gotta give it throttle

2 replies to this topic
  • adz_244

Posted February 17, 2007 - 01:10 AM


following on from my other thread about the 1999 400 i brought recently,i took the bike out yesterday and it would only start when giving it throttle, i also have the common bog where you crack the throttle and it tries to die but i think the taffy mod should cure that,any ideas on the starting front does it point to anything as from what ive read in the searches you should not touch the throttle when starting:excuseme:

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  • grayracer513

Posted February 17, 2007 - 08:54 AM


At low engine speeds, like cranking, what you're doing when you open the throttle is increasing the amount of air in the air fuel mix. Since the carb depends on air flowing through it at high velocities to raise fuel from the float bowl, and since at starting speeds this doesn't happen, you're getting mostly air.

That usually means that the engine is otherwise richer that it should be, and needs the extra air to get back to the right balance. Could be a high float level, or too rich a pilot circuit (jet size or screw setting).

Then, too, if it starts reliably and runs OK, it might be just the bike's "personality".

  • adz_244

Posted February 17, 2007 - 08:57 AM


problem all sorted now the airfilter is on properly,it starts first kick again

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