust might be clogged, I put a spare I have on the bike, also no change.
- Swapped the plug with the unused stocker, and it is about the same still.
- Pulled the head, and I was suprised to find no gasket. No signs of blow out though. It was greasy and wet, I cleaned it up. Cmpression seems strong with the thumb test, I can get a gauge to check if needed.
- There is some leakage at the base gasket. I will prob try taking it off and just doing the high-temp RTV.
- I ordered a new head gasket and slant head, will see if that helps.

I will keep everyone posted. Not sure what else to try yet. If I have to buy a new engine I will. I my gasbike

Ed

Bummer! I got 5,000miles outta my last kit and I only had to change a couple drive wheels and adjust the carb a few times. I never had good luck with those chain drives. I switched to friction and its proven to be the better choice for my needs!

 

[Ludwig II]

I am completely lost as to the point of the lady being in the photo. It's a bit like scantily clad women holding boxes of bananas at a primary produce trade show,,,,,,, to sell,,,,,, bananas.
It's completely ridiculous.

To associate scantily clad women with our hobby/transport is also ridiculous.

Listen mate, if riding one of these gets me the "company" of scantily clad young ladies, I'm going full steam ahead.

 

[Fabian]

It would be a wonderful pipe dream but unfortunately anecdotal evidence suggests that motorized bicycles don't attract scantily clad young ladies; ironically, those women are attracted to other forms of transport with an engine, especially if wearing a Ferrari badge and a senior male driver with a Gold American Express credit card for her personal disposal.

 

[Ludwig II]

I'm 59 and I have a Mercedes baseball cap, is that any good?

 

[Fabian]

Ludwig, you might find it a hard score because women are getting picky these days; they feel a sense of self entitlement to getting a man with both model good looks and serious money, but you might just find one who has lowered her standards; deluding herself that your Mercedes baseball might be a direct link to a well stocked bank account that's a mobile cash dispensary for her personal use.

 

[jeffuehrer]

Is this motor toast?

I have recently experienced a loss in power, also. I just reached 2,000 miles on my 66cc with all the original parts minus a few bolts. I checked the muffler (I was getting some drips so I sealed it with some copper gasket sealant), replaced the in-line fuel filter (I was getting particles blocking the jet a couple of times), changed the spark plug (I didn't need to though it was a nice tan color). I purchased a new piston and rings and will try that next. I have a brand new spare motor waiting in case this one is toast. She has served me well. 20 ft/second = 13.636364 mph.

Well, after inspecting everything I discovered that the ?arm bearing assembly? (arm.jpg and arm2.jpg) was damaged and there was A LOT of side-to-side play on the piston. I don't know if that was the cause for the power loss but I decided to throw my new motor on regardless. I was hoping I could get some feedback from some of the senior members on here for some insight. Your input would be greatly appreciated. Thank you.

 

[Fabian]

Wow, the engine would have been making a horrible rattling sound, well before the brass bushing was completely hammered out.

One of my engines had a similar small end connecting rod bushing; and when the rattles got so noisy that i could take it anymore, the top end was disassembled for inspection.

The bushing had a total of 0.7mm ovalisation which is way, way, way less than the bushing in the photos.

For the life of me, i can't even begin to imagine how you could have not only ridden the bike with such a badly damaged small end bushing (before it reached the point of total failure), but put up with the insane rattling noise; giving permanent hearing loss for anything more than 30 seconds.