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Stupid Is As Stupid Does.

Featured Replies

  • Author

Starts, ticks over, pulls well but doesn't run well at full throttle. If it's dry tomorrow I'll go out with a screwdriver and have a tinker with the air screw.

Please excuse a fellow whose having some health problems but I am very old but have run Bulls for MANY Years, I

will share my knowledge to try to help.

(1) Never trust the new CONDENSER you can buy!! Add an automotive condenser beneath the tank!!!

(2) The carb looks Mikuni 26mm from locally, 100/120 pilot jets, 100/130 main jets.

(3) Timing, 2.8mm or pluss a little BTDC. firing.

(4) No idle on the throttle, start engine choke on , should start, let it warm up before trying to ask questions about leanness,

Please trust you have the BEST ENGINES ever !!!!

Good Luck

Larry

I think 20 - 30 pilot is the go for a Mikuni and 130 main for starters

PS they really are simple motors that are built proof as lbhbul said

Edited by sherpa325

  • Author

The Carb bought new from Bultaco uk (In Motion) and jetted for this bike. I'm presuming it just needs a little air screw adjustment. Not today mind. Absolutely persisting down.

Actually I don´t think air screw setting will affect full throttle running. I also belive that todays brakers and capacitors  don´t do their job well. It is trials season in UK. Get an electronic ignition. You won´t regret it.

Please excuse the wrong pilot jet size I printed out , our sort of stuff would be for the 26mm Mikuni usually 

 

35/ 50 pilot size.

 

Thanks.

 

Larry

  • 2 weeks later...
  • Author

Took the bike over to an engineer friend for an afternoon of drinking tea and fettling. Checked the carb and everything is as it should be.

Ordered an electronic ignition kit from Bultaco UK and it will arrive tomorrow. Watch this space......................

  • Author

I'd been thinking of fitting electronic ignition for a while but thought maybe I should wait until after xmassmuss. Then I remembered I never buy anyone anything anyway so it's fitted and has runs like a dream so big thanks to all for advice and support.

Ho Ho Ho indeed ;)

  • Author

My engineer friend have a quick test.

 

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