athena big bore

5 replies to this topic
  • let_me_color_u

Posted September 26, 2007 - 02:02 PM


ok first and foremost, you guys have been alot of help and i want to say thanks so much, i got my bike back together today and to give a little history i tore my knee up in march 2007 the acl, mcl, the meniscus and have some cartlidge floating around in there, i wear a don joy brace on my knee every day, i being the impataint man that i am did not adjust the valves when i put the bike back together, i insatalled the athena 480 kit i tryd kicking it over today and got one good kick before my knee really went south i tryed kicking it several more times but dont think i had enuff umph maybe my valves need adjusting or i just need to roll start it i can feel alot more compression than before, i bared it over several times during reassembly and everything felt good, i didnt check the valves because i dont have any shimms if i needed and wanted to fire the bike up, my timeing marks all look good but i have a question my crankshaft has 3 marks fairly close together when i took it down it was lined up to the 3rd mark going counter clock wise, why is there 3? and do you guys think its my valves now, also how many kicks does it usaly take to start after a new top end like this? i did not rejet my carb, could that be a issue? thanks thumper talk you guys kick some ( well,,you know)

  • grayracer513

Posted September 26, 2007 - 02:52 PM


On the timing marks, the first two are for strobe checking the ignition timing, and the third one is TDC. To clarify, the one at 12:00 is TDC, and the two at 11:57 and 11:58 are ignition timing marks.

If the bike sat a while, the pilot jet could be varnished over, or the float could even be stuck shut. If the valves were correctly set to start with, they should be fine now, unless you mixed the lifters up or changed cams.

  • let_me_color_u

Posted September 26, 2007 - 03:39 PM


being the smart guy that i am i turned over the head and 2 of the lifters fell out, i figurgerd i had a 50/50 chance of putting them back right, the 2 shims were different, if i check valve clearance now would be a good idea huh?

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  • grayracer513

Posted September 26, 2007 - 03:46 PM


Theoretically, the lifters are so close to the same that it won't matter. Still a good idea to check, especially if the shims were to get back on the wrong valve.

My experience has always been that when there are two possibilities, I have a 5% chance of guessing the right one.

  • let_me_color_u

Posted September 26, 2007 - 04:13 PM


i will check valve clearance tomorrow and i did have the carb upside down during repairs, is that gonna matter?

  • grayracer513

Posted September 26, 2007 - 04:32 PM


Not unless the float stuck shut because of it. Open the float bowl drain with the fuel turned on. If nothing runs out, you have your culprit.

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