Setting up my Biturbo and Amal 15mm

I have an 83' Puch Dart. Just installed a 70cc kit on it with biturbo and 15MM Amal. I'm having trouble getting the ped running. It has spark and fuel. It even kicks a bit after letting it sit between starting attempts, but doesn't run. If i pull the plug, it's wet.

Any suggestions for baseline settings for the mixture adjustment, and/or any other ideas about getting this beast started?

thanks in advance.

tv kupa

Re: Setting up my Biturbo and Amal 15mm

an additional note- I changed the plug this afternoon, and got it to catch a bit, sputter and run for a few seconds, then it stalled. I can repeat this, but still no luck with consistent running. I bet there's an expert here that knows what the best set-up is... :-)

tv kupa

Re: Setting up my Biturbo and Amal 15mm

I'm no expert but that definetly soudns like flooding. Im not sure abotu the amal carb but try a smaller jet or take out the lean out the mixture some.

Re: Setting up my Biturbo and Amal 15mm

do you have compression? turn the flywheel by hand. on the intake/compression stroke you should feel a lot of resistance, on the power/crankcase-compression stroke you should feel not as much resistance and hear a pop sound as the intake port opens. if you dont have good compression, you might not have gotten the crankcase/cylinder gasket or the head gasket sealed good..

Re: Setting up my Biturbo and Amal 15mm

thanks for the suggestions,

compression is very strong- it has fouled two new cotter pins on the crankarm from my ambitious jump starting technique.

the new plug seemed to help a good bit. got it running consistently this afternoon. i fiddelled with the mixture screw and tried combinations of choking and not, with holding the throttle open and flicking as it caught. The best combo seemed to be flicking the throttle slightly with the choke open. problem is, even with the idle setting as low as it can be set, the carb draws too much fuel revving the engine too fast, and the idle mixture has little to no effect.

I'll check to see if the needle has a lower setting in the throttle slide, otherwise, perhaps a smaller jet is in order. I hoped that the kit would have been balanced for jet size, throat diameter, pipe and 70 cc jug, piston and head.

this is going to be a bit more tuning than i hoped for, for a little two stroke novelty item (already have too many motor toys- moped/scooters- das puch, NQ50 spree, Yamaha Razz, a motorcycle- Honda cbr1100xx, and four wheeled toys- porsche turbo, and toyota fj40)

next weekend- install the new brake pads and larger front cog and try it on the road. yikes is it loud, annoyingly so, to this middleaged set of ears... ;-)

tv kupa

« Go to Topic — end of thread

Want to post in this forum? We'd love to have you join the discussion, but first:

Login or Create Account