Engine Trouble Major lose of power

augustwinds

New Member
Joined
Jun 5, 2020
Messages
16
ive put roughly 100-120 miles on my zeda 80 mounted on a big 700c road bike ( 54 tooth sprocket). recently ive been having MAJOR lose of power on hills that it used to bring me up no problem (roughly 15-20 up the hills no problem with no assist needed by pedaling) now it wont even make it half way up most of the hills even with assisting pedaling.

issues started when i had a souder give on on my magneto ( was giving off and on issues right b the souder gave out) i replaced it and i got spark back but now has ALOT less power. 1 other detail is it will only run "right" in the top most clip spot on the needle (used to be set to 3rd down) other wise acts like its drowning itself in gas of RIDICULOUS 4 stroking at all but barely any throttle.

what ive tried is 1 clean carb

2 opened head and replaced head-gasket and re-seated rings to be safe (seems to be getting ALOT hotter REALLY fast too)

3 tried all clip positions on needle

4 checked if exhaust was clogged or anything

5 changed to fresh premixed gas (ranging form 16:1 - 40:1

kinda at a loss here (new to motorized bikes but ive done some small engine work)

ANY input is help kinda dont wanna turn it into a extra large paper weight if i can help it ...

live in WV if there is any locals who are willing to help (given the covid stuff going around understand anybody being hesitant)
 


HumanPerson

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Joined
Oct 12, 2019
Messages
1,843
I live in VA and have a motor, been port matched from case to cylinder, sleeved.
With malossi gudgeon pin and bearings. 1 1/8ID exhaust system with KX65expansion chamber.
Carb is RunTong carb. Set for our elevations. Alot of other sh*t, read my posts since we're next door neighbors.
 

HumanPerson

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Joined
Oct 12, 2019
Messages
1,843
All of my gasbike stuff is for sale, and I have alot of stuff.

You need to pull those hills neighbor, damn..I was in WV two days ago down by monterey.
 

HumanPerson

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Joined
Oct 12, 2019
Messages
1,843
Our weird elevations make things weird for our engines.

Your bottle neck is at the exhaust port from cylinder out to the header tube.
You have stock? Not good. I don't run stock nt carb.
 

augustwinds

New Member
Joined
Jun 5, 2020
Messages
16
my question is this tho how is it the exhaust port hiding it back if it was running perfectly (able to take me 20 + mph up hills) b4 and then after the magnetos starts going boom now its exhaust port (not trying to put down ur sugestion justtrying to follow the logic)

and yes stock nt carb
 

Chainlube

Well-Known Member
Joined
Jan 5, 2020
Messages
1,387
ive put roughly 100-120 miles on my zeda 80 mounted on a big 700c road bike ( 54 tooth sprocket). recently ive been having MAJOR lose of power on hills that it used to bring me up no problem (roughly 15-20 up the hills no problem with no assist needed by pedaling) now it wont even make it half way up most of the hills even with assisting pedaling.

issues started when i had a souder give on on my magneto ( was giving off and on issues right b the souder gave out) i replaced it and i got spark back but now has ALOT less power. 1 other detail is it will only run "right" in the top most clip spot on the needle (used to be set to 3rd down) other wise acts like its drowning itself in gas of RIDICULOUS 4 stroking at all but barely any throttle.

what ive tried is 1 clean carb

2 opened head and replaced head-gasket and re-seated rings to be safe (seems to be getting ALOT hotter REALLY fast too)

3 tried all clip positions on needle

4 checked if exhaust was clogged or anything

5 changed to fresh premixed gas (ranging form 16:1 - 40:1

kinda at a loss here (new to motorized bikes but ive done some small engine work)

ANY input is help kinda dont wanna turn it into a extra large paper weight if i can help it ...

live in WV if there is any locals who are willing to help (given the covid stuff going around understand anybody being hesitant)
Wipe the bottom of your motor with a paper towel and see if it's oily.
 

Street Ryderz

Well-Known Member
Joined
Oct 14, 2016
Messages
3,560
From the break in did you re jet the carb? Over heating or getting hot quickly when rich is usually blow by witch would make sense since you can't re seat the rings,and would explain the loss of power.You can usually see discoloration of the piston below the ring's when this occur's.
 
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