Won't run after new top end
20 May 2019 15:45 20 May 2019 17:16 by Rick C..
Won't run after new top end #12
21 May 2019 10:15
Won't run after new top end #13
RT325, I need to thank you on this post also, you are a genius. Folks my problem was the key sheared off on the fly wheel shaft. I haven't felt this good since the hogs ate my baby brother!
The following user(s) Liked this Post Blackhat250, RT325
21 May 2019 17:47
Won't run after new top end #14
That's good. I get lucky sometimes. Just be sure is done up tight & held solid while tightening for a good feel of the socket etc. Love ya last line haha, i'll be laughing all day.
21 May 2019 23:31
Won't run after new top end #15
are all these key failures age? crappy keys? I think its under torque of the nut! I didn't believe the Claymer book when it said 29ftlbs for a 12mm fine thread, asked here and came to the conclusion if you use recomended torque values (in rear of most factory manuals) its too low! I finally found a flywheel torque in 74 manual 7.0-7.5 Kpm, which I used. RT said he uses 50ftlbs, with no failures. Is this the possible problem?
22 May 2019 01:05
Won't run after new top end #16
Umm, if RT is me i'm not sure where i said 50ftlbs as don't use a torque wrench but that'd be about right as i just swing on them with 1/2 inch socket & long handle plus of course the solid holding tool against the footrest. They only let go in the first place due to under tightening. I know i've said it before but i had a TT250 which has a heavy flywheel & ran it without the key for a while experimenting with advancing ignition a bit more than std. Same with my totaly mix n match of parts on my IT200, no key & ran for years until i sold it. Good taper & done up tight, should never let go. Actualy all my 360's have stuffed cranks & flywheel tapers from having let go over the years before i ended up with them but despite they're condition they've never let go on me--yet lol. Hell my YZ490 came from Ebay California to NZ with the key broken & first kick out of the crate broke a tooth off the kick idler gear plus bent a tooth on the kick gear itself, back of the clutch little gear survived. Damn near broke my leg when it kicked back. If you think Yamy 360's kick back then you want to try a 490 with the same problem--well no you don't!!.
22 May 2019 22:10
Won't run after new top end #17
My bad RT325, U posted when I asked Torque values "I grossley overtorque", LOL, another answer said 50psi, prostrate, memory, what goes next? LOL . If you liked your TT advanced, I could look for some Mercedes offset cam keys used to dial in cams, I have a bunch of different degrees of change keys around
23 May 2019 02:38
Won't run after new top end #18
My memories stuffed & by the time i've typed an essay of an answer i've forgotten the question lol. Stepped key's yes my TT250 is long gone thanks. Was just another free bike no-one could get running properly. Sounded grossly retarded but turned out to be the inlet lobe on the cam was almost totally round--must've taken years to get like that. Another cam & inlet rocker & she was a rocket. But i experimented with timing initially as they had a habit on that model of shooting the advance stuff in the box to bits & stay on full retard, glowing header pipe & good for a carbon burn out lol but barely drag itself along. Still experimented with timing as well & filed the key to half width & advanced it then did it up tight & worked great. Did try no key & advance it that much but too much. Had it like that for a while & never slipped but was a perfect crank taper & flywheel,
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