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Discussion Starter #1
OK..I thought I had this licked. Had some electrical issues at Jennings and thought after rewiring the bike she should scream. Uh Uh, ain't happening. 105 secondary mains. New diaphrams. New points. Timing set and checked with a light. Engine breaks up around 9000rpms runs rough and thats as far as she goes. I need this thing running before Barber next week. Good gosh..this is embarassing but I am at wits end.
My plugs tend to look sooty and the bike has exhibited these same symptoms with jets from 105 to 125. I rebuilt the engine and it has new pistons and rings, fresh bore and valve job with copper head and base gaskets, stock valve springs, K0 cam and rockers. Points ignition with stock coils and NGK wires and NGK iridium plugs. It starts very easily and runs crisp off the bottom, pulls hard in the mid-range then gets a lil' rough on top and stops pulling...this can occur any where from 7000-9000. HELP!!!
 

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Try smaller main jets. If you are running the stock CV carbs then you may need smaller than stock mains. Are you running velocity stacks? I use the stock rubber velocity stacks from the original air filters and they will flow a lot better.
If the plugs are sooty and going bigger on the mains doesn't help, then try leaner.

Ken
 

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Discussion Starter #6
I have velocity stacks and am at 105 secondary mains now. I don't have anything smaller.
I am stuck with my valve springs for now and the bike has turned 10500 before in a quick blast up the street here. At that point I felt it was fixed but then had the same problems at the tack. No top end. Sigh.
 

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Discussion Starter #8
Yes, the old stock coils. I will see if I can find someone with a set to try.
Thanks.
 

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Discussion Starter #9
I'm in Rome, Ga if anyone has some spares they are willing to let me try.
Brad Padgett
 

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yep. coils will do that. the warmer they get the worse it will be too.


jc
 

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it could be point float. i was having the same trouble at mid-ohio. if you are going to use the stock points plate, i've been told by gary swan to use 1 and a half springs on each of the points to prevent float, i haven't tested this under track conditions yet tho.
 

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Discussion Starter #13
Mine does tend to get worse as it warms up. So Rosko u are running the advance welded at full advance? How hard does it make starting? Mine is bump start only. I don't understand why points float would be a problem but I know Gary knows more than me. Stock bikes turned more than mine is.
 

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Discussion Starter #14
Rosko...what kind of auto coil? From what? How are they wired in and where did you mount them? Pictures? I know I ask a lot of questions but heyI am new at this and would like to have this thing running right for me second race.
 

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my pvl is locked at full advance. so was my dyna. dont believe the hype about starting and advanced igs on those bikes. ive seen them lock wired too. i dont see why you couldnt take it out either.

if it gets worse as it warms, its defnitely a coil.

look for wax seeping from them.

jc
 

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Discussion Starter #16
I just mounted two coils off a Yamaha TX500. When I get 'em wired in I will let you guys know how it goes.
 

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I seem to recall that Yamaha used a grey and an orange wire to their coils and orange was the hot and grey was the trigger. But I am not sure and I am not at home to check one of my Yamahas. If you are running V- stacks, then it could be ignition. You can just safety wire your advancer to full advance to check it out. I ran a race bike like that for years. I did a temporary repair at the track when I broke an advancer return spring and left it since it worked.

Ken
P.S. Could still be jetting
 

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Discussion Starter #19
Thanks guys got the coils wired in and fired her up. No improvement so I just threw caution to the wind and took the advance springs off and just let the weights freewheel and she hit 10k before she gave out. I am picking up another advance unit from a bud tomorrow. Thanks for all the great input guys!
 

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better than the wera board eh? see you still have no answers there!

cool!

jc
 
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