Hard to start

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YAMLAM
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Toddy wrote: Mon Apr 11, 2022 7:52 pm Are the reeds ok ? Squeaking not head gasket is it ?
Definitely the reeds squeeking,if you open the throttle it louder.
Will take reeds out at weekend to check.
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GeorgeS
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A backfire sounds electrical.

Note also a backfire can break a reed petal and then it will be near impossible to start.

You might be dealing with more than 1 problem.

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YAMLAM
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Reed`s are ok,
stripped it right down ,had a slight leak from drive side oil seal plate,( althou no leak when engine was on bench with bearing filled with oil ) replaced that and new seal, rebuilt it back up again, had air leak on barrel stud , cured that ,re timed and strobed it at 17 deg.
started second kick , rev`s out fine.
tried to start it next day , nothing, doesn't even fire, checked plug, good spark, plug slightly wet after 8 kicks.
the only thing i didn`t check was ring gap on assembly, but being a brand new kit ,i never gave it a thought.
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Toddy
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Have you got a known good stator you could fit and try ?
As my Dad used to say "Each to their own lad"
gaz_powell
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I had this and it turned out to be stator, it had what appeared a good spark outside the bike, all readings were good. Put a clean plug in and it would sometimes fire, once running revving clean on the stand... Turn it off and wouldnt start.

I pulled a stator from a runner and bingo.

Put new pick up and coil and rewired the dud and hey presto.... Still running fine.
It had a lay up of over 12months as well. When i came to restart I took plug out, cleaned it, same old e5 petrol, bit of brake cleaner into carb and a few kicks.... Alive!!
YAMLAM
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Thanks for reply`s and giving advice, gonna try a known stator, in fact the one i took out when i replace everything with new BGM items, it was running ok with that.
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YAMLAM
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today i put his old stator on that was running fine before , wouldn`t start.checked pick up height, in line , put another CDI on, still wouldn`t start, changed HT lead , nowt, changed Plug cap , still same The green wire from Ignition switch was removed whilst i tried all this.
Im sure now it`s not electrical.
I put it in second gear , opened throttle wide open , pushed it back and forth a couple of crank rotations. kicked up first time . ive now put a 80 pilot jet in , yes i know every lambretta / vespa usually runs on a 70 but im running out of ideas. will try it again tomorrow.
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YAMLAM
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fired second kick with the larger choke jet, then started and ran third kick. now to try it 24 hours apart, but im now a bit more hopeful thaty im on the right track.
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YAMLAM
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wouldn't start 24 hours later.I then put in a 75 choke jet as the plug looked `too wet`, started second kick, came back two hours later started first kick, tried it next day, nothing.
I have now taken the engine out and lent him my TS1 engine whilst i take his apart again to check everything again
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GeorgeS
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A frustrating but also fascinating problem. Please do let us know if you find anything when you get inside it.
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