I broke down....[ NOW FIXED] - now with pics

[Lumor_uk]

My bike broke down help

Was just popping to the shops and it died then wouldn't start again. I've not been able to get it going since. If i give it a push start the engine runs but once i've run out of speed it coughs to a stop. Swapped the carb no change. Got a spare engine to take parts off. Might give the points a clean first though how do i check a spark is getting to the plug on this bike?

A cruiser nodded at me while i was pushing it. I guess he wasn't in a mood to help

Edited June 12, 2010 by Lumor_uk

[eastanglianbiker]

take the spark plug ut of the engine relace into the cap and rest thread part of plug on engine...........turn engine over and see if it sparks

no spark try new plug

[Guest]

have you plenty of fuel..

is this a recent problem or from before you swapped the carb?

[Lumor_uk]

Before I swapped the carb, plenty of fuel, plenty in the carb too when I took the other one off. Going out in a minute will let you know about the spark.

[mealexme]

kill switch?

sorry, but i have read a lot about people recently who have tried to start with the kill switch on. you know who you are!

[Lumor_uk]

It's 25 yrs old...even my CBT instructor was surprised when I said "er mine doesn't have one", he said well it should have.

Anyway I went and tried to start it, it ran for 5 secs then died. I left it for 2hrs then came back and it started again but for 3 secs.

I've checked the exhaust and inlet ports, they aren't stuck I've checked the gap that's fine.

But here's the thing I took off the cover to the stater and loads of oil/water mix came out... it was inside the seal and it's all inside the breaker points. I'm going to take the inline filter out see if that helps as it starting makes me think it's a fuel problem. The oil leak isn't bad enough to take the whole engine apart and there isn't any oil on the floor when I leave it to stand. I think it was blocked with the mayonnaise.

http://farm5.static.flickr.com/4063/4685213801_1e1234fc6f.jpg

I can't get the cover off I've got the right tool but the wrong size, as the tool is for my push bike.

http://farm5.static.flickr.com/4024/4685847394_772c517082.jpg

[eastanglianbiker]

if you are getting oil/fuel mix in that casing there is good chance the crankshaft seal has gone the only way to replace is engine strip down to replace seal as it is fitted from inside engine case rather than dressed in from the outside

[Lumor_uk]

You sure fuel will mix with that? Can you confirm you meant fuel will have to look at the diagram. Got my mod 1 next week its not looking good

[eastanglianbiker]

yep meant fuel .......on a 2 stroke bike the petrol/oil mixture is drawn into the combustion chamber where it goes down around the crankshaft and then in piston chamber to be ignited it is fed round the crank under pressure and if the seal is worn it will escape there hence wont run as the compession is lost

[Lumor_uk]

This is a 4 stroke ?

Picking up a fly wheel puller tomorrow for £10 just down the road.

[eastanglianbiker]

that will teach me to check first.......lol......all that for nothing you need to check points and condensor you can see if there is a spark but looking through gap in rotor if it is points ign you will see them you can use small screwdriver to open them with ign and see if there is a spark as you do it........if not new points and condensor would be first to replace on my list

[Lumor_uk]

there is a spark at the plug, but there is gunk inside the fly wheel. I can't look inside the fly wheel and kick start do I need to get the wife involved?

The hayne's manual says fouled points will stop the engine from starting

[eastanglianbiker]

turn the engine over by hand on the rotor with plug out but if plug is sprking then the points could need the gap setting

[Lumor_uk]

Won't electrocute myself?

[eastanglianbiker]

no fear of that it should just spark buut if you are getting the rotor off you mightas wel change the points and condensor while in there just make sure you set the gap right when putting back together

[Lumor_uk]

Okay cheers

[NearOn]

If all else fails, hire a 125 for the MOD1, at least then you will know wont have a bike with problems.

[Lumor_uk]

The oil seal is attached to the stator so I don't need to strip the engine

This is my spare CG125 engine, can't get the last screw off my bike someone's mashed it up

http://farm5.static.flickr.com/4072/4688085252_3f34918960_b.jpg

[Guest]

The oil seal is attached to the stator so I don't need to strip the engine

This is my spare CG125 engine, can't get the last screw off my bike someone's mashed it up

 

DRILL

drill into the head, the head will come off, then get mole grips on the bolt, and replace with one off your spare engine

[Lumor_uk]

Okay I got the bolt off cleaned it all up replaced the seal, then put it all back together and it was running fine, then I realised I had missed I spring out. Took it apart, put it all back together again and it started 2nd go but was running rough put it in first and it coughed to a stop, won't start again now

I'm guessing I need to set the gap and timing or something as I lightly sanded the contact breaker as their was dimples on the surface.

[eastanglianbiker]

yes you should set the gap and follow directions in manual to make sure ignition timing is right so that it sparks where it should

[Lumor_uk]

Okay found the problem, in my annoyed state after forgetting to put the spring in I hadn't tightened the fly wheel on enough and it sheered a metal erm part that holds the flywheel onto the spindle. I've made a new one sort of out of an allen key for now. Going to post a new thread asking if anyone knows where I can get it from but here it is. I made it even smaller than that but now the bike is running fine

http://farm5.static.flickr.com/4035/4691789952_78584e65f3_b.jpg

[Lumor_uk]

Okay its not fixed. When its idling it runs sweet as anything. But as soon as i try moving off it coughs and coughs but doesn't stall. Is this just the timing? Seems strange it does it only under load. When i read the manual it doesn't state when to take the points gap measurement is it at F or T. I know from checking it that it starts opening just after F and is fully open at T.

[eastanglianbiker]

sounds like the timing is out the points should start opening at the f on the rotor that is when the spark is created take the plug out and place it in the cap rest on side of engine you will hear it spark if it is sparking after the f mark then palte needs moving slightly untill it sparks at the f mark

[Lumor_uk]

Due to my DIY make shift Wooddruff key the flywheel wasn't on properly, I then worked out how to do the timing it's now spot on and running super