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Scooters - 50cc => Agility 50 => Topic started by: Scuzz on December 24, 2011, 06:16:38 PM

Title: 80cc big bore
Post by: Scuzz on December 24, 2011, 06:16:38 PM
OK, I've installed an 80cc big bore kit in my 2006 agility. The bike would start but cut out, but now it wont start at all. I have installed a #94 jet in the carb etc. Would I need a larger pilot jet? Could it be the exhaust? Any help would be appreciated.
Title: Re: 80cc big bore
Post by: Scuzz on December 24, 2011, 06:33:35 PM
I've also checked the spark plug
Title: Re: 80cc big bore
Post by: blue on December 24, 2011, 09:27:59 PM
the best thing would of been to leave it as a 50. I would of loved to do that too but everyone I know that has. Had problems later. Happy I did now. I have a agilty also its a 07 and running good yet. good luck. sorry to sound rude but just saying it as I see it.
Title: Re: 80cc big bore
Post by: Scuzz on December 24, 2011, 09:48:03 PM
Maybe you're right but it doesn't help my situation, thanks anyway.
Title: Re: 80cc big bore
Post by: sidthesloth on December 24, 2011, 10:10:27 PM
Do you have spark? Are the valve clearances correct? Is the valve timing correct?
Title: Re: 80cc big bore
Post by: sidthesloth on December 24, 2011, 10:16:59 PM
Blue, I have two sym vs scooters, a 125 and a 150, the only difference is the cylinder/piston. the only difference in the tramsmissions is the roller weights, 10 v 14 grams and the drive boss is 1mm shorter on the 150.
Title: Re: 80cc big bore
Post by: Scuzz on December 24, 2011, 10:17:59 PM
OK I haven't checked the valve clearances, but there is a spark and the timings are correct. Cheers
Title: Re: 80cc big bore
Post by: sidthesloth on December 24, 2011, 10:21:21 PM
If you haven't done so already, it won't hurt to recheck the valve timing, for peace of mgpgnd if nothing else. Is fuel getting through to carb and cylinder ok?
Title: Re: 80cc big bore
Post by: Scuzz on December 24, 2011, 10:25:10 PM
Yeah I think the fuel is getting through OK
Title: Re: 80cc big bore
Post by: sidthesloth on December 24, 2011, 10:36:39 PM
Is your spark plug wet with fuel?
Title: Re: 80cc big bore
Post by: Scuzz on December 24, 2011, 10:42:50 PM
Yup
Title: Re: 80cc big bore
Post by: sidthesloth on December 24, 2011, 10:53:06 PM
How is your compression, if that is ok then it is back to valve adjustment/timing.
Title: Re: 80cc big bore
Post by: Scuzz on December 24, 2011, 10:58:52 PM
I haven't got the right device to check compression. Are you sure it's nothing to do with the jets?
Title: Re: 80cc big bore
Post by: sidthesloth on December 24, 2011, 11:07:31 PM
It should run if you have fuel, ignition and compression. If not enough fuel it would run rough, but should still run.
Title: Re: 80cc big bore
Post by: REDKYMCO on December 24, 2011, 11:20:16 PM
I have never really looked into the idea of fitting a big bore kit but i would have thought as you are fitting a bigger cylinder then you would also need a larger carburetor to allow for the extra air the scoot needs to breath in and larger exhaust for the higher volume of output, otherwise i would have thought you would be choking the engine......
Title: Re: 80cc big bore
Post by: sidthesloth on December 24, 2011, 11:33:15 PM
Correct, but it should still run.
Title: Re: 80cc big bore
Post by: juice on December 25, 2011, 12:06:37 AM
Does anyone have or know of a successful 80cc 4 stroke conversion ?
Title: Re: 80cc big bore
Post by: blue on December 25, 2011, 01:02:42 AM
Blue, I have two sym vs scooters, a 125 and a 150, the only difference is the cylinder/piston. the only difference in the tramsmissions is the roller weights, 10 v 14 grams and the drive boss is 1mm shorter on the 150.
some scoots are easy to mod and some are not most the 4 strokes I have seen are 50s being made to go faster by bring theam up to a 70 kit or 80 they well coast ya later by doing so.now going from 125 to 150 may be dif.
Title: Re: 80cc big bore
Post by: woodcutter on December 25, 2011, 10:33:41 AM
scuzz, did you installed piston rings corectly?
Title: Re: 80cc big bore
Post by: Hoolander2 on December 25, 2011, 04:42:11 PM
So it did start at least once but cut out.  Spark plug is wet.  Try running without the air filter for just a minute.  That might tell you if your jetting needs to go up or down.