OzVMX Forum

Clubroom => Tech Talk => Topic started by: pancho on April 21, 2015, 02:18:13 pm

Title: Kick start leg breakers.
Post by: pancho on April 21, 2015, 02:18:13 pm

 Question for theory thinkers. What makes some two strokes vicious on kick-backs, e.g. pre read valve RT1, compared to later model RT series?
 I have my own theory for part of the cause, what do the 'boffins' say?
pancho.

Title: Re: Kick start leg breakers.
Post by: Tim754 on April 21, 2015, 05:07:25 pm

Pancho having owned both pre and reed valve models RT360's.... both types were/are monstrous kick back devils!!!! Later DT360/DT400 model electronic ignition (which bolts on to early engines) was a vast improvement.
Also the early models were neat at starting and running     backwards    :o   

Points ignition with 2 degrees before top dead centre firing and owners not very careful,  precise tuning ,  may answer some of your question  ;) 

Strangely I love the old Yammie 360"s :)

Title: Re: Kick start leg breakers.
Post by: Iain Cameron on April 21, 2015, 07:28:52 pm

Once I learnt that the DT400 cdi fitted have never had a problem since . Mind you a RT1m with a gyt high comp head makes a British 500 single look easy . Iain

Title: Re: Kick start leg breakers.
Post by: Rossvickicampbell on April 21, 2015, 07:33:11 pm

agree with Iain - the timing was out on my YZ 360 - what a bastard of a thing - and broke the kickstarter crank boss  >:(

Title: Re: Kick start leg breakers.
Post by: Hoony on April 21, 2015, 07:39:11 pm

early CR500's (1984 -86) aren't much better, its a real knack to fire them when cold.

Title: Re: Kick start leg breakers.
Post by: pancho on April 21, 2015, 10:58:25 pm

 I believe PART of the problem is weak spark=poor flame travel.  Evidence= it's a lot worse with the engine cold. Plus When I put total loss battery coil ignition on, getting over 10mm spark at kickover a big improvement.  (But I still took the kicker off)
 
 pancho.