Mc2Stroke
Member
Hi this is my second thread here, I originally posted some questions about my new 49mm iron sleeve which I took apart as I knew there had been others with scratched sleeves etc (mine was pretty scratched in two spots) I got a little busy and didn’t update(maybe I can throw some picture up and update there or here eventually) for the scratches I honed the cylinder sleeve then slightly chamfered the port openings and cleaned them up/ got rid of burrs / made them even afterwards got it all put back together and finally on the bike.
Here comes the new issue, after finally getting it on the bike and set up so the chain wouldn’t pop off while riding (or so I thought) I tried for about 30-45 minutes straight to get it started. At first I would just pop the clutch (fuel on and choked) and I got some pops and bangs out the pipe with a little smoke but it would not run. I started going faster and pedaling through the compression which is a little harder than I thought being it a pretty small engine ( I tried opening the choke to different positions)
Finally it started with the choke about half way open but I had to keep giving it throttle or it would die, I rode it about a 3/4 of a block back to my garage and wham back tire locked and I could tell by the sound the chain threw and it turned out it tore a spoke right through the rim.
Stupidly and in my excitement to get this thing going I must not have tightened the chain guide/tensioner tight enough cus it moved just enough for this to happen. Determined to at least get the engine running smoothly I tucked the broken spoke back and got the bike started again ( just rolling it down the driveway a couple times was working to start it at this point), it would start then die until it started for about 30seconds at which time I was blipping the throttle to keep it running then it died.
Now feeling pretty warm it would not start again.
I kind of let it sit for a while because I was busy but finally got the rim fixed and trued as best as possible, I’ve got the chain and guide/tensioner fully tightened. I put a smaller jet in it( stock was in between 70 and 75) I put in a 65 because when it did run it sounded like it was sputtering not the more hollow sound of a lean bog.
It now fires up within the first few tries but only if I have the choke about half way and if I give it throttle and it runs very rough. Then if I sit there and rev it lightly as it warms up it eventually dies and is almost harder to start ( sometimes won’t start back up at all when warm) I have moved the needle both directions with little very little difference. I’ve checked the plug which still looks new cuz it hasn’t run really long enough to show anything, I also checked the cdi (6.24 ohm) the magneto (.318-.320 ohm) the kill switch is not stuck, it’s getting fuel/ the carb is sealed with an o-ring, head bolts are tightened correctly/ gaskets looked good when I had it apart, piston rings were good( brand new) cylinder honed freshly…
There is no Ethanol free gas where I am so it’s 91 octane with 7-10%ethanol or so mixed with Powercare Synthetic Blend at 30:1 for break in. (Manual said 16:1 break in 20:1after but I though that was a little crazy based off past experiences with 2strokes)
Ive never had a 2stroke do this cuz it needed a different jet but was going to try my smallest jet to see if that makes a difference if not the biggest. The only jets I could find was a kit ( #50-80 in increments of 5) it’s the new bofeng NT knocknoff.
The bike is all stock accept a mz65 clone.
I have not been able to spray car cleaner to test for leaks cuz it won’t run long enough or well enough to do so, but when I had the head and covers off everything looked to be in place. (Was thinking of checking to see if magneto has a good ground and if the magnet is on correctly.
Any help would be appreciated, thank you.
Here comes the new issue, after finally getting it on the bike and set up so the chain wouldn’t pop off while riding (or so I thought) I tried for about 30-45 minutes straight to get it started. At first I would just pop the clutch (fuel on and choked) and I got some pops and bangs out the pipe with a little smoke but it would not run. I started going faster and pedaling through the compression which is a little harder than I thought being it a pretty small engine ( I tried opening the choke to different positions)
Finally it started with the choke about half way open but I had to keep giving it throttle or it would die, I rode it about a 3/4 of a block back to my garage and wham back tire locked and I could tell by the sound the chain threw and it turned out it tore a spoke right through the rim.
Stupidly and in my excitement to get this thing going I must not have tightened the chain guide/tensioner tight enough cus it moved just enough for this to happen. Determined to at least get the engine running smoothly I tucked the broken spoke back and got the bike started again ( just rolling it down the driveway a couple times was working to start it at this point), it would start then die until it started for about 30seconds at which time I was blipping the throttle to keep it running then it died.
Now feeling pretty warm it would not start again.
I kind of let it sit for a while because I was busy but finally got the rim fixed and trued as best as possible, I’ve got the chain and guide/tensioner fully tightened. I put a smaller jet in it( stock was in between 70 and 75) I put in a 65 because when it did run it sounded like it was sputtering not the more hollow sound of a lean bog.
It now fires up within the first few tries but only if I have the choke about half way and if I give it throttle and it runs very rough. Then if I sit there and rev it lightly as it warms up it eventually dies and is almost harder to start ( sometimes won’t start back up at all when warm) I have moved the needle both directions with little very little difference. I’ve checked the plug which still looks new cuz it hasn’t run really long enough to show anything, I also checked the cdi (6.24 ohm) the magneto (.318-.320 ohm) the kill switch is not stuck, it’s getting fuel/ the carb is sealed with an o-ring, head bolts are tightened correctly/ gaskets looked good when I had it apart, piston rings were good( brand new) cylinder honed freshly…
There is no Ethanol free gas where I am so it’s 91 octane with 7-10%ethanol or so mixed with Powercare Synthetic Blend at 30:1 for break in. (Manual said 16:1 break in 20:1after but I though that was a little crazy based off past experiences with 2strokes)
Ive never had a 2stroke do this cuz it needed a different jet but was going to try my smallest jet to see if that makes a difference if not the biggest. The only jets I could find was a kit ( #50-80 in increments of 5) it’s the new bofeng NT knocknoff.
The bike is all stock accept a mz65 clone.
I have not been able to spray car cleaner to test for leaks cuz it won’t run long enough or well enough to do so, but when I had the head and covers off everything looked to be in place. (Was thinking of checking to see if magneto has a good ground and if the magnet is on correctly.
Any help would be appreciated, thank you.
